I did price this up (all the parts but apart from the resistors and capacitors which can be easily salvaged), it came in at just under $20 The most expensive part is the linear 6V transformer which is roughly 50% of the total cost if you can not salvage one. It did occur to me that it would be better to power the NE555/relay circuit from a small SMPS (rip the PCB from a 5V or 12V power adapter/wallwart) and power just the Tracker pcb from a 6V linear transformer as it needs a 50Hz/60Hz AC supply. That would bring the total build price down under $10 if can salvage the transformer and power adapter. The transistor in the relay drive circuit can be just about any NPN transistor that can handle Ic of 100mA or so (depends on relay coil resistance). If you use a separate SMPS to power the relay switcher circuit you will also avoid the problem of the Oscilloscope trace changing size slightly as the relay switches. As the 'ground' for the relay switcher and the tracer circuits are totally independent/isolated, using a SMPS to power the relay switch, and a linear transformer for the tracker circuit will not cause any problems, in fact the opposite is true - it will work better 😉
You might want to pin this comment so more people can see your price estimate. Replacing the relay with a semiconductor mux will be a bit of a problem at 20-40mA it will be suboptimal. HOWEVER you could build a DUAL tracer circuit and have the Y output of the scope switched with a CMOS mux without any trouble as it only sees the scope input impedance as a load. You could implement the side by side compactor suggestion in the same way by having a small DC offset that you add to the X output with a spare MUX switch. Having an indication of which probe is which trace is a nice idea, what I would have considered is to inject a small higher frequency noise or signal to the output signals that would make the second channel fuzzy so you could observe which one was which. Alternately adding a sawtooth signal to the AC drive when testing one channel would cause the line to be 'dotted' on the scope screen. With modern electronics using a micro to generate the waveforms and a power amp to drive the output with over current and power limits would not be too hard to do in volume production for very little money.
Impressive how you keep apologizing for having built such a simple high tech device. Please never stop teaching sir. Thank you for sharing your knowledge with us. Could you make a video designing such a circuit?
Whenever I was at a shop without an Octopus, we just grabbed a 115/120VAC (U.S.) to 6/12VAC transformer to slap one together. wish I still had mine, but is long gone now. Your making me pull out some old parts and make one again. Been DIY'ing and using them since 1974 ...
This is fantastic! I fondly remember the Huntron and how I could not afford it for my shop, but we had one at my other job. This is like 1989.... I love your channel, thank you!
Hi Richard, I just built this Huntron Tracker and I must say it's brilliant. I mostly fix 70s amplifier and I'm hoping it will save a lot of time diagnosing hard to find faults. I was waiting for the PCB Way PCB and parts list, but I have learnt so much now figuring it out and using Veroboard. Thanks again for sharing your knowledge. I eagerly await your new videos. My girlfriend even loves your Car Booty videos! All the best, Craig.
wow I used a Huntron Tracker while fault finding alarm control panels in 1981 for a now defunct manufacturer in Oldham. One of the most useful pieces of test equipment I ever used.
Thanks Richard! I really enjoy your various trouble-shooting YT's. In the early 1970's a friend gave me a rather poor photocopy of pages 23 to 26 from some sort of manual from the Mobile Radio Department General Electric Company, which described how to build this type of device using a 6.3VAC transformer and a 300 ohm & 3K ohm resistor. It was called "The Curve Tracer". The document showed the various waveforms for different components. The page numbers indicate it was part of a GE publication. I built one and still have it, somewhere in the basement. As I remember it even worked as well on a non-triggered O-scope. I really had to dig deep in my archives but I found, and scanned, the original article I didn't know about the Hameg HZ65 & found two very slightly different schematics for it on-line.
Well done Richard ! I did not remember how simple these circuits really were having used them daily back in time. The signal relay should be optimized for a low coil current not to load the transformer. Not a problem as any type of low power signal relay can be used. I would not try opt for a semiconductor relay as this would complicate the circuit too much in favor of the mechanical relay. I'd be a bit careful using the high current setting as this could damage the DUT. In fact I suggest lowering the max current setting to about 100mA.
Yeah I did wonder about that 350mA setting - if reduced to 100mA it would mean I could use a lower wattage resistor as well. I also have a 4th position on the rotary switch to add an extra range if needed.
Absolutely love this video, I know what I'm making this weekend. I've already built 3 V-I curve tracers, but being able to convert one to a 'Huntron' type will be superb. I thanks you most sincerely for sharing your knowledge.
I recently purchased a setchel-carlson triple video monitor, of which only one monitor is working. That gives me a great reason to build this! I find that machines and software work better when they are not overly complicated.
We used these units a while back when I worked at the phone company in the central office. As electronics got more advanced thru the years, we had to stop using them because the voltage on the probs was taking out the cmos chips and some other very low voltage parts. Especially bad on incircuit testing of parts, because you didn't know where the voltage was going to ground thru other connecting parts. We just couldn't take a chance of causing more trouble then we started with.
So essentially it injecting a small signal to a component leg and referencing to ground over a small window of time ( frequency of 50-60 hz) and creating a IV curve . Cheap CCT but could probably be built with an Arduino with more functionality . Interesting project . To try an find out the problem of that amp , I would place different amplitude audio signals and measure harmonic distortion over say 4 amplitudes and 4 frequencies giving a total of 24 measurements. This may tell you were the distortion is occuring in the cycle and if it is a transitive problem or a capacitive or a DC bias . Of course I would measure DC bias voltages of transistors with zero input and you have a great opportunity as you have a working cctv.
5:32 - What you’re describing sounds very similar to what has been dubbed the “Octopus” circuit consisting of: a step down transformer; a resistor; and eight legs (two legs for the mains, two legs as the DUT probes, and two legs each to connect the X and Y channels of an oscilloscope. 25:50 - I’ve noticed that fuses in the milliamp range will have an appreciable resistance (caught me by surprise the first time I saw it). 30:50 - As I suspected. Your fuse rating is in the milliamp range!
A Magnacraft W117-4 is an IC relay that has 8 pins, is internally a reed switch, and doesn't make the clicking of a relay. I have a Huntron Tracker = one of the best tools I have ever used for finding out about unknown components but great for matching components too. Or, as you describe, for finding faults when you have 1 working part and another that isn't working.
I have a Huntron comparator on my bench at work (audio repair shop) which is often helpful, but the loud clicking of the relay drives me nuts. I really need to open it up and see if I can use a quieter relay or use some foam or a different mounting just a mechanically damp the sound a little bit.
That 32mA fuse will have that high resistance, unless the fusible element is made out of silver, then it would be a bit less Years ago I had a problem with the stereo in my work van in that, when I played it at full volume, which I generally do as I'm a rock and metalhead, the sound would distort and cut out terribly. When I was fault-finding, I found the in-line fuse holder to be quite warm. The fuse in it was a 500mA one and when I checked its resistance it was high, I think in the tens of Ohms. I checked a new 500mA fuse in got the same reading. I replaced the fuse with a 1 Amp fuse and that cured the problem. The fuse resistance was dropping the supply voltage proportional to the square of the current being drawn, power in a resistance I SQR R and that was playing havoc with the stereo at high volume.
Most people open up their electronics to see how they’re working, but sir Richard opens up electronics to see how they’re wuuurkin… 😁 reminds me of travelling in the UK when I was a kid. Great video, thanks!
Never heard of a Huntron Tracker before, but then again, there are so many measuring devices out there. A Octopus curve tracer i do know, and once build one on breadboard a few years ago and forgot all about it. Time to get it back on my todo list. 20:26 Instead of using a 555 for triggering the relay, maybe a flashing light (turn signal) relay of a car can be used. When all flashing lights (light bulbs) of a car are okay, the flashing rate is arround 1Hz per second, but when there is less current draw through the flashing light relay due a defective light bulb(s) , the flashing rate goes to 2 or 3Hz per second and the driver will notice the quicker clicking inside the car. These frequencies 1Hz to 3Hz are ideal for our measuring purposes here.
As usual the video and topic is fascinating. I’m starting to find myself browsing through the comments and respect and admire all the different suggestions, explanations, additional knowledge. Every videos comment section has really helped give me a spark that I didn’t know was there. I have an itch that wants to be scratched 😂. Thank you Richard, and thanks to everyone from the professional to the hobbyists for asking and answering questions and providing insight at many levels. ✊
huntron still around you know. price is over the budget of most of us at around 6K. and if you think that is expensive take a look at ABI electronics modules very crazy prices but crazy capable, it seems.
I have a Hameg Analogue oscilloscope. I believe it was one of their last Analogue scopes. That oscilloscope has the component tester built in. Good memories to hear about the Huntron.
Like it ... but that clicking like a car indicator would drive me nuts. I use mine with a USB scope ... put single probe to first test point, hit spacebar to freeze the component shape ... move the same probe to the 2nd test point to be compared, hit spacebar again and you get an instant comparison in silence ... (can also save screen captures of component shapes etc.) ... still an invaluable tool at times ... :)
Richard that was a really interesting video, it really got me thinking about your home built add-on device you made and how it could be used to fix a stereo audio amplifier. What about injecting a 1 kHz signal into input of each channel and then signal tracing the amplifier sections with the switching device and the oscilloscope, comparing waveform in each channel at the same time. Do you think that would help in finding the distortion in the amplifier? by the way Hameg built in the component tester into their range of oscilloscopes.
When I was in the Air Force, we always used a 1 Khz tone to trouble shoot our radio equipment. We injected at a certain db, and then used test points through the system to look for loss or a change in frequency from the usual norms.
The timing issue coming from the supply voltage to the 555 timer varying when larger current is drawn. A regulated suppl y to 555 should alleviate this.
Built one of these,must be 30+ years ago,still use it today,such a simple device,be carefull what you test with it,as it can damage sensitive parts,but if your a quilified electronics engineer you should have no probs. understanding its few limitations.
This type of tester was used quite frequently years ago. Now, however, the current across the probes might be too much for many sensitive solid state devices. Keeping the current to around 3 ma and using a 4066 cmos solid state switch may be an idea.
Back in the "dark ages" around 1972 while I was in the Navy, I was exposed to a device called the "OCTOPUS" that was a single channel IN CIRCUIT component checker. Same device concept LESS moving parts. (still needed an 'O' scope) A JEWEL to use !
May be an odd thing to say, but modern semiconductors are IMHO more resilient than the old stuff. When was the last time you were heatsinking component leads with pliers just to solder a transformer or a diode down without damaging it? Low voltage cmos usually has lower impedances and will shunt a higher voltage no problem. I agree though that what this could use is a bipolar current source and adjustable compliance limit. Sure it would complicate things more, but would cost about the same as it’d use common parts.
Well engineered Octopus mod. An observation / suggestion. The bridge (power for the relay etc) is now effectively across the X/Y and that and the relay / LED load will affect things. Perhaps use a low power LED and an analogue switch / multiplexer or 2 x FETs instead of the relay. A pot or a selector switch instead of the preset so you can set the voltage (low for micros, high for zeners etc) and some sort of voltage display (even if only a simple LED bargraph). Did something similar to my Octopus (no marine life was hurt) many moons ago.
My transformer has two independent 6V windings si it is not exactly in parallel but does load the same transformer primary which effects the voltage slightly on both secondaries. My take on this is to use a (working) salvaged PCB out of a 5V or 12V switch mode power adapter to power the relay switcher. NE555 works with Vcc from 4.5V to 16V. Then get a single 0-6V linear transformer for the tracker circuit. Both are actually isolated from each other by the relay, and have different grounds. As the linear transformer is the single most expensive part, building it as just described is the cheapest option and also prevents the relay current affecting the display slightly.
@@LearnElectronicsRepair Ah, the 'schematic' (38:39) did seem to show the AC input to the bridge (powering the relay) being across the same secondary that is providing the X / Y. Yes, it would be better to use a transformer with two secondaries or a separate PSU / adaptor to power the relay part. You can make you own ss relay using MOSFET's (to avoid the ludicrous leakage and high minimum current of conventional ss relays), you already know a lot about FET circuits.
DiodeGoneWild built up something very similar to this. I think he used an AC wall wart that is fairly common in Europe; these things are mostly unknown to Seppos like me. As for the switching, you said it's low voltage and low current, yeah? A pair of optocouplers would be an ideal substitute for the transistor and relay. EDIT: Since you had the three RCA jacks, you could have dispensed with the switch, all together. ("You could have dispensed with the switch.") Select current by moving the test lead across the three jacks, just as you would select amps or milliamps on a moldymeder. And I would have used banana jacks rather than RCA for everything except the scope output; I'm guessing none of your test leads are shielded to the tip.
I think the relay option is good because a relay contract won't change the characteristics of the test path. A CD4016 or CD4066 might add some unexpected artifacts.
There is one that I had my workgroup at my current company purchase, however... Just want to add a disclaimer that I'm NOT sponsored or compensated in any way by the company who makes them, nor am I expressing nor implying endorsement. With that mentioned, a company called "uCore Electronics" makes several versions with various capabilities. They have a TH-cam channel and their own website where they can be checked out. Speaking on personal experience, V-I testers have worked quite well when it comes to discrete component testing, though may not quite be useful when it comes to LSI IC's. For my own personal repair business, I have a DIY version that uses a combination of my Oscope in X-Y mode, a function generator with variable sine wave outputs, and a power supply. The Mr. Carlson's Lab TH-cam channel has a version that designed that he makes available through his Patreon subscription. Even though commercial versions have limited availability today, there's lots of DIY versions that can be found looking online. Just my .02 cents.
That's fine mate. This version was intended to be possibly the cheapest possible way to build this. I did actually mention using a sine wave generator rather than a liner transformer during the video. When I used the Huntron Tracker in the 80s we were definitely using it to diagnose LSI ICs - basically by the method of comparing a good board and a bad board looking for any differences.
Very Interesting video. I used to use. Huntron many years ago, and was horrified by the prices they command, even for a very old model. I was hoping to find something that used one of the cheap Chinese LCD scope kits and the tracker adaptions as a modern low cost replacement. In your video, another enhancement you could add, is to have an option to switch much more quickly, and then provide X and Y offsets to both channels, so you can display the waveforms alongside each other.
20:50 - A normal fuse with a very low rating will have a notably higher than expected resistance. It might be of interest to see the voltage drop across that fuse.
Hi I think I know a circuit that can be adapted to work for this device . It uses a 555 timer a cmos Dual D flip flop and a cmos quad lateral switch and can run on 9 volt battery I can send you the schematic if your interested.
In the U.S. these are generically called "Octopus Testers" The earliest mention of these I have found was from a Naval training document of the early 1960's.
Video Title changed to include that name, but I can tell you no one called this a curve tracer when they were made, that name must have been invented later. Anyway I hope you like this video
@@LearnElectronicsRepair A curve tracer was a very old piece of test equipment, from the 50s and 60s... Back then it was the only tool available to characterise components, and using one was a highly skilled task, interpreting the shape of the curve and taking measurements from it. These days we have component testers and dmms that do all the hard work for us. They were already largely obsolete by the 70s/80s, which I guess is why you'd not heard the term. It is the sort of thing that gets rediscovered by successive generations as it is occasionally useful to see a visual representation of how a component behaves rather than just the numbers. The Huntron was just one such example, targeted specifically at diagnostics. I recall seeing adverts for it in magazines 'back in the day'. It was one of the many tools that I couldn't afford, that I thought would help me fix stuff. The reality, as you've just demonstrated is that it's knowledge that counts. With enough knowledge you can just build the tools.
@@LearnElectronicsRepair yeah I thought "this is a dual curve tracer". The MAC97A6,412 triac does about 600ma, maybe you want a beefier package. dunno.
Is there a PCB and components kit available for this project? I do not have very much in the way of "scrap" parts and would really like to just build from scratch with new components.
G'day Richard, all your videos are very well explained for a layman like me. Cudos to your abilities. Is there an actual build list or kit available for this product? Keep up the great work
Great device, but I'd look at much smaller relays to start, that clicking sound would drive me absolutely batty in short order.. definitely a cool tool though!
A little note about the oscilloscope. You have an analog one, which is great. But many modern digital scopes exhibit peculiar behaviors, if used in X-Y mode. That as a warning...
I have 3 scopes - two analog and one digital. This would work with any scope that has a functioning X-Y mode. If the designers of digital scopes can't make them properly then I don't see what I can do about that 😋
I've noticed something with THIS channel, mostly. First, I have Business internet, high speed, solid, no glitching. I watch a lot of videos and movies (netflix, etc). Never an issue. But with THIS channel, several of the videos will hesitate with "spinny thing" and worse if I click forward in the video. Other vids don't do that. Hmmmmm
Oh, and I forgot to mention, I have built an octopus made to work with my AWG and it worked fine. It might not work with generators not capable of sourcing the current, or enough of a voltage swing, but mine did the trick in a time of need.
very nice unit, thinking of making one, I noted that the trim pot goes to the black probe (schematic 30:00) and not to the other side of the transformer(your drawing 37:55) it don't seem to make a difference as the circuit works
Yeah I think that is because the value of the resistor on the switch is low in relation to the value of the 1M pot - but it should be made the correct way (at 30:00 as you mention) I will fix this when I order the PCBs from PCBWay
Hi Richard, any chance of a simple diagram of how you implemented the 555 IC, the link you provided seems to show a lot more components than you seem to have used. Thank you for sharing your knowledge with us, Regards form South Africa.
Thank you very much for this informative video about making the "Huntron El Cheapo Clone (HECC)". What if i want to test low voltage ic's like in tv's or in video card's? Would this device damage the circuit or is can simply lower the voltage and reduce further the current? It's maybe an option to extend the usefullness of your device. I'll hope you have a solution and are willing it to share. Have a nice day. Greetings Henk.
It works on the lowest range at 3.5mA and I doubt it would damage anything, but you could easily modify it by changing the resistor values, maybe reduce the highest current range to 100mA as some other have mentioned and use the spare switch position to add a 1mA range? Actually the one I built here uses a 6V transformer instead of 8.2V so you can probably de-rate all the specified test current ranges by about 20%
Hi Richard. Thanks for this video bro! :) If i might ask for your expert advice/cooment. How common are circuits that are identical for comparison in the same device? What other uses and what other types of regular device can this assist with? Also. Can you help us viewers with discounting a benchtop 2/4 channel high frequency O/scope? there's no way the premiums charged for decent spec by scope manufacturers like keysight etc are anywhere near affordable. especially for those of us trying to break the threshold into advancing repair skills on state /disability benefits.
When I was using the Huntron Tracker in the 80s it was really to look for differences between a good and bad identical PCB. That is where these really excel. I'l looking to review some oscilloscopes in the $70-$100 range when I get chance as this seems to be a sweet spot between price and performance.
@@johnnybravo505 Many channels on YT automatically and silently delete comments with URLs. Sometimes Wikipedia and YT links pass through but not always. What is a handy way to pass on information is quoted search string like "github oscilloscope" and then the user gets to filter the results instead of the channel owner having to hope that the link contents do not change to oppose the narrative.
Nice Simple Device - To cut cost why not use a rechargeable £1 1 x 18650 5Volt DC power Bank - No need for 2 x Rectifiers, cutting even more costs. plus if like me you have 13 amp sockets with built in USB 2Amp chargers. Making the Tracer mobile or bench.
Yes - my best suggestion is use a (working) PCB from a SMPS power adapter - 5V or 12V to power the relay switcher (NE555 works form 4.5V -16V, just select a relay with a suitable coil voltage) then use a liner transformer for the tracker. Electrically, the two circuits are isolated, by the relay. This would work better and be even cheaper than my version if can salvage an old power adapter.
@@LearnElectronicsRepair The 1 x 18650 power bank, Comes with an inbuilt 3V7/4V2 to 5V DC Booster - Charger IC that runs at about 4Khz ( I think) & your mains Transformer is 50Hz - For the X Y timing Cycle So with a 2 transistor oscillator and some Caps Filtering we could make a 50 HZ Sign wave. Also use another 2 transistor Oscillator to run at about 1 or 2 HZ one probe to 1 transistor collector the other probe to the second transistor collector No need for a relay - Hartley oscillators - A job for the BC109s Or 2n2222s - What do you think?
Hi Richard, wondering if there is a way to order just 1 PCB from PCBWay rather than 5? I just want 1 board, but it defaults to 5 with no option that I can find to lower that pre-set quantity. Also, how can I order the ruler? It says the ruler requires 50 beans (have no idea what those are or how to gain "bean credit"). Cannot seem to just be able to pay for it normally. Maybe their process has changed since you posted this video over a year ago? By the way, Heathkit made an instrument called the Component Tracer (Heath Model 2232) which was essentially a Huntron Tracker clone for a lot less cost. It allows two separate test probes to be used with A/B/AB sampling capability and two switch-selectable test voltages (5V or 50V). In the AB mode you can super-impose the images in real time rather than dealing with the switching issues and associated noise glitches. The traces are distinguished by one being solid and the other being a dotted line. These devices are available every so often on eBay and often run less than $100.
That you could do replace the NE555 with a bistable multivibrator - in fact I comment before I dismantle it that I can't remember if I used a 555 time or transistor oscillator when i built it.
This is my specialty…. So feel free to ask any questions I’ll help however I can I have a small business and laboratory specializing in component level troubleshooting and repair/calibration of industrial equipment. I specialize in test equipment and other metrology related stuff. I also have a collection of curve tracers, short finders, Huntron trackers, polar “tone-ohm” devices…..and dozens of other troubleshooting type devices. Some of them are built from old DIY schematics from retired HP engineers and elsewhere. Some really interesting stuff So If anyone has any questions about that type of stuff….. feel free to drop a comment or question down below. Lot of experience looking at that type of stuff
So here's a question then; are there any currently manufactured devices that make it easy to measure resistors for noise, Johnson or thermal noise? I took a quick look online and didn't see any such product, and the only time I ever remember reading about it was a do-it-yourself article from nuts and volts magazine a few years ago.
36:24 Hmm - my instincts were bugging me about the resistors being on the black wire and not the red wire; seemed like touching the red wire to the wrong thing could short the transformer. Upon further inspection, though, the bottom side of the transformer isn't "ground", it's just sorta-floating. Is that ok, to have the transformer in such a design not have a fixed reference point?
Is the Scope display flicker difference;... not the finite time the relay contact are in mid position (ie: no man's land) neither connected to 1 or the other...
@@LearnElectronicsRepair im just a noob so havent got the proper solution. all american 5 radio made a simple flip flop circuit, maybe you could adapt it to your needs.
@@garygranato9164 It needs some electronic device which can switch a 50Hz AC signal on and off, conducting 3.5mA - 350mA depending on the range switch, without distorting the AC sine wave. This is beyond my expertise too - I'm a circuit fixer come part time bodger rather than a circuit designer 😉 IMHO the relay works for that purpose just fine until someone convinces me it is cheaper/works better some other way
@@LearnElectronicsRepair You want a triac. Search for 'SSR circuit', they tend to include optical isolation which you don't need but I'm sure you can figure out the details now you know it's a triac you need.
I clicked on the PCBWay ruler link, it gave me error : “ Safari can’t link to the server, because it could not establish a secure link to the server”. ☹️
Would you be able to send me the schematic? Love this project. Currently working on many of the same type switching power supplies. I have one working and the other 20 do not work.
I see 1 Hameg HZ65 ( Zed) for 127 quid on eBay, great project you have there and I certainly learnt something today, will you film yourself creating the PCB ?...cheers.
Yes definitely. I will pass this over to Carlos at Retro Upgrade who is much better than me at PCB design and we will publish a part 2 video (most likely to be on this channel but do check out Retro Upgrade too). th-cam.com/users/RetroUpgrade We'll get some prototype PCB ordered (free thanks to the PCBWay sponsorship deal) and once tested this will be uploaded as a PCBWay shared project for anyone to order. This process will likely take 6-8 weeks, in the meantime feel free to build or improve the 'ghetto version' featured on this video. None of the components are critical so you can just experiment with the design. 🙂 Anyone wanting to build your own sponsored projects with PCBWay, come over to LER discord or email me electronicanaria@outlook.com and I will help facilitate that for you 😉 Learn Electronics Repair is now on Discord! Come and join the fun, it's free. discord.gg/vam6YC8vwU
@@LearnElectronicsRepair Great stuff ! I went to join Discord but was told 'unable to accept invite' dont know much about Discord so will try later...cheers.
@@andymouse Really!!! The discord is open to everyone, if you still have problems please email me elecronicanaria@outlook.com and I will try to help you
I did price this up (all the parts but apart from the resistors and capacitors which can be easily salvaged), it came in at just under $20
The most expensive part is the linear 6V transformer which is roughly 50% of the total cost if you can not salvage one. It did occur to me that it would be better to power the NE555/relay circuit from a small SMPS (rip the PCB from a 5V or 12V power adapter/wallwart) and power just the Tracker pcb from a 6V linear transformer as it needs a 50Hz/60Hz AC supply. That would bring the total build price down under $10 if can salvage the transformer and power adapter. The transistor in the relay drive circuit can be just about any NPN transistor that can handle Ic of 100mA or so (depends on relay coil resistance).
If you use a separate SMPS to power the relay switcher circuit you will also avoid the problem of the Oscilloscope trace changing size slightly as the relay switches. As the 'ground' for the relay switcher and the tracer circuits are totally independent/isolated, using a SMPS to power the relay switch, and a linear transformer for the tracker circuit will not cause any problems, in fact the opposite is true - it will work better 😉
thanks :)
You might want to pin this comment so more people can see your price estimate.
Replacing the relay with a semiconductor mux will be a bit of a problem at 20-40mA it will be suboptimal. HOWEVER you could build a DUAL tracer circuit and have the Y output of the scope switched with a CMOS mux without any trouble as it only sees the scope input impedance as a load.
You could implement the side by side compactor suggestion in the same way by having a small DC offset that you add to the X output with a spare MUX switch.
Having an indication of which probe is which trace is a nice idea, what I would have considered is to inject a small higher frequency noise or signal to the output signals that would make the second channel fuzzy so you could observe which one was which. Alternately adding a sawtooth signal to the AC drive when testing one channel would cause the line to be 'dotted' on the scope screen.
With modern electronics using a micro to generate the waveforms and a power amp to drive the output with over current and power limits would not be too hard to do in volume production for very little money.
Impressive how you keep apologizing for having built such a simple high tech device. Please never stop teaching sir. Thank you for sharing your knowledge with us. Could you make a video designing such a circuit?
Whenever I was at a shop without an Octopus, we just grabbed a 115/120VAC (U.S.) to 6/12VAC transformer to slap one together. wish I still had mine, but is long gone now. Your making me pull out some old parts and make one again. Been DIY'ing and using them since 1974 ...
This is fantastic! I fondly remember the Huntron and how I could not afford it for my shop, but we had one at my other job. This is like 1989....
I love your channel, thank you!
I'm happy to please. Get building, even if it is the 'ghetto' version in this video
Hi Richard,
I just built this Huntron Tracker and I must say it's brilliant.
I mostly fix 70s amplifier and I'm hoping it will save a lot of time diagnosing hard to find faults.
I was waiting for the PCB Way PCB and parts list, but I have learnt so much now figuring it out and using Veroboard.
Thanks again for sharing your knowledge. I eagerly await your new videos.
My girlfriend even loves your Car Booty videos!
All the best,
Craig.
Man! What a heady dose of genius! That was spectacular! So simply explained, yet a very powerful gadget. Thank you Sir, and stay well.
wow I used a Huntron Tracker while fault finding alarm control panels in 1981 for a now defunct manufacturer in Oldham. One of the most useful pieces of test equipment I ever used.
Thanks Richard! I really enjoy your various trouble-shooting YT's. In the early 1970's a friend gave me a rather poor photocopy of pages 23 to 26 from some sort of manual from the Mobile Radio Department General Electric Company, which described how to build this type of device using a 6.3VAC transformer and a 300 ohm & 3K ohm resistor. It was called "The Curve Tracer". The document showed the various waveforms for different components. The page numbers indicate it was part of a GE publication. I built one and still have it, somewhere in the basement. As I remember it even worked as well on a non-triggered O-scope. I really had to dig deep in my archives but I found, and scanned, the original article I didn't know about the Hameg HZ65 & found two very slightly different schematics for it on-line.
Fascinating bit of kit, many thx for sharing. Keep up the great work 😀👍
Well done Richard !
I did not remember how simple these circuits really were having used them daily back in time.
The signal relay should be optimized for a low coil current not to load the transformer.
Not a problem as any type of low power signal relay can be used.
I would not try opt for a semiconductor relay as this would complicate the circuit too much in favor of the mechanical relay.
I'd be a bit careful using the high current setting as this could damage the DUT.
In fact I suggest lowering the max current setting to about 100mA.
Yeah I did wonder about that 350mA setting - if reduced to 100mA it would mean I could use a lower wattage resistor as well. I also have a 4th position on the rotary switch to add an extra range if needed.
Did I miss the final build? I am interested in making one. Thanks and great channel.
Absolutely love this video, I know what I'm making this weekend. I've already built 3 V-I curve tracers, but being able to convert one to a 'Huntron' type will be superb. I thanks you most sincerely for sharing your knowledge.
I recently purchased a setchel-carlson triple video monitor, of which only one monitor is working. That gives me a great reason to build this! I find that machines and software work better when they are not overly complicated.
We used these units a while back when I worked at the phone company in the central office.
As electronics got more advanced thru the years, we had to stop using them because the voltage on the probs was taking out the cmos chips and some other very low voltage parts. Especially bad on incircuit testing of parts, because you didn't know where the voltage was going to ground thru other connecting parts. We just couldn't take a chance of causing more trouble then we started with.
So essentially it injecting a small signal to a component leg and referencing to ground over a small window of time ( frequency of 50-60 hz) and creating a IV curve . Cheap CCT but could probably be built with an Arduino with more functionality . Interesting project . To try an find out the problem of that amp , I would place different amplitude audio signals and measure harmonic distortion over say 4 amplitudes and 4 frequencies giving a total of 24 measurements. This may tell you were the distortion is occuring in the cycle and if it is a transitive problem or a capacitive or a DC bias . Of course I would measure DC bias voltages of transistors with zero input and you have a great opportunity as you have a working cctv.
5:32 - What you’re describing sounds very similar to what has been dubbed the “Octopus” circuit consisting of: a step down transformer; a resistor; and eight legs (two legs for the mains, two legs as the DUT probes, and two legs each to connect the X and Y channels of an oscilloscope.
25:50 - I’ve noticed that fuses in the milliamp range will have an appreciable resistance (caught me by surprise the first time I saw it).
30:50 - As I suspected. Your fuse rating is in the milliamp range!
A Magnacraft W117-4 is an IC relay that has 8 pins, is internally a reed switch, and doesn't make the clicking of a relay.
I have a Huntron Tracker = one of the best tools I have ever used for finding out about unknown components but great for matching components too. Or, as you describe, for finding faults when you have 1 working part and another that isn't working.
That's not the only one. I believe they're called reed relays
I have a Huntron comparator on my bench at work (audio repair shop) which is often helpful, but the loud clicking of the relay drives me nuts. I really need to open it up and see if I can use a quieter relay or use some foam or a different mounting just a mechanically damp the sound a little bit.
I used to have a Huntron Tracker 1005B, worked great and was very handy for troubleshooting until the display failed.
I look forward to building this.
That 32mA fuse will have that high resistance, unless the fusible element is made out of silver, then it would be a bit less
Years ago I had a problem with the stereo in my work van in that, when I played it at full volume, which I generally do as I'm a rock and metalhead, the sound would distort and cut out terribly. When I was fault-finding, I found the in-line fuse holder to be quite warm. The fuse in it was a 500mA one and when I checked its resistance it was high, I think in the tens of Ohms. I checked a new 500mA fuse in got the same reading. I replaced the fuse with a 1 Amp fuse and that cured the problem. The fuse resistance was dropping the supply voltage proportional to the square of the current being drawn, power in a resistance I SQR R and that was playing havoc with the stereo at high volume.
Most people open up their electronics to see how they’re working, but sir Richard opens up electronics to see how they’re wuuurkin… 😁 reminds me of travelling in the UK when I was a kid. Great video, thanks!
Heheheeh 'wuuuurkin'. I like it, yeah? 😂
This is SOOO good!!!
This is pretty cool. Looking forward seeing more on this sort of thing.
17:08 Who else thought that Richard had put on some of his Disco test music? 😉
Sorry Richard. I love you really and love your channel. 😆
Hahaha wait till I complete the amplifier repair video
Awesome!!! Such a useful tool (and video!)
Never heard of a Huntron Tracker before, but then again, there are so many measuring devices out there.
A Octopus curve tracer i do know, and once build one on breadboard a few years ago and forgot all about it. Time to get it back on my todo list.
20:26 Instead of using a 555 for triggering the relay, maybe a flashing light (turn signal) relay of a car can be used. When all flashing lights (light bulbs) of a car are okay, the flashing rate is arround 1Hz per second, but when there is less current draw through the flashing light relay due a defective light bulb(s) , the flashing rate goes to 2 or 3Hz per second and the driver will notice the quicker clicking inside the car.
These frequencies 1Hz to 3Hz are ideal for our measuring purposes here.
Yeah that should do the job just fine. This project really lends itself to using commonly found salvaged parts.
As usual the video and topic is fascinating. I’m starting to find myself browsing through the comments and respect and admire all the different suggestions, explanations, additional knowledge. Every videos comment section has really helped give me a spark that I didn’t know was there. I have an itch that wants to be scratched 😂. Thank you Richard, and thanks to everyone from the professional to the hobbyists for asking and answering questions and providing insight at many levels. ✊
huntron still around you know. price is over the budget of most of us at around 6K. and if you think that is expensive take a look at ABI electronics modules very crazy prices but crazy capable, it seems.
I have a Hameg Analogue oscilloscope. I believe it was one of their last Analogue scopes. That oscilloscope has the component tester built in. Good memories to hear about the Huntron.
Like it ... but that clicking like a car indicator would drive me nuts. I use mine with a USB scope ... put single probe to first test point, hit spacebar to freeze the component shape ... move the same probe to the 2nd test point to be compared, hit spacebar again and you get an instant comparison in silence ... (can also save screen captures of component shapes etc.) ... still an invaluable tool at times ... :)
Richard that was a really interesting video, it really got me thinking about your home built add-on device you made and how it could be used to fix a stereo audio amplifier. What about injecting a 1 kHz signal into input of each channel and then signal tracing the amplifier sections with the switching device and the oscilloscope, comparing waveform in each channel at the same time. Do you think that would help in finding the distortion in the amplifier?
by the way Hameg built in the component tester into their range of oscilloscopes.
When I was in the Air Force, we always used a 1 Khz tone to trouble shoot our radio equipment. We injected at a certain db, and then used test points through the system to look for loss or a change in frequency from the usual norms.
Sir, I regret to infrom you that blue leds have indeed been around for 30 years. ;) Awesome channel, thanks for your work!
I definitely want to build one.
Nothing wrong with the relay, at least you know it's working.
The timing issue coming from the supply voltage to the 555 timer varying when larger current is drawn. A regulated suppl y to 555 should alleviate this.
I was thinking the same thing when I was watching. 78L05 or something similar.
Built one of these,must be 30+ years ago,still use it today,such a simple device,be carefull what you test with it,as it can damage sensitive parts,but if your a quilified electronics engineer you should have no probs. understanding its few limitations.
This type of tester was used quite frequently years ago. Now, however, the current across the probes might be too much for many sensitive solid state devices. Keeping the current to around 3 ma and using a 4066 cmos solid state switch may be an idea.
Back in the "dark ages" around 1972 while I was in the Navy, I was exposed to a device called the "OCTOPUS" that was a single channel IN CIRCUIT component checker. Same device concept LESS moving parts. (still needed an 'O' scope) A JEWEL to use !
May be an odd thing to say, but modern semiconductors are IMHO more resilient than the old stuff. When was the last time you were heatsinking component leads with pliers just to solder a transformer or a diode down without damaging it? Low voltage cmos usually has lower impedances and will shunt a higher voltage no problem. I agree though that what this could use is a bipolar current source and adjustable compliance limit. Sure it would complicate things more, but would cost about the same as it’d use common parts.
Well engineered Octopus mod. An observation / suggestion. The bridge (power for the relay etc) is now effectively across the X/Y and that and the relay / LED load will affect things. Perhaps use a low power LED and an analogue switch / multiplexer or 2 x FETs instead of the relay. A pot or a selector switch instead of the preset so you can set the voltage (low for micros, high for zeners etc) and some sort of voltage display (even if only a simple LED bargraph). Did something similar to my Octopus (no marine life was hurt) many moons ago.
My transformer has two independent 6V windings si it is not exactly in parallel but does load the same transformer primary which effects the voltage slightly on both secondaries. My take on this is to use a (working) salvaged PCB out of a 5V or 12V switch mode power adapter to power the relay switcher. NE555 works with Vcc from 4.5V to 16V. Then get a single 0-6V linear transformer for the tracker circuit. Both are actually isolated from each other by the relay, and have different grounds. As the linear transformer is the single most expensive part, building it as just described is the cheapest option and also prevents the relay current affecting the display slightly.
@@LearnElectronicsRepair Ah, the 'schematic' (38:39) did seem to show the AC input to the bridge (powering the relay) being across the same secondary that is providing the X / Y. Yes, it would be better to use a transformer with two secondaries or a separate PSU / adaptor to power the relay part. You can make you own ss relay using MOSFET's (to avoid the ludicrous leakage and high minimum current of conventional ss relays), you already know a lot about FET circuits.
Very interesting explicated. Thanks!
Thanks for the video. I want one now
DiodeGoneWild built up something very similar to this. I think he used an AC wall wart that is fairly common in Europe; these things are mostly unknown to Seppos like me.
As for the switching, you said it's low voltage and low current, yeah? A pair of optocouplers would be an ideal substitute for the transistor and relay.
EDIT: Since you had the three RCA jacks, you could have dispensed with the switch, all together. ("You could have dispensed with the switch.") Select current by moving the test lead across the three jacks, just as you would select amps or milliamps on a moldymeder. And I would have used banana jacks rather than RCA for everything except the scope output; I'm guessing none of your test leads are shielded to the tip.
I think the relay option is good because a relay contract won't change the characteristics of the test path. A CD4016 or CD4066 might add some unexpected artifacts.
At my job we use also the huntron; i thought it was a complex piece of equipment :) I certainly will make one my own
Huntron tracker technique was mostly use throughout my electronic repairs. I'm more visual than looking at numbers.
i just finished building it and it works greats.just like the original!
Perfect for the device building.
There is one that I had my workgroup at my current company purchase, however... Just want to add a disclaimer that I'm NOT sponsored or compensated in any way by the company who makes them, nor am I expressing nor implying endorsement. With that mentioned, a company called "uCore Electronics" makes several versions with various capabilities. They have a TH-cam channel and their own website where they can be checked out.
Speaking on personal experience, V-I testers have worked quite well when it comes to discrete component testing, though may not quite be useful when it comes to LSI IC's. For my own personal repair business, I have a DIY version that uses a combination of my Oscope in X-Y mode, a function generator with variable sine wave outputs, and a power supply. The Mr. Carlson's Lab TH-cam channel has a version that designed that he makes available through his Patreon subscription.
Even though commercial versions have limited availability today, there's lots of DIY versions that can be found looking online.
Just my .02 cents.
That's fine mate. This version was intended to be possibly the cheapest possible way to build this. I did actually mention using a sine wave generator rather than a liner transformer during the video. When I used the Huntron Tracker in the 80s we were definitely using it to diagnose LSI ICs - basically by the method of comparing a good board and a bad board looking for any differences.
Very Interesting video. I used to use. Huntron many years ago, and was horrified by the prices they command, even for a very old model. I was hoping to find something that used one of the cheap Chinese LCD scope kits and the tracker adaptions as a modern low cost replacement. In your video, another enhancement you could add, is to have an option to switch much more quickly, and then provide X and Y offsets to both channels, so you can display the waveforms alongside each other.
Yes that would work too and shouldn't be too difficult to implement. I'm not sure it would make the device more useful but it would be fun to try.
The r&s HMO1002 scope has a single channel tracker built in. Never used it personally but it was in the users manual.
Great video as usual, i used an AC output Power Brick for mine! It would be nice if there was an image store of components that you could compair to
20:50 - A normal fuse with a very low rating will have a notably higher than expected resistance. It might be of interest to see the voltage drop across that fuse.
It’s ironic that I just viewed a video from the Play with Junk channel on this very subject of the curve tracer/tracker 😮 …
You could add one of these cheap little 20€ scopes as a screen, then you have the complete tester in one box.
Hi I think I know a circuit that can be adapted to work for this device . It uses a 555 timer a cmos Dual D flip flop and a cmos quad lateral switch and can run on 9 volt battery I can send you the schematic if your interested.
Please send it to me.
I would be interested also
I'm very interested
Please send it.
In the U.S. these are generically called "Octopus Testers" The earliest mention of these I have found was from a Naval training document of the early 1960's.
Thank you - video title updated again to help more people find this video 😁
Thank you, Teacher.
i use a huntron 2000 quite often at work and was looking for something cheaper to use at home. perfect timing. was this finished id like to get one.
I think for this to work on modern logic, that don't like -ve voltages, it would be necessary to apply AC 0V pk to 3.3V pk and also AC 0V pk to 5V pk.
I think the 1M pot goes between the RED lead and GND.
It's generically known as a curve tracer. That will find you a lot of schematics and detailed explanation of how it works.
Video Title changed to include that name, but I can tell you no one called this a curve tracer when they were made, that name must have been invented later. Anyway I hope you like this video
@@LearnElectronicsRepair A curve tracer was a very old piece of test equipment, from the 50s and 60s... Back then it was the only tool available to characterise components, and using one was a highly skilled task, interpreting the shape of the curve and taking measurements from it. These days we have component testers and dmms that do all the hard work for us. They were already largely obsolete by the 70s/80s, which I guess is why you'd not heard the term. It is the sort of thing that gets rediscovered by successive generations as it is occasionally useful to see a visual representation of how a component behaves rather than just the numbers. The Huntron was just one such example, targeted specifically at diagnostics. I recall seeing adverts for it in magazines 'back in the day'. It was one of the many tools that I couldn't afford, that I thought would help me fix stuff. The reality, as you've just demonstrated is that it's knowledge that counts. With enough knowledge you can just build the tools.
@@LearnElectronicsRepair yeah I thought "this is a dual curve tracer". The MAC97A6,412 triac does about 600ma, maybe you want a beefier package. dunno.
I have a (broken) 1985 Crotech 3132 oscilloscope with built in component tester !
What a nice device! I must build one too, thank you :-)
Is there a PCB and components kit available for this project? I do not have very much in the way of "scrap" parts and would really like to just build from scratch with new components.
G'day Richard, all your videos are very well explained for a layman like me. Cudos to your abilities. Is there an actual build list or kit available for this product? Keep up the great work
Great device, but I'd look at much smaller relays to start, that clicking sound would drive me absolutely batty in short order.. definitely a cool tool though!
A little note about the oscilloscope. You have an analog one, which is great. But many modern digital scopes exhibit peculiar behaviors, if used in X-Y mode. That as a warning...
I have 3 scopes - two analog and one digital. This would work with any scope that has a functioning X-Y mode. If the designers of digital scopes can't make them properly then I don't see what I can do about that 😋
Works on anything with XY mode ... :)
If you get a new ociliscope it is now biult in and will do the XY.
I've noticed something with THIS channel, mostly.
First, I have Business internet, high speed, solid, no glitching.
I watch a lot of videos and movies (netflix, etc). Never an issue.
But with THIS channel, several of the videos will hesitate with "spinny thing" and worse if I click forward in the video.
Other vids don't do that.
Hmmmmm
Shit like this makes this channel even more enjoyable. Thank You.
you are welcome
Heya that a nice tool wen your working on amplifiers wen you have only 1 channel working
Commenting with this video having 555 likes. Seemed like a good opportunity to help out with a comment. I like the device!
Oh, and I forgot to mention, I have built an octopus made to work with my AWG and it worked fine. It might not work with generators not capable of sourcing the current, or enough of a voltage swing, but mine did the trick in a time of need.
superb looking tracker :) any updated videos on this ? :)
That's neat, I like that.
Will this work on a digital oscilloscope? ...Or is a CRT just better for this?. ........Thank you for helping with the learning curve...
You need any oscilloscope with two inputs that works in (X-Y) mode.
very nice unit, thinking of making one, I noted that the trim pot goes to the black probe (schematic 30:00) and not to the other side of the transformer(your drawing 37:55) it don't seem to make a difference as the circuit works
Yeah I think that is because the value of the resistor on the switch is low in relation to the value of the 1M pot - but it should be made the correct way (at 30:00 as you mention) I will fix this when I order the PCBs from PCBWay
Hi Richard, any chance of a simple diagram of how you implemented the 555 IC, the link you provided seems to show a lot more components than you seem to have used. Thank you for sharing your knowledge with us, Regards form South Africa.
You could call your version the Ham'n'Egg.
solidstate relay will work too
Thank you very much for this informative video about making the "Huntron El Cheapo Clone (HECC)". What if i want to test low voltage ic's like in tv's or in video card's? Would this device damage the circuit or is can simply lower the voltage and reduce further the current? It's maybe an option to extend the usefullness of your device. I'll hope you have a solution and are willing it to share. Have a nice day. Greetings Henk.
It works on the lowest range at 3.5mA and I doubt it would damage anything, but you could easily modify it by changing the resistor values, maybe reduce the highest current range to 100mA as some other have mentioned and use the spare switch position to add a 1mA range? Actually the one I built here uses a 6V transformer instead of 8.2V so you can probably de-rate all the specified test current ranges by about 20%
Hi Richard. Thanks for this video bro! :) If i might ask for your expert advice/cooment. How common are circuits that are identical for comparison in the same device? What other uses and what other types of regular device can this assist with? Also. Can you help us viewers with discounting a benchtop 2/4 channel high frequency O/scope? there's no way the premiums charged for decent spec by scope manufacturers like keysight etc are anywhere near affordable. especially for those of us trying to break the threshold into advancing repair skills on state /disability benefits.
When I was using the Huntron Tracker in the 80s it was really to look for differences between a good and bad identical PCB. That is where these really excel. I'l looking to review some oscilloscopes in the $70-$100 range when I get chance as this seems to be a sweet spot between price and performance.
@@LearnElectronicsRepair Wow I gave Rob some good advice about scopes with only a link to open source software on Github ... and you have removed it?
@@johnnybravo505 Many channels on YT automatically and silently delete comments with URLs. Sometimes Wikipedia and YT links pass through but not always.
What is a handy way to pass on information is quoted search string like "github oscilloscope" and then the user gets to filter the results instead of the channel owner having to hope that the link contents do not change to oppose the narrative.
Great Circuit
If an HZ65 can't be found, could you recommend an alternative option to use with my scope ? Great video !
Recently got a huntron tracker for 70 dollars felt very lucky
You were definitely lucky!! Does it work?
@@LearnElectronicsRepair haven played with it much but everything seems to be good
Nice Simple Device - To cut cost why not use a rechargeable £1 1 x 18650 5Volt DC power Bank - No need for 2 x Rectifiers, cutting even more costs. plus if like me you have 13 amp sockets with built in USB 2Amp chargers. Making the Tracer mobile or bench.
Yes - my best suggestion is use a (working) PCB from a SMPS power adapter - 5V or 12V to power the relay switcher (NE555 works form 4.5V -16V, just select a relay with a suitable coil voltage) then use a liner transformer for the tracker. Electrically, the two circuits are isolated, by the relay. This would work better and be even cheaper than my version if can salvage an old power adapter.
@@LearnElectronicsRepair The 1 x 18650 power bank, Comes with an inbuilt 3V7/4V2 to 5V DC Booster - Charger IC that runs at about 4Khz ( I think) & your mains Transformer is 50Hz - For the X Y timing Cycle So with a 2 transistor oscillator and some Caps Filtering we could make a 50 HZ Sign wave. Also use another 2 transistor Oscillator to run at about 1 or 2 HZ one probe to 1 transistor collector the other probe to the second transistor collector No need for a relay - Hartley oscillators - A job for the BC109s Or 2n2222s - What do you think?
Hi Richard, wondering if there is a way to order just 1 PCB from PCBWay rather than 5? I just want 1 board, but it defaults to 5 with no option that I can find to lower that pre-set quantity. Also, how can I order the ruler? It says the ruler requires 50 beans (have no idea what those are or how to gain "bean credit"). Cannot seem to just be able to pay for it normally. Maybe their process has changed since you posted this video over a year ago? By the way, Heathkit made an instrument called the Component Tracer (Heath Model 2232) which was essentially a Huntron Tracker clone for a lot less cost. It allows two separate test probes to be used with A/B/AB sampling capability and two switch-selectable test voltages (5V or 50V). In the AB mode you can super-impose the images in real time rather than dealing with the switching issues and associated noise glitches. The traces are distinguished by one being solid and the other being a dotted line. These devices are available every so often on eBay and often run less than $100.
Could keep it old school and replace the relay with a bistable multivibrator circuit switching a couple of transistors or mosfets
That you could do replace the NE555 with a bistable multivibrator - in fact I comment before I dismantle it that I can't remember if I used a 555 time or transistor oscillator when i built it.
Nice project
This is my specialty…. So feel free to ask any questions I’ll help however I can
I have a small business and laboratory specializing in component level troubleshooting and repair/calibration of industrial equipment. I specialize in test equipment and other metrology related stuff.
I also have a collection of curve tracers, short finders, Huntron trackers, polar “tone-ohm” devices…..and dozens of other troubleshooting type devices.
Some of them are built from old DIY schematics from retired HP engineers and elsewhere. Some really interesting stuff
So If anyone has any questions about that type of stuff….. feel free to drop a comment or question down below. Lot of experience looking at that type of stuff
Thank you for your kind offer. So what did you think of my El Cheapo version of the tracker?
Is there any way In which you could upload the schematics of those old hp test equipment..for everyone to see?
So here's a question then; are there any currently manufactured devices that make it easy to measure resistors for noise, Johnson or thermal noise? I took a quick look online and didn't see any such product, and the only time I ever remember reading about it was a do-it-yourself article from nuts and volts magazine a few years ago.
Trying to order these from PCBWay but says subject to audit... What's up with that?
Nice video, thanks :)
Thank you for teaching us.
Can the the Huntron tracker be used on surface mount boards, or will it damage them?
Yes it may. The low voltage components used these days are susceptible to even the electrostatic charge on your skin.
36:24 Hmm - my instincts were bugging me about the resistors being on the black wire and not the red wire; seemed like touching the red wire to the wrong thing could short the transformer. Upon further inspection, though, the bottom side of the transformer isn't "ground", it's just sorta-floating. Is that ok, to have the transformer in such a design not have a fixed reference point?
Is the Scope display flicker difference;... not the finite time the relay contact are in mid position (ie: no man's land) neither connected to 1 or the other...
That is what I think causes the flicker, the relay switching delay
Have you developed a board/kit for this?
really looking forward to this project
could you replace the relay with a flip flop circuit ??
This is what I was thinking and hope some guys here know the answer
@@LearnElectronicsRepair im just a noob so havent got the proper solution. all american 5 radio made a simple flip flop circuit, maybe you could adapt it to your needs.
@@garygranato9164 It needs some electronic device which can switch a 50Hz AC signal on and off, conducting 3.5mA - 350mA depending on the range switch, without distorting the AC sine wave. This is beyond my expertise too - I'm a circuit fixer come part time bodger rather than a circuit designer 😉 IMHO the relay works for that purpose just fine until someone convinces me it is cheaper/works better some other way
Or perhaps a solid state relay instead so it doesnt sound like an australian pedestrian crossing when in use.
@@LearnElectronicsRepair You want a triac. Search for 'SSR circuit', they tend to include optical isolation which you don't need but I'm sure you can figure out the details now you know it's a triac you need.
I clicked on the PCBWay ruler link, it gave me error : “ Safari can’t link to the server, because it could not establish a secure link to the server”. ☹️
Fixed
www.pcbway.com/project/gifts_detail/PCBWay_PCB_Ruler.html
Would you be able to send me the schematic? Love this project. Currently working on many of the same type switching power supplies. I have one working and the other 20 do not work.
Curious as a home Hobby repair guy with this work with modern equipment?
👏🏻👏🏻👏🏻
I see 1 Hameg HZ65 ( Zed) for 127 quid on eBay, great project you have there and I certainly learnt something today, will you film yourself creating the PCB ?...cheers.
Yes definitely. I will pass this over to Carlos at Retro Upgrade who is much better than me at PCB design and we will publish a part 2 video (most likely to be on this channel but do check out Retro Upgrade too).
th-cam.com/users/RetroUpgrade
We'll get some prototype PCB ordered (free thanks to the PCBWay sponsorship deal) and once tested this will be uploaded as a PCBWay shared project for anyone to order. This process will likely take 6-8 weeks, in the meantime feel free to build or improve the 'ghetto version' featured on this video. None of the components are critical so you can just experiment with the design. 🙂
Anyone wanting to build your own sponsored projects with PCBWay, come over to LER discord or email me electronicanaria@outlook.com and I will help facilitate that for you 😉
Learn Electronics Repair is now on Discord! Come and join the fun, it's free.
discord.gg/vam6YC8vwU
@@LearnElectronicsRepair Great stuff ! I went to join Discord but was told 'unable to accept invite' dont know much about Discord so will try later...cheers.
@@andymouse Really!!! The discord is open to everyone, if you still have problems please email me elecronicanaria@outlook.com and I will try to help you