Follow-up: I actually had never looked at the Rev A C64 video output circuit on the schematics before. It turns out the RF modulator is not part of the Chrome/Luma processing at all on this revision. (It's the only one that's like this.) See the top right part of this schematic: www.zimmers.net/anonftp/pub/cbm/schematics/computers/c64/326106-2of2.gif That means this mod surely worked OK at some point. I think the issue I was seeing with the luma signal being super low was due to bad soldering or broken traces because the rework done was bad. When I restored the board back to the original 5-pin connector, I fixed a few traces with bodge wires near the video connector and now everything is back to original condition. (I also restored R10 to be 120 ohm as specified on the schematic. It was 300 ohms on this machine.) Ideally, a RF modulator replacement could be created to output S-Video and Audio but this would require a could bodge wires running to FB14 and FB15 near the VIC-II. Also ideally the entire original video output circuit should be disconnected and a new composite feed be fed into the DIN-5 from the new RF modulator board. See Mark's video here: th-cam.com/video/LB2gtMQyjqQ/w-d-xo.html
Ever checked out the BitScope units? I've been eyeing one up because the software looks really interesting. Besides normal o-scope stuff, it can also do data logging. Thanks again for another great video. I need to go dig the C64 out of my parents basement to see what Rev it is. :)
Adrian, I have the same 326298 Rev A board, but with the original heat sink. The back has the same red and black bodge wires installed the same way as yours, and an 8 pin video connector. I got this board back in the late 80’s when I worked for a computer store in Connecticut repairing Commodore and Atari PCs. I also got some spare parts, 4 boards in various rework condition, a case with keyboard and a spare broken keyboard. I’ve been repairing my own personal C64 with a 250407 which is still stuck on black screen, fighting me every step of the way. I repaired 2 of my extra boards, both 250425 and installed one in a case, the other I socketed out as a test bed trying to repair my original C64 board. I socketed every chip in the 250407 board and every chip from it passes diagnostic test in both of my 250425 boards. Still stumped.
Hey! This exact scope helps me make money almost every day. I repair power invertors and it is essential for getting fast reliable repairs out. Regards from far Ukraine
I understand that because 80 dollar is a lot of money in your country. I repair too for a living but I am happy I do not have to use this thing. But it is better a nothing. I would stay away from inverters. I use a HV diff probe for working on inverters.
I don't know what YT video creator is worse for my gear acquisition syndrome - you or Mat from Techmoan! Great content and I look forward to seeing you use this scope on more projects.
Hi Adrian you did a great interview on the The Retro Hour (Retro Gaming Podcast) this week. Thank you for sharing your early years with us and how you became interested in electronics. Cheers Tim
Thank you so much for this review! When I first time saw it (a year ago) I immediately decided that I need this oscilloscope. Now, when I bought it and it finally arrived, I'm watching you review again with a pleasure of being able to try everything and use it. Thanks again for such a great review!
I bought this as my first ever scope after seeing lots of reviews, and I'm happy with it for the very occasional times I need a scope. Yeah the software is kind of infuriating although the github version fixes some of those annoyances. But the UI as a whole could be a lot better, making use of the large screen of a laptop to lay out more immediate controls instead of requiring menu diving. But as you say, the scope itself seems very capable, fast and accurate, and that's surely the most important thing.
I do enjoy seeing all of these cheap scopes as options, especially for beginners. 11 year-old me would have adored one of these on my electronics bench in the late 1980s! I personally ended up buying a standalone Siglent SDS1104X-U because I needed something that could do a little more and was a little bit more reliable, as well as four channel. I kind of wish I had sprung for the -E Model as it has a port to add a digital logic analyzer to it, but I didn't really have the money at the time.
I have the SDS1104X-E. I wouldn't be too unhappy about not getting the E model. The logic analyzer is rather pricey (almost as much as the scope) and, from what I read, not all that great (missing trigger off digital options, for example). Makes sense - the digital module isn't like other scopes where all the logic is in the scope and the pod is just buffering/signal conditioning. Have to step up to the SDS2104X-Plus to get a more digital logic analyzer setup. Its definitely a much nicer scope, but quite a bit more expensive. I'm happy with my SDS1104X-E - it's alot of scope for the price.
i have the non-isolated version since about 5 or 6 years ago (haven't used it much, though); the software is java and, at least when I got it, it came with source code (possibly by mistake), at the time some people were trying to make it work on linux, IIRC, it's great that now there's opensource software for it!
Isolation is a really big plus. On the other end of the spectrum are oscilloscopes that connect ground of the DUT with the ground of your expensive laptop/desktop computer. Why even bother with USB oscilloscopes...
I have the 100mhz model with built in awg. It's such a handy piece of kit to have in my bag as a service engineer. I highly suggest upgrading the leads. I use Probemasters (DMM and scope) with mine.
@@graealex in the US laptops are cheap. I can get a used one for $20 or free. If you're hooking USB scopes to your expensive computer that's really your fault.
If you play a little with the software and learn the "shortcuts" this thing it's a beast! It's really fast and the open source Software it's like a candy! PS. Great work as always!
The 57 dollar scope you showed has been a nice addition to my bench. I grab it all the time now for quick signal checks. I have several other scopes, but it is super convenient.
Pro tip: Oscilloscope probes with 1x/10x usually only have their full rated bandwidth at 10x setting. Working on 5v stuff you can use 10x attenuation with not much added noise and it may sharpen those waveforms up a bit.
The open source software interface for this scope you linked in the description is definitely better than Owon's. Has a little more functionality and control. Will allow you to use the scope on Linux too.
The scope reads UOMO when it was upside down on camera - "Man" in Italian LOL. Nice video, I like how you manage to mix the new equipment with an actual repair! The scope looks very good to me - the UI is improvable but I guess you can get used to it. What really matters is that for only $80 you get what seems to be a very capable hardware!
Seeing you happy and laughing is the best for us all. I think you have a great humour for the group cinema watching, sadly you don't do live streaming of such.
Adrian, I know the interface frustrates you, maybe because it isn’t more standardized but from working in industry (Westinghouse and Kodak), every time we purchased a new sophisticated piece of test equipment, they all had complex unusual interfaces and a long learning curve. I think this little oscope is very capable, you just have to get over the hump in the learning curve! Great review! I think you had a predecessor like yourself who modded up that gen 1 c64! Another thought, I’ve never used a SW based scope like this, so learning the interface would seem “normal” to me!
Yeah it's kind-of annoying. People think everything should work the way they know, but there is no rule that says every same category software HAS work the same. You can't even jump from EDAs without learning the others first, unless you want to be super inefficient, ie, slow. I watched a 1hr KiCAD vid and knew more than EEVblog fumbling around for 4hrs saying KiCAD was rubbish, when he didn't even know it. Basically, if it's a different program, it's going to have a different way to do things, ie, RTFM beforehand - lol -. I would laugh if this SW could do everything he wanted using shortcut keys, just because he didn't look up help - lol -.
@@SidneyCritic I agree that you for sure should spend time learning new test gear, however there is no excuse for not making the software easier by leaving user inputs unused. For example with the mouse pointer above the waveform the mouse wheel should do SOMETHING, having it do NOTHING is just lazy programming. The same goes for the right and left mouse buttons when hovering over different things. I have the VDS6104 and it's great, in fact they have already fixed all the things mentioned in there, you can scroll on the waveform, right click and drag the waveform, right click the channel markers to reset etc etc.
@@mrfrenzy. Conventual is better, because if you don't use unconventual for a long time you forget how to use it, but there could be reasons why it isn't conventual, eg, they just don't know. Just looking at the manual there are shortcut keys. ADB should've read the manual - lol -.
@@mrfrenzy. It seems there are quite some keyboard shortcuts though, but this implies they want you to use both the mouse, keyboard and lead with 3 hands.... idk how that works?
Love coincidences like this. I've been using this exact model of Owon for the last two days and it's my first o-scope of any kind so I kinda jumped when I saw this video in my feed. You wouldn't believe how embarrassingly long it took me to realise the hook portion of the probe just pulled off and I struggled with hours using it with the hook on
I could remember this Mods. I live in Germany and that was described in magazines. It was an series starting low level things and gaining the higher thinking. The voltage mod I have made together with a small peach of copper that I had. And the mod with the Luna mod I remember. They had a special monitor in the lab and did not thought about that a normal monitor is not so sensitive. Two weeks later they explain the mistake.
As the mods began to be revealed that is exactly what I thought, "These mods were done by an enthusiast at home with limited skills and equipment" and a magazine of the day would be the exact place the information came from.
I was told once that the hardest software to learn is the second one. (in reference to CAD in my case) once you get used to something you get frustrated when it's not where you expect.
Well... the problem Adrian's is experiencing is largely that this software doesn't comply with current norms of UI expectations. You'd expect you can just "zoom in" on an element, because that's how most other software is. The current model for any visual element is to treat it like a physical object with the ability to change things right on the object rather than having to go into an obscure menu somewhere. When it doesn't behave like that, people say it's "non-intuitive". In other words, intuition is built upon how you've experienced other software. If suddenly everyone has the little gear icon in a UI and it represents settings, then that becomes intuitive. If a designer expects you to do everything backwards from the way everyone else does it, that's not a great UI design.
@@stevesetherThere is good open source software for VDS1022 so I guess Owon doesn't spend time improving the official software for this old scope. The official VDS6104 software is quite good, zooming, right clicking etc on wave form and channel levels works as expected.
@@mrfrenzy. I couldn't find anything that looked like the UI was fully OSS. From what I can tell the software on Github in Adrians link is largely compiled Java classes pulled from the EXE, combined with firmware pulled from the EXE. Is their some OSS software for this I'm missing, or is the Java UI source available? the only java source in that Guthub repo is a small wrapper for a C library that interfaces the USB.
@@stevesether I don't think using an unmodified scroll wheel to zoom is intuitive. On the other hand, using the scroll wheel over a value is expected to change that value. If the scroll wheel is to zoom in the waveform I would expect you to need modifier keys. Probably one key for horizontal and one for vertical.
I have it and I love it ! For this low price , it's the best choice for beginners . I use with a old PC , a kind of notebook with 10"" screen and it make the job for me ! Very good choice !!!
The keyboard shortcuts for adjusting the horizontal and vertical scales make this scope much easier to use. At 11:31 in the video the “tips” menu in the Owon software has a tab for these. It takes less than 1 minute to learn them. Florentbr’s version is better, and has even more keyboard shortcuts. Newark/Farnell also sell versions under their Multicomp Pro brand. They are usually more expensive, but sometimes are on sale. I picked up the non-isolated version from Newark for $56 US in early January.
I don't know how I ended up here but I did watch through to the end. Oh, it was the oscilloscope. I'm looking to purchase one and really taking my time about it...looking and listening...
At work, when we need to remove epoxy, we use a heat gun which softens it up enough to let us get an Xacto knife or pointed implement under the epoxy and lift it off.
I got a Multicomp Pro MP720016 and it's basically a re-branded Owon VDS1022 (non-isolated) so it uses the same software. It's the first scope I've ever owned and functionally it's a good fit for doing hobby electronics. It has good edge triggering and I also figured out how to capture single trigger events which is very useful.
Hey Adrian, love the videos. An idea for a video that I think a lot of us would love to see, how about a Oscilliscope 101 video. You convinced me that I need one of these in my kit for working on Retro PCs, and when I got it and turned it on I realized that I had no idea how to use it.
This isn't about the content of the video, but every time I watch one of your (very amazing, long time viewer, big time fan, love your stuff) videos when it gets to the intro I expect a skip button to appear because it's so iconic it's logged in my mind as television.
Haha. A software guy here. The GUI environment used for the interface defaults to handling mouse clicks in the "current window," which in this case is the last one where interaction happened. Handling at top level as you wish is certainly possible, but requires fiddly extra effort. I guess they haven't done that. Thanks for a great pointer. Was looking for a usable cheap scope. Guess I'll give this a try.
My Rev A has the same Video modification. The Chroma Luma video works on it, I don't know if there was more to it than just the jack mod and wires which are done in a very similar way on mine. Maybe there is a portion of the mod that wasn't completed on the one you have? It is also a bit of an odd board otherwise. I think someone cared about it at one point, but it had been mistreated in the years before I got it. I may be mistaken, but I believe that board doesn't pass the Composite video through the RF Modulator. Ray Carlsen has a fix for R10 to bring the video level up on that model board, as you mentioned it was light. It is cool seeing another of those boards with the video mod. To bad it doesn't seem to work properly on yours.
Another advantage of an isolated scope is that it allows measurement of differential signals. This would otherwise require 2 probes/channels to measure both single ended signals...
I will need to (partly) disagree with you. Even with an isolated oscilloscope you want the ground probes to be connected to an RF ground, otherwise the shielding becomes a giant antenna. For sensitive signals that could be a problem.
@@eDoc2020 I agree, it really depends on the situation. Had a use cases in mind such as RS48/CAN or voltage transitions over components where the frequencies aren’t that high. As usual in electronics, you need to your wits….
I have this scope and it works on a mac and linux, software and method to get it working is a little more involved. Turns out the software is Java based, and all you have to do(from what I can remember) is install Java for MacOS, run the executable for windows. The only real hard part is getting the USB working which wasn't hard on my 2021 M1 imac, which has a stubborn USB in its own right. Otherwise, once you get the software up n running, the scope is great for basic stuff as shown in the vid. I hope this info is helpful for a fellow mac/linux user. Edit: I had no issues getting zoom to work with mouse on this.
I'm really enjoying your cheap scope reviews, hope it doesn't drive you mad! I liked your almost thumbs up review system too. I survive on my USB 2CH Hantek using the hScope app for my phone, but would like to change up, this could be a nice little upgrade. Cheers!
Thanks for the video and showing off this little bugger, Adrian:) Suggestion: Always use your google-fu with the keywords + "community software" ... as an insider tip. Oh and even better: Do that BEFORE you buy such a soapbox, hehehe:) (Not directed at you. You obviously made a product review. But to the other clueless ones out there, including me:P)
I would like to add some feedback from the perspective of someone who knows nothing about oscilloscopes, but is at the point where considering acquiring such a device to further knowledge and capability. First, I have gained the intuition that this two part solution, the sampling device and computer, is the future for enthusiasts. Only the software holding this evolution back. Second, by reviewing such a device using actual use case and practical example, you provide an oscilloscope fundamentals tutorial with key areas that stuck in my memory model way better than just working principle in theory alone could have done. Thank you, and I hope this feedback is of value when considering the impact of such enthusiast videos as yours on your viewers. Definitely learned a few things today.
Way back when I worked in manufacturing, I used to touch up the circuit boards that came out of wave soldering. We would insert headers and things that couldn't otherwise survive the trip through the wave soldering machine and we also installed ECO wires. When we installed wires, we would use some "super glue" to hold the wires in place and route them neatly, or at least I did the neat routing at the time. Once our wires were installed, we used some De-Sol as it was called to remove the extra flux and we then trimmed up any extra pins and inspected for solder shorts. When I finally became a tech, I was quite proficient at replacing chips due to my touch-up experience and I can proudly say that there was little difference between my chip removal and hand soldering compared to what was done on the manufacturing side. Sadly, this wasn't the case for all the techs and many ruined boards very badly as was the case with field returns. This was a common occurrence when I worked in field service where I received circuit boards and equipment that was already 8 or 10 years old. With those boards, some dating back to the mid to late 1970s, the pads were ripped and wire-wrap wire, or bus wire as we called it, was a common sight on the backs. When I received those boards back from the field, I learned quickly enough to check for that before even powering up the boards because in many cases, it was these poor repairs that were causing the more recent problems due to cold solder joints or intermittent breaks in the copper traces. Those USB scopes are amazing critters compared to the old Tektronix 465B which I was so accustomed to.
Regarding isolation, even with low DC you might have a problem if you want to probe in reference to something other than ground. Not usually something you'd do but sometimes you need to.
Good point. I've found it useful to probe some circuits that have low-side switches in their power circuits and the scope would be bypassing that switch entirely and causing the circuit to always be on. I've also got some isolated TTL UART to USB adapters my company made for our test jigs. Very useful.
Not really a problem when the usb side is isolated. At that point it is the same as a battery scope or even a multimeter. What you can't do is probe two different points with different reference commons.
I am glad you not only show toy scopes (but I am not an Owen fan) The scope is the eye of the electronics repair person, that is why it is my most expensive bit of kit. I use a R&S 300 MHz scope. Beside that an isolated scope meter from siglent, not a bad scope but the UI is bad, triggering is pretty good and rhat is very important . A scope is nice but a lot of uers have no clue how to use it. Fine for checking ripple on power rails but you can do so much more
I put an audio out on something and recorded the oscillation in Audacity (free software). The zoom is amazing. It doesn't work above hearing range, but the perk is to hear it as well.
Most of the ui related problem you had are easy to solve by using the keyboard shortcuts. (Change timebase,v/div,trigger,) And all the triggering are done in hardware. The scope has an FPGA that handles that
I have one of these scopes, and I agree that it is very capable for a reasonable price. It found the problem I was looking for in a 675kB/s RS485 system with no difficulty.
For a lot of apps like that, sometimes you have to hold control/shift when scrolling the mousewheel to select the type of zoom you're after (eg; zoom, scroll, etc)
@@Blitterbug either way, he sold me on getting that as my ideal oscilloscope for any kind of work that I end up doing. Pair that with a $250 HP netbook and you're golden (netbook, not a Chromebook. Runs full fat Windows 10)-- 128 gig eMMC ssd soldered to the main board, 4-8 gigs of RAM, and a dual core i3, little 13-in screen, but it does 1080, I own two of them and they are fantastic little on-the-go machines
One of my favorite things about those HP netbooks is their keyboards, you would think it's some squishy cheap piece of shit, but it's actually really satisfying to type on. Much better than my $3,500 razer blade pro's keyboard for sure.
At 4:41, you say that the AC voltages in a PC are isolated from the AC supply. I'm not a pro, but I didn't think there were any AC lines inside a PC, at least a modern one. At least from the ATX spec and later, all internal power inside a PC is DC, right? Do some older machines have a 12V AC line as well? I just didn't think that AC would be of any use inside modern transistor based processors. But I'd be curious to know if that's untrue!
It's all about what that DC is REFERENCED to. Say you have the "Zero Volt" rail (black ATX wires), and you call that the "DC Reference voltage". Now when you have a +12V wire, that's 12V higher than the reference, +5V which is 5V higher than reference, etc. However if you make the 5V rail your reference, then the 12V rail will measure 7V... that is because both the 5V rail and the 12V rail are referenced to the same "zero volt" rail. They are not isolated from each other, they share a common "ground". In a PC power supply, the "zero volt" rail may or may not be fully isolated from the mains power. The first thing that happens is that the Mains AC gets rectified using 4 diodes, to create a high voltage DC (120V AC >> 170V DC or 220V AC >> 310V DC). So, we have a fairly high DC voltage, which then gets converted to DC by the ATX PSU. The trick comes with the Mains Earth (Ground), which is actually connected to AC Neutral. The ATX PSU will be grounded, and that means that the chassis of the computer will be at AC Neutral. If the motherboard or any other component connects the DC "Ground" to the chassis "Ground", then the ground is now referenced directly to Mains. None of that matters if your scope probe is connected to an equal "ground". However if you connect the negative probe to a point which is higher, then power can flow out that scope wire and back to the mains. It loops around and creates a literal short circuit. For example, let's say you want to check the voltage of a power supply after the bridge rectifier. There is a smoothing capacitor rated 400V DC so you connect your scope lead onto the Negative terminal and... BOOM. That's because the Capacitor "ground" is not really at "zero volts" like the chassis ground or scope ground might be. Sorry, that was not well written, and it's very hard to explain here.... hope that gives you a few hints.
Maybe the infinite persistence setting has a limit to the number of traces it can store. When that counter wraps around, it would overwrite the previous traces stored there. It looked like the major signal got quite bright, and the signals that happened less frequently would disappear after a while.
I the back of my mind I'm thinking about this C64 compared to a Raspberry Pi Pico for a project. Astounding how things have changed in 40 years, while some things still similar or at least recognizable. 😃
27:00 For Christmas of 1982, there were many defective units coming off the production line. They were storing those in tractor trailer trucks in the parking lot; however, some of them were actually shipped as the folks picking up the trailers were either not informed that they were filled with defective units. Or, they were purposely shipped just to get the product under the tree for Christmas Morning with the expectation that customers would return them later for replacement. So, I suspect that this unit was a warranty return to Commodore who might have replaced them with working units and serviced the defective units as time permitted over the following couple of years.
The A to A controller would be because the device is technically a switched mode microcontroller board, and can be configured as a host or a client device. However, it should just use Micro-C for this. USB-C mini would also be an option, but that was phased out with USB 3.0 and was even rare before then. (It's a modified USB Mini connector with an additional pin and a slightly different shaped shield. I actually have an adapter that came with my printer's set of 3 inch adapters for hooking up any and every USB camera in existance.)
If Possible, would you do a video to fix the Luma/Chroma on this Rev A board so that the 8 pin dim works? I have a 5 pin dim that I would like to convert to an 8 pin dim.
This looks like what I need for when I need to show waveforms on my TH-cam channel. It's not going to be as capable as my Tektronix bench 'scope but for a lot of signals it's quite good enough.
Great video as always, hopefully this will get an open source treatment as well, seeing how good/capable the hardware is. Also looking forward to the live stream 😊
A few people already mentioned this open source software does exist! So I'll need to do another repair with this software: github.com/florentbr/OWON-VDS1022
@@adriansdigitalbasement The Github version adds mouse scroll wheel zoom on the time/div. Lastly, there is android application called HScope that supports the VDS1022 with an on the go cable. So a phone or tablet that supports OTG can run the Owon VDS1022.
Adrian, I always get transfixed watching you're videos! I really enjoy them, it brings back memories of tracing through circuits to figure them out, back when I was learning how digital circuits work. But please explain: what is a "bodge" wire? Is that a regional term? Where does it come from?! I couldn't understand what you were saying, it's a good thing you made that post where you spelled it out otherwise I would never know! Thanks n advance.... 👌👍
The VDS1022I (the I suffix is very important) is the best cheap scope I've found. For those who can't afford anything more expensive, it will do the job. For me and those I deal with, the 'job' is repairing car amplifiers.
I have the Owon HDS2012S battery operated scope meter with signal generator which is “isolated.” The meter section is definitely isolated from the CPU and USB-C data connector by using a transformer isolated power supply between sections to bridge power. The meter talks to the CPU through opto isolators. The Oscilloscope BNC jacks are plastic and have a metal ring on the inside to contact the fingers on the BNC plug. Obviously, a metal BNC plug is going to be potentially live if whatever it is plugged into is live, so no isolation there. If one uses the included X10 probe which has a plastic outer shell plug, then yes, whatever you are working on will not put voltage on the outer barrel of the probe, a nice feature. An Ohm meter check confirms that the rings inside the BNCs, calibrator ground and USB-C shell are all connected together. Summary: The HDS-2102S meter section is truly isolated. The HDS-2102S oscilloscope section BNCs’ outer shells are isolate your fingertips when using the X10 probe, but the ‘scope is not isolated from ground if you plug something into the USB-C or clip the calibrator to ground. Owon is a little more expensive than similar Chinese budget test equipment, but the quality is better and worth the slight extra cost.
The sample rate is tied to the seconds per division so that your sample depth (5K samples) takes up the full width of the display. The shorter the time between divisions, the faster it has to sample. I'll bet you this thing has a small RAM buffer. There's no way it can stream continuously at 100M samples per second over USB 2. So it is probably buffering up one screen's worth at a time, then sending it over USB for display. Then it grabs another screen's worth. My Analog Discovery 2 does something similar, though I think it can buffer a little more than a screen width at a time. The lack of direct control over the sampling frequency can be annoying when your signal is near the scope's maximum bandwidth. If the sample rate isn't a multiple of the signal frequency, then you can get a different number of samples on two consecutive periods, which can make it harder to post-process the raw sample data. It can also cause interesting artifacts with interpolation.
I know lots of people don't like PC-based scopes but I'm also a big fan of the Analog Discovery 2. It really doesn't have *that many* limitations, given I work on sonar so I'm not dealing with high-freq RF stuff. And you can do *so many* other things with it.
The mouse wheel over a drop-down control is an innate Windows thing. So it's no surprise it works in the menu but not on the display. That would require extra programming. Besides that, the program needs to know if scroll wheel=zoom or scroll wheel=amplitude.
_"That would require extra programming"_ -- barely. A properly-written program would already have the scrolling behavior broken out into its own function, so it'd be simply a matter of adding that one region of the window to the handling of the mouse-scroll window message. It'd literally be one, maybe two lines of code. You're right that in the waveform area of the window, it is ambiguous what the user might want. But GUIs deal with ambiguity all the time; that's an imminently solvable problem. The most common is to have one be the default, and then use a modifier key (e.g. "shift") to do the other thing. Alternatively, there could be a toggle button on the window that selects what the mouse wheel does. Either way, the potential ambiguity isn't a reason to skip the feature altogether.
The diag cart showing the control port as "BAD" is typical on a Rev. A. board; there's a part with a different value in the paddle circuit - don't remember if it's a capacitor or resistor - but it doesn't affect functionality. My own Rev. A. board shows the same "failure" but paddles work fine anyway.
USB isolator modules based on Analog Devices ADUM isolation chips are avaiable on eBay etc. Allow DC isolation and power injection or powering from host via DC-DC isolated convertor module. Very useful for audio DACs, hubs etc...plus this scope module.
The isolation, if there is any at all, will be on the USB port only. There will not be any isolation between the two channels on a scope in this price bracket.
The grounds of both probes are connected together, both referenced to each other. The scope ground will be referenced to USB ground. You won't have much of a USB port left if you connect either negative scope lead to a non-grounded point in the device under test 😀😀
Commodore 64s are so great for testing osciloscopes because of their normally "dirty" signals with well defined patterns from the passives that are designes specifically for targeted mitigation of the noise, bounces and other behavior instead of complete nullification found in some other systems. They also have a variety of frequencies inside.
I noticed 'made by Lilliput' on the case, that may be the same manufacturer that has made smaller LCDs for decades. Their LCDs were popular back in the mid 2000s.
I recall a TTL shortage in the mid-80s. It's possible that even Commodore was having trouble sourcing some of the chips it needed and was getting them from various sources, including old stock…
I guess it may fail to work after in someone's home, later back to factory, repaired and re-sale as "refurbished". As a teenage in the 80's, I've seen the assembly line full of auntie working on the soldering, can't blame their quality since they're not well trained.
Yeah it's quite possible. It's really funny as even the early Rev A boards that I've worked on have a RF shield soldered onto the bottom -- and this board had no evidence of that at all. So many mysteries
Half of your complaints are based on not using multiple channels. Having to hover over a setting based on the channel makes more sense when there are more channels visible. Rolling your scroll-wheel in the grid when showing multiple channels would be an exercise in annoyance of guessing which channel would be adjusted. It's not perfect, but would work for up to 6 channels with no changes (a requirement for cheap software). And you get what you pay for :) If I needed a scope like this, I would buy this one
In addition to isolating probes, you can get a USB Isolator, which will isolate the scope's ground from the host PC's ground via a USB dongle, but I would just pay extra for the isolation here since you'd potentially need two isolators due to the (terrible) non-standard USB power-tap cable.
@@mrfrenzy. Of course, I'm just speaking for how to turn any standard USB scope you might already have into an isolated USB scope. As I said, when buying this one, it would be cheaper just to buy the isolated model, rather than isolating it after the fact.
I had an Amiga 2000. I upgraded the CPU, (to...I don't remember...but it was different looking) and maxed out the RAM at 9 MB. Used it for a midi studio. Never got the toaster though...Those things really did revolutionize the in house ability for many local TV networks. Never did use a CD Rom or hard drive. Just 2 Floppy drives. Oh yeah, but with that large amount of RAM I did figure out how to set up the RAM drive ability. That thing was fast........ Much simpler times... Oh...and I know what you what you mean about the scroll wheel. My first Microsoft PC, a Packard Bell-Win 95 then 98se, I had bought TurboCad and that was my first experience with scrolling-zoom. Later when looking for a good paint program I chose Jasc Paint Shop Pro over Adobe Photoshop simply because Photoshop did not do the scrolling-zoom. "What the Hehhlo"!
Drean Company from Argentina licensed CBM to produce C64's out of motherboards discarded in factories due to being too expensive (in terms of time) to repair. Rev A (326298) motheboards mostly. The funny thing is they repaired AND modded EVERY motherboard to 6 pin DIN Video Connector to support Luma-Chorma output, using that same bodge wire (even the same red color...) I could say that was a "Drean Commodore 64" machine if it wasn't for the different case badge and VIC-II chip (We had our own 6572 PAL-N VIC II).
Follow-up: I actually had never looked at the Rev A C64 video output circuit on the schematics before. It turns out the RF modulator is not part of the Chrome/Luma processing at all on this revision. (It's the only one that's like this.) See the top right part of this schematic: www.zimmers.net/anonftp/pub/cbm/schematics/computers/c64/326106-2of2.gif
That means this mod surely worked OK at some point. I think the issue I was seeing with the luma signal being super low was due to bad soldering or broken traces because the rework done was bad. When I restored the board back to the original 5-pin connector, I fixed a few traces with bodge wires near the video connector and now everything is back to original condition. (I also restored R10 to be 120 ohm as specified on the schematic. It was 300 ohms on this machine.)
Ideally, a RF modulator replacement could be created to output S-Video and Audio but this would require a could bodge wires running to FB14 and FB15 near the VIC-II. Also ideally the entire original video output circuit should be disconnected and a new composite feed be fed into the DIN-5 from the new RF modulator board. See Mark's video here: th-cam.com/video/LB2gtMQyjqQ/w-d-xo.html
Ever checked out the BitScope units? I've been eyeing one up because the software looks really interesting. Besides normal o-scope stuff, it can also do data logging.
Thanks again for another great video. I need to go dig the C64 out of my parents basement to see what Rev it is. :)
There are keyboard shortcuts mentioned, try using arrow keys.
Adrian, I have the same 326298 Rev A board, but with the original heat sink. The back has the same red and black bodge wires installed the same way as yours, and an 8 pin video connector. I got this board back in the late 80’s when I worked for a computer store in Connecticut repairing Commodore and Atari PCs. I also got some spare parts, 4 boards in various rework condition, a case with keyboard and a spare broken keyboard. I’ve been repairing my own personal C64 with a 250407 which is still stuck on black screen, fighting me every step of the way. I repaired 2 of my extra boards, both 250425 and installed one in a case, the other I socketed out as a test bed trying to repair my original C64 board. I socketed every chip in the 250407 board and every chip from it passes diagnostic test in both of my 250425 boards. Still stumped.
Hey! This exact scope helps me make money almost every day. I repair power invertors and it is essential for getting fast reliable repairs out. Regards from far Ukraine
your not touching my inverter with that piece of junk. go get a techtronicks
I understand that because 80 dollar is a lot of money in your country. I repair too for a living but I am happy I do not have to use this thing. But it is better a nothing. I would stay away from inverters. I use a HV diff probe for working on inverters.
@@jessihawkins9116 brilliant trolling from someone who can’t even spell Techtronix 🤣
@@pa4tim it's isolated, so it's perfectly fine for dealing with invertors. I would use an extra USB isolator though
@@julias-shed I use my techtronicks ossilloscope and flook meter every day 😃
I don't know what YT video creator is worse for my gear acquisition syndrome - you or Mat from Techmoan! Great content and I look forward to seeing you use this scope on more projects.
For me, the e-waste container dictates my gear acquisition :-) and my collection isn't half bad.
i want your e waste Container ngl.@@senilyDeluxe
Hi Adrian you did a great interview on the The Retro Hour (Retro Gaming Podcast) this week. Thank you for sharing your early years with us and how you became interested in electronics.
Cheers Tim
You need 2 things:
1. A real name
2. MorePower!!!!!11!
Thank you so much for this review! When I first time saw it (a year ago) I immediately decided that I need this oscilloscope. Now, when I bought it and it finally arrived, I'm watching you review again with a pleasure of being able to try everything and use it. Thanks again for such a great review!
I bought this as my first ever scope after seeing lots of reviews, and I'm happy with it for the very occasional times I need a scope. Yeah the software is kind of infuriating although the github version fixes some of those annoyances. But the UI as a whole could be a lot better, making use of the large screen of a laptop to lay out more immediate controls instead of requiring menu diving. But as you say, the scope itself seems very capable, fast and accurate, and that's surely the most important thing.
I do enjoy seeing all of these cheap scopes as options, especially for beginners. 11 year-old me would have adored one of these on my electronics bench in the late 1980s!
I personally ended up buying a standalone Siglent SDS1104X-U because I needed something that could do a little more and was a little bit more reliable, as well as four channel. I kind of wish I had sprung for the -E Model as it has a port to add a digital logic analyzer to it, but I didn't really have the money at the time.
I have the SDS1104X-E. I wouldn't be too unhappy about not getting the E model. The logic analyzer is rather pricey (almost as much as the scope) and, from what I read, not all that great (missing trigger off digital options, for example). Makes sense - the digital module isn't like other scopes where all the logic is in the scope and the pod is just buffering/signal conditioning. Have to step up to the SDS2104X-Plus to get a more digital logic analyzer setup. Its definitely a much nicer scope, but quite a bit more expensive. I'm happy with my SDS1104X-E - it's alot of scope for the price.
That analysis of the video signal was amazing.
i have the non-isolated version since about 5 or 6 years ago (haven't used it much, though); the software is java and, at least when I got it, it came with source code (possibly by mistake), at the time some people were trying to make it work on linux, IIRC, it's great that now there's opensource software for it!
Hope he notices your comment!
@@joveaaron-real Yep looks like github has some unofficial release that looks a lot better.
Nice! Hope somebody’s translating that to C++.
@@nickwallette6201 Well, we can be thankful that at least it's not python.
Where?
I recently bought an Owon handheld scope and I am quite impressed. It's a great little instrument and being isolated from ground is a huge bonus.
Isolation is a really big plus. On the other end of the spectrum are oscilloscopes that connect ground of the DUT with the ground of your expensive laptop/desktop computer. Why even bother with USB oscilloscopes...
I have the 100mhz model with built in awg. It's such a handy piece of kit to have in my bag as a service engineer. I highly suggest upgrading the leads. I use Probemasters (DMM and scope) with mine.
@@graealex in the US laptops are cheap. I can get a used one for $20 or free. If you're hooking USB scopes to your expensive computer that's really your fault.
@@H0mework I don't think you actually get the problem here.
If you play a little with the software and learn the "shortcuts" this thing it's a beast! It's really fast and the open source Software it's like a candy!
PS. Great work as always!
The 57 dollar scope you showed has been a nice addition to my bench. I grab it all the time now for quick signal checks. I have several other scopes, but it is super convenient.
At 19:11 you are only seeing a subset of the time/div selections. In the scroll bar move the slider to see, and be able to click on, other rates.
Pro tip: Oscilloscope probes with 1x/10x usually only have their full rated bandwidth at 10x setting.
Working on 5v stuff you can use 10x attenuation with not much added noise and it may sharpen those waveforms up a bit.
Yes, Dave Jones did a nice video explaining: th-cam.com/video/OiAmER1OJh4/w-d-xo.html
The open source software interface for this scope you linked in the description is definitely better than Owon's. Has a little more functionality and control. Will allow you to use the scope on Linux too.
Linux mentioned... Instant buy... :)
Thank you for pointing that out...
@@theserpentes I can confirm!! It works flawless on Ubuntu 22.04!! Basically it's really better than Owon's for Windows.
The scope reads UOMO when it was upside down on camera - "Man" in Italian LOL. Nice video, I like how you manage to mix the new equipment with an actual repair! The scope looks very good to me - the UI is improvable but I guess you can get used to it. What really matters is that for only $80 you get what seems to be a very capable hardware!
Seeing you happy and laughing is the best for us all. I think you have a great humour for the group cinema watching, sadly you don't do live streaming of such.
Adrian, I know the interface frustrates you, maybe because it isn’t more standardized but from working in industry (Westinghouse and Kodak), every time we purchased a new sophisticated piece of test equipment, they all had complex unusual interfaces and a long learning curve. I think this little oscope is very capable, you just have to get over the hump in the learning curve! Great review!
I think you had a predecessor like yourself who modded up that gen 1 c64!
Another thought, I’ve never used a SW based scope like this, so learning the interface would seem “normal” to me!
Yeah it's kind-of annoying. People think everything should work the way they know, but there is no rule that says every same category software HAS work the same.
You can't even jump from EDAs without learning the others first, unless you want to be super inefficient, ie, slow. I watched a 1hr KiCAD vid and knew more than EEVblog fumbling around for 4hrs saying KiCAD was rubbish, when he didn't even know it. Basically, if it's a different program, it's going to have a different way to do things, ie, RTFM beforehand - lol -.
I would laugh if this SW could do everything he wanted using shortcut keys, just because he didn't look up help - lol -.
@@SidneyCritic I agree that you for sure should spend time learning new test gear, however there is no excuse for not making the software easier by leaving user inputs unused.
For example with the mouse pointer above the waveform the mouse wheel should do SOMETHING, having it do NOTHING is just lazy programming.
The same goes for the right and left mouse buttons when hovering over different things.
I have the VDS6104 and it's great, in fact they have already fixed all the things mentioned in there, you can scroll on the waveform, right click and drag the waveform, right click the channel markers to reset etc etc.
@@mrfrenzy. Conventual is better, because if you don't use unconventual for a long time you forget how to use it, but there could be reasons why it isn't conventual, eg, they just don't know.
Just looking at the manual there are shortcut keys. ADB should've read the manual - lol -.
@@mrfrenzy. It seems there are quite some keyboard shortcuts though, but this implies they want you to use both the mouse, keyboard and lead with 3 hands.... idk how that works?
@@SidneyCritic Yeah I commented and linked to the file showcasing them just before.
Amazing review!!! Just by trying to apply it in real life scenario, thank you!
Love coincidences like this. I've been using this exact model of Owon for the last two days and it's my first o-scope of any kind so I kinda jumped when I saw this video in my feed. You wouldn't believe how embarrassingly long it took me to realise the hook portion of the probe just pulled off and I struggled with hours using it with the hook on
I could remember this Mods. I live in Germany and that was described in magazines. It was an series starting low level things and gaining the higher thinking.
The voltage mod I have made together with a small peach of copper that I had.
And the mod with the Luna mod I remember. They had a special monitor in the lab and did not thought about that a normal monitor is not so sensitive.
Two weeks later they explain the mistake.
As the mods began to be revealed that is exactly what I thought, "These mods were done by an enthusiast at home with limited skills and equipment" and a magazine of the day would be the exact place the information came from.
brilliant intro to the OWON. I bought one and was struggling with the interface like you. Good to get a second opinion on the hardware though.
Saving the waveform is actually really useful. You save it and use it on a signal generator to reproduce the same waveform.
As a modular synth user... I see the value in that...
Good point.
Also you can save waveforms and give them to the customer with receipts-- if you are using it for repair work.
*laughs in Serum* 😂@@jazzdirt
As a beginner I learned so much from this about using oscilloscopes in general. What an amazing level of knowledge you have! Inspirational!
I was told once that the hardest software to learn is the second one. (in reference to CAD in my case) once you get used to something you get frustrated when it's not where you expect.
Well... the problem Adrian's is experiencing is largely that this software doesn't comply with current norms of UI expectations.
You'd expect you can just "zoom in" on an element, because that's how most other software is. The current model for any visual element is to treat it like a physical object with the ability to change things right on the object rather than having to go into an obscure menu somewhere. When it doesn't behave like that, people say it's "non-intuitive".
In other words, intuition is built upon how you've experienced other software. If suddenly everyone has the little gear icon in a UI and it represents settings, then that becomes intuitive. If a designer expects you to do everything backwards from the way everyone else does it, that's not a great UI design.
@@stevesetherThere is good open source software for VDS1022 so I guess Owon doesn't spend time improving the official software for this old scope.
The official VDS6104 software is quite good, zooming, right clicking etc on wave form and channel levels works as expected.
@@mrfrenzy. I couldn't find anything that looked like the UI was fully OSS.
From what I can tell the software on Github in Adrians link is largely compiled Java classes pulled from the EXE, combined with firmware pulled from the EXE.
Is their some OSS software for this I'm missing, or is the Java UI source available? the only java source in that Guthub repo is a small wrapper for a C library that interfaces the USB.
@@stevesether I don't think using an unmodified scroll wheel to zoom is intuitive. On the other hand, using the scroll wheel over a value is expected to change that value. If the scroll wheel is to zoom in the waveform I would expect you to need modifier keys. Probably one key for horizontal and one for vertical.
I have it and I love it ! For this low price , it's the best choice for beginners . I use with a old PC , a kind of notebook with 10"" screen and it make the job for me !
Very good choice !!!
The keyboard shortcuts for adjusting the horizontal and vertical scales make this scope much easier to use. At 11:31 in the video the “tips” menu in the Owon software has a tab for these. It takes less than 1 minute to learn them.
Florentbr’s version is better, and has even more keyboard shortcuts.
Newark/Farnell also sell versions under their Multicomp Pro brand. They are usually more expensive, but sometimes are on sale. I picked up the non-isolated version from Newark for $56 US in early January.
So, as usual, RTFM applies :)
I don't know how I ended up here but I did watch through to the end.
Oh, it was the oscilloscope. I'm looking to purchase one and really taking my time about it...looking and listening...
Thx for the review, I will stay with my Opensource DIY scopes and Hantec with Opensource Software :)
That voltage regulator relocation job is just _chef's kiss_
At work, when we need to remove epoxy, we use a heat gun which softens it up enough to let us get an Xacto knife or pointed implement under the epoxy and lift it off.
I got a Multicomp Pro MP720016 and it's basically a re-branded Owon VDS1022 (non-isolated) so it uses the same software. It's the first scope I've ever owned and functionally it's a good fit for doing hobby electronics. It has good edge triggering and I also figured out how to capture single trigger events which is very useful.
Nice video. I enjoyed it. Thanks for the scope review.
Hey Adrian, love the videos. An idea for a video that I think a lot of us would love to see, how about a Oscilliscope 101 video. You convinced me that I need one of these in my kit for working on Retro PCs, and when I got it and turned it on I realized that I had no idea how to use it.
This isn't about the content of the video, but every time I watch one of your (very amazing, long time viewer, big time fan, love your stuff) videos when it gets to the intro I expect a skip button to appear because it's so iconic it's logged in my mind as television.
23:15 Are we sure there are no keyboard modifiers to the mouse wheel/drag, like Shift / Ctrl / Alt or some combination thereof to get Zoom, etc?
Yeah I tried everything -- at least everything logical :-)
@@adriansdigitalbasement try pressing M :)
You have to read the Instruction Manual rather than randomly "trying things".
One of your best videos yet! 👍
Haha. A software guy here. The GUI environment used for the interface defaults to handling mouse clicks in the "current window," which in this case is the last one where interaction happened. Handling at top level as you wish is certainly possible, but requires fiddly extra effort. I guess they haven't done that. Thanks for a great pointer. Was looking for a usable cheap scope. Guess I'll give this a try.
My Rev A has the same Video modification. The Chroma Luma video works on it, I don't know if there was more to it than just the jack mod and wires which are done in a very similar way on mine. Maybe there is a portion of the mod that wasn't completed on the one you have? It is also a bit of an odd board otherwise. I think someone cared about it at one point, but it had been mistreated in the years before I got it. I may be mistaken, but I believe that board doesn't pass the Composite video through the RF Modulator. Ray Carlsen has a fix for R10 to bring the video level up on that model board, as you mentioned it was light.
It is cool seeing another of those boards with the video mod. To bad it doesn't seem to work properly on yours.
Sounds like it would be good to get to the bottom of the chroma luma mod.
Another advantage of an isolated scope is that it allows measurement of differential signals.
This would otherwise require 2 probes/channels to measure both single ended signals...
I will need to (partly) disagree with you. Even with an isolated oscilloscope you want the ground probes to be connected to an RF ground, otherwise the shielding becomes a giant antenna. For sensitive signals that could be a problem.
@@eDoc2020 I agree, it really depends on the situation. Had a use cases in mind such as RS48/CAN or voltage transitions over components where the frequencies aren’t that high.
As usual in electronics, you need to your wits….
I am enjoying your channel. Thanks!
I have this scope and it works on a mac and linux, software and method to get it working is a little more involved.
Turns out the software is Java based, and all you have to do(from what I can remember) is install Java for MacOS, run the executable for windows. The only real hard part is getting the USB working which wasn't hard on my 2021 M1 imac, which has a stubborn USB in its own right.
Otherwise, once you get the software up n running, the scope is great for basic stuff as shown in the vid.
I hope this info is helpful for a fellow mac/linux user.
Edit: I had no issues getting zoom to work with mouse on this.
I'm an Atari guy but I always enjoy your videos!
I'm really enjoying your cheap scope reviews, hope it doesn't drive you mad! I liked your almost thumbs up review system too. I survive on my USB 2CH Hantek using the hScope app for my phone, but would like to change up, this could be a nice little upgrade. Cheers!
Thanks for the video and showing off this little bugger, Adrian:)
Suggestion: Always use your google-fu with the keywords + "community software" ... as an insider tip.
Oh and even better: Do that BEFORE you buy such a soapbox, hehehe:) (Not directed at you. You obviously made a product review. But to the other clueless ones out there, including me:P)
I would like to add some feedback from the perspective of someone who knows nothing about oscilloscopes, but is at the point where considering acquiring such a device to further knowledge and capability.
First, I have gained the intuition that this two part solution, the sampling device and computer, is the future for enthusiasts. Only the software holding this evolution back.
Second, by reviewing such a device using actual use case and practical example, you provide an oscilloscope fundamentals tutorial with key areas that stuck in my memory model way better than just working principle in theory alone could have done.
Thank you, and I hope this feedback is of value when considering the impact of such enthusiast videos as yours on your viewers. Definitely learned a few things today.
Way back when I worked in manufacturing, I used to touch up the circuit boards that came out of wave soldering. We would insert headers and things that couldn't otherwise survive the trip through the wave soldering machine and we also installed ECO wires. When we installed wires, we would use some "super glue" to hold the wires in place and route them neatly, or at least I did the neat routing at the time. Once our wires were installed, we used some De-Sol as it was called to remove the extra flux and we then trimmed up any extra pins and inspected for solder shorts.
When I finally became a tech, I was quite proficient at replacing chips due to my touch-up experience and I can proudly say that there was little difference between my chip removal and hand soldering compared to what was done on the manufacturing side. Sadly, this wasn't the case for all the techs and many ruined boards very badly as was the case with field returns. This was a common occurrence when I worked in field service where I received circuit boards and equipment that was already 8 or 10 years old. With those boards, some dating back to the mid to late 1970s, the pads were ripped and wire-wrap wire, or bus wire as we called it, was a common sight on the backs.
When I received those boards back from the field, I learned quickly enough to check for that before even powering up the boards because in many cases, it was these poor repairs that were causing the more recent problems due to cold solder joints or intermittent breaks in the copper traces.
Those USB scopes are amazing critters compared to the old Tektronix 465B which I was so accustomed to.
Regarding isolation, even with low DC you might have a problem if you want to probe in reference to something other than ground. Not usually something you'd do but sometimes you need to.
Good point. I've found it useful to probe some circuits that have low-side switches in their power circuits and the scope would be bypassing that switch entirely and causing the circuit to always be on. I've also got some isolated TTL UART to USB adapters my company made for our test jigs. Very useful.
Not really a problem when the usb side is isolated. At that point it is the same as a battery scope or even a multimeter. What you can't do is probe two different points with different reference commons.
I am glad you not only show toy scopes (but I am not an Owen fan) The scope is the eye of the electronics repair person, that is why it is my most expensive bit of kit. I use a R&S 300 MHz scope. Beside that an isolated scope meter from siglent, not a bad scope but the UI is bad, triggering is pretty good and rhat is very important . A scope is nice but a lot of uers have no clue how to use it. Fine for checking ripple on power rails but you can do so much more
I put an audio out on something and recorded the oscillation in Audacity (free software). The zoom is amazing. It doesn't work above hearing range, but the perk is to hear it as well.
Yep, and you can inspect individual sample amplitudes.
Most of the ui related problem you had are easy to solve by using the keyboard shortcuts. (Change timebase,v/div,trigger,)
And all the triggering are done in hardware. The scope has an FPGA that handles that
I have one of these scopes, and I agree that it is very capable for a reasonable price. It found the problem I was looking for in a 675kB/s RS485 system with no difficulty.
For a lot of apps like that, sometimes you have to hold control/shift when scrolling the mousewheel to select the type of zoom you're after (eg; zoom, scroll, etc)
Was kinda yelling at Adrian about this - though it's possible he tried it without saying
@@Blitterbug either way, he sold me on getting that as my ideal oscilloscope for any kind of work that I end up doing. Pair that with a $250 HP netbook and you're golden (netbook, not a Chromebook. Runs full fat Windows 10)-- 128 gig eMMC ssd soldered to the main board, 4-8 gigs of RAM, and a dual core i3, little 13-in screen, but it does 1080, I own two of them and they are fantastic little on-the-go machines
One of my favorite things about those HP netbooks is their keyboards, you would think it's some squishy cheap piece of shit, but it's actually really satisfying to type on. Much better than my $3,500 razer blade pro's keyboard for sure.
At 4:41, you say that the AC voltages in a PC are isolated from the AC supply. I'm not a pro, but I didn't think there were any AC lines inside a PC, at least a modern one. At least from the ATX spec and later, all internal power inside a PC is DC, right? Do some older machines have a 12V AC line as well? I just didn't think that AC would be of any use inside modern transistor based processors. But I'd be curious to know if that's untrue!
It's all about what that DC is REFERENCED to. Say you have the "Zero Volt" rail (black ATX wires), and you call that the "DC Reference voltage". Now when you have a +12V wire, that's 12V higher than the reference, +5V which is 5V higher than reference, etc.
However if you make the 5V rail your reference, then the 12V rail will measure 7V... that is because both the 5V rail and the 12V rail are referenced to the same "zero volt" rail. They are not isolated from each other, they share a common "ground".
In a PC power supply, the "zero volt" rail may or may not be fully isolated from the mains power. The first thing that happens is that the Mains AC gets rectified using 4 diodes, to create a high voltage DC (120V AC >> 170V DC or 220V AC >> 310V DC).
So, we have a fairly high DC voltage, which then gets converted to DC by the ATX PSU.
The trick comes with the Mains Earth (Ground), which is actually connected to AC Neutral. The ATX PSU will be grounded, and that means that the chassis of the computer will be at AC Neutral. If the motherboard or any other component connects the DC "Ground" to the chassis "Ground", then the ground is now referenced directly to Mains.
None of that matters if your scope probe is connected to an equal "ground". However if you connect the negative probe to a point which is higher, then power can flow out that scope wire and back to the mains. It loops around and creates a literal short circuit.
For example, let's say you want to check the voltage of a power supply after the bridge rectifier. There is a smoothing capacitor rated 400V DC so you connect your scope lead onto the Negative terminal and... BOOM. That's because the Capacitor "ground" is not really at "zero volts" like the chassis ground or scope ground might be.
Sorry, that was not well written, and it's very hard to explain here.... hope that gives you a few hints.
Maybe the infinite persistence setting has a limit to the number of traces it can store. When that counter wraps around, it would overwrite the previous traces stored there.
It looked like the major signal got quite bright, and the signals that happened less frequently would disappear after a while.
Gotta get one of these! I think that the menu window is actually quite intuitive and quite effective in my opinion.
I would like to see you take another look at that board and do all the mods that would be very interesting
Love the TRS-80 (Model 4?) in the background, that was the first computer I had growing up, I taught myself BASIC on it 🙂
Very interested in being able to measure each line of the video signal, I'm thinking of creating a video mod so it could be useful.
There are a few repaired traces on the bottom of the board where I saw a broken unrepaired trace.
I the back of my mind I'm thinking about this C64 compared to a Raspberry Pi Pico for a project. Astounding how things have changed in 40 years, while some things still similar or at least recognizable. 😃
27:00 For Christmas of 1982, there were many defective units coming off the production line. They were storing those in tractor trailer trucks in the parking lot; however, some of them were actually shipped as the folks picking up the trailers were either not informed that they were filled with defective units. Or, they were purposely shipped just to get the product under the tree for Christmas Morning with the expectation that customers would return them later for replacement. So, I suspect that this unit was a warranty return to Commodore who might have replaced them with working units and serviced the defective units as time permitted over the following couple of years.
The A to A controller would be because the device is technically a switched mode microcontroller board, and can be configured as a host or a client device. However, it should just use Micro-C for this. USB-C mini would also be an option, but that was phased out with USB 3.0 and was even rare before then. (It's a modified USB Mini connector with an additional pin and a slightly different shaped shield. I actually have an adapter that came with my printer's set of 3 inch adapters for hooking up any and every USB camera in existance.)
It also works very well on a not-too-old touchscreen point of sale terminal.
My new bench meter is an Owon, its in my APC UPS video and I really like it. Holds up well to my calibrated TTI
In audio we often use 2xUSB A to 1 USB for separating data and power streams
If Possible, would you do a video to fix the Luma/Chroma on this Rev A board so that the 8 pin dim works? I have a 5 pin dim that I would like to convert to an 8 pin dim.
dim = DIN?
@@serpent213 You are correct
This looks like what I need for when I need to show waveforms on my TH-cam channel. It's not going to be as capable as my Tektronix bench 'scope but for a lot of signals it's quite good enough.
Great scope .. on time and packed well. Did I mention Great scope
Great video as always, hopefully this will get an open source treatment as well, seeing how good/capable the hardware is.
Also looking forward to the live stream 😊
A few people already mentioned this open source software does exist! So I'll need to do another repair with this software: github.com/florentbr/OWON-VDS1022
@@adriansdigitalbasement Can't wait to see a follow up :)
@@adriansdigitalbasement The Github version adds mouse scroll wheel zoom on the time/div. Lastly, there is android application called HScope that supports the VDS1022 with an on the go cable. So a phone or tablet that supports OTG can run the Owon VDS1022.
@Simr Khera patreon
Adrian, that same 4066 fault weirdness also occurs with the diagnostic on sx-64s occasionally, probably some sort of intermittent timing issue.
Adrian, I always get transfixed watching you're videos! I really enjoy them, it brings back memories of tracing through circuits to figure them out, back when I was learning how digital circuits work.
But please explain: what is a "bodge" wire? Is that a regional term? Where does it come from?!
I couldn't understand what you were saying, it's a good thing you made that post where you spelled it out otherwise I would never know!
Thanks n advance.... 👌👍
Where does the power connector go? That's right. In the square hole.
It seems OWON has a page with software and user manual. So mayby they have updated software there.
The VDS1022I (the I suffix is very important) is the best cheap scope I've found. For those who can't afford anything more expensive, it will do the job. For me and those I deal with, the 'job' is repairing car amplifiers.
I have the Owon HDS2012S battery operated scope meter with signal generator which is “isolated.” The meter section is definitely isolated from the CPU and USB-C data connector by using a transformer isolated power supply between sections to bridge power. The meter talks to the CPU through opto isolators. The Oscilloscope BNC jacks are plastic and have a metal ring on the inside to contact the fingers on the BNC plug. Obviously, a metal BNC plug is going to be potentially live if whatever it is plugged into is live, so no isolation there. If one uses the included X10 probe which has a plastic outer shell plug, then yes, whatever you are working on will not put voltage on the outer barrel of the probe, a nice feature. An Ohm meter check confirms that the rings inside the BNCs, calibrator ground and USB-C shell are all connected together.
Summary: The HDS-2102S meter section is truly isolated. The HDS-2102S oscilloscope section BNCs’ outer shells are isolate your fingertips when using the X10 probe, but the ‘scope is not isolated from ground if you plug something into the USB-C or clip the calibrator to ground.
Owon is a little more expensive than similar Chinese budget test equipment, but the quality is better and worth the slight extra cost.
Cheers Adrian.
The sample rate is tied to the seconds per division so that your sample depth (5K samples) takes up the full width of the display. The shorter the time between divisions, the faster it has to sample.
I'll bet you this thing has a small RAM buffer. There's no way it can stream continuously at 100M samples per second over USB 2. So it is probably buffering up one screen's worth at a time, then sending it over USB for display. Then it grabs another screen's worth.
My Analog Discovery 2 does something similar, though I think it can buffer a little more than a screen width at a time.
The lack of direct control over the sampling frequency can be annoying when your signal is near the scope's maximum bandwidth. If the sample rate isn't a multiple of the signal frequency, then you can get a different number of samples on two consecutive periods, which can make it harder to post-process the raw sample data. It can also cause interesting artifacts with interpolation.
I know lots of people don't like PC-based scopes but I'm also a big fan of the Analog Discovery 2. It really doesn't have *that many* limitations, given I work on sonar so I'm not dealing with high-freq RF stuff. And you can do *so many* other things with it.
Sigrok has OWON SDS on their planned list.
That means a standard interface that supports almost all oscilloscopes you could want to use...
Isnt SDS a different series? Anyways i would love if this oscilloscope gets supported.
Keep up the good work ... Regards Bob ( London UK )
The mouse wheel over a drop-down control is an innate Windows thing. So it's no surprise it works in the menu but not on the display. That would require extra programming. Besides that, the program needs to know if scroll wheel=zoom or scroll wheel=amplitude.
_"That would require extra programming"_ -- barely. A properly-written program would already have the scrolling behavior broken out into its own function, so it'd be simply a matter of adding that one region of the window to the handling of the mouse-scroll window message. It'd literally be one, maybe two lines of code.
You're right that in the waveform area of the window, it is ambiguous what the user might want. But GUIs deal with ambiguity all the time; that's an imminently solvable problem. The most common is to have one be the default, and then use a modifier key (e.g. "shift") to do the other thing. Alternatively, there could be a toggle button on the window that selects what the mouse wheel does. Either way, the potential ambiguity isn't a reason to skip the feature altogether.
Apparently the OpenSource software has use-definable keyboard and mouse functions.
The diag cart showing the control port as "BAD" is typical on a Rev. A. board; there's a part with a different value in the paddle circuit - don't remember if it's a capacitor or resistor - but it doesn't affect functionality. My own Rev. A. board shows the same "failure" but paddles work fine anyway.
I own a VDS1022I and I find it very useful... I guess now I need to go grab a copy of the open source software and check it out ;-)
Great review. thanks.
USB isolator modules based on Analog Devices ADUM isolation chips are avaiable on eBay etc. Allow DC isolation and power injection or powering from host via DC-DC isolated convertor module. Very useful for audio DACs, hubs etc...plus this scope module.
I was able to find linux soft for Owon. There are also open source ones which suppose to work with it.
2/3's thumbs up. Not a ringing endorsement, but not a death knell either. 🙂
The isolation, if there is any at all, will be on the USB port only. There will not be any isolation between the two channels on a scope in this price bracket.
The grounds of both probes are connected together, both referenced to each other. The scope ground will be referenced to USB ground. You won't have much of a USB port left if you connect either negative scope lead to a non-grounded point in the device under test 😀😀
What I like is that it does FFT analysis, a function which would have cost a couple of thousands bucks some years ago
Commodore 64s are so great for testing osciloscopes because of their normally "dirty" signals with well defined patterns from the passives that are designes specifically for targeted mitigation of the noise, bounces and other behavior instead of complete nullification found in some other systems. They also have a variety of frequencies inside.
31:59 it looks like the left re-soldered trace is broken
I noticed 'made by Lilliput' on the case, that may be the same manufacturer that has made smaller LCDs for decades. Their LCDs were popular back in the mid 2000s.
I recall a TTL shortage in the mid-80s. It's possible that even Commodore was having trouble sourcing some of the chips it needed and was getting them from various sources, including old stock…
I guess it may fail to work after in someone's home, later back to factory, repaired and re-sale as "refurbished". As a teenage in the 80's, I've seen the assembly line full of auntie working on the soldering, can't blame their quality since they're not well trained.
Yeah it's quite possible. It's really funny as even the early Rev A boards that I've worked on have a RF shield soldered onto the bottom -- and this board had no evidence of that at all. So many mysteries
Half of your complaints are based on not using multiple channels. Having to hover over a setting based on the channel makes more sense when there are more channels visible. Rolling your scroll-wheel in the grid when showing multiple channels would be an exercise in annoyance of guessing which channel would be adjusted. It's not perfect, but would work for up to 6 channels with no changes (a requirement for cheap software). And you get what you pay for :) If I needed a scope like this, I would buy this one
In addition to isolating probes, you can get a USB Isolator, which will isolate the scope's ground from the host PC's ground via a USB dongle, but I would just pay extra for the isolation here since you'd potentially need two isolators due to the (terrible) non-standard USB power-tap cable.
I'd bet there is a USB isolator and isolated DC-DC inside the scope already, it would be the cheapest way to make the scope isolated.
@@mrfrenzy. Of course, I'm just speaking for how to turn any standard USB scope you might already have into an isolated USB scope. As I said, when buying this one, it would be cheaper just to buy the isolated model, rather than isolating it after the fact.
When you get a chance, see if you can dock/undock all the mini-windows at the bottom. It may be possible to dock the menus you were using.
I had an Amiga 2000. I upgraded the CPU, (to...I don't remember...but it was different looking) and maxed out the RAM at 9 MB. Used it for a midi studio. Never got the toaster though...Those things really did revolutionize the in house ability for many local TV networks. Never did use a CD Rom or hard drive. Just 2 Floppy drives.
Oh yeah, but with that large amount of RAM I did figure out how to set up the RAM drive ability.
That thing was fast........
Much simpler times...
Oh...and I know what you what you mean about the scroll wheel.
My first Microsoft PC, a Packard Bell-Win 95 then 98se, I had bought TurboCad and that was my first experience with scrolling-zoom. Later when looking for a good paint program I chose Jasc Paint Shop Pro over Adobe Photoshop simply because Photoshop did not do the scrolling-zoom.
"What the Hehhlo"!
Drean Company from Argentina licensed CBM to produce C64's out of motherboards discarded in factories due to being too expensive (in terms of time) to repair. Rev A (326298) motheboards mostly. The funny thing is they repaired AND modded EVERY motherboard to 6 pin DIN Video Connector to support Luma-Chorma output, using that same bodge wire (even the same red color...) I could say that was a "Drean Commodore 64" machine if it wasn't for the different case badge and VIC-II chip (We had our own 6572 PAL-N VIC II).
I see that TRS-80 Model III in the background. It would be hilarious if you had a Rick Roll animation playing on the screen! Lol