In case you're still wondering about all those "extra" holes in the keyboard PCB (50:00), they're required in order to do the gold plating of the membrane contacts. All of the traces are initially shorted together so that there is electrical continuity during the plating process, after which the holes are drilled in order to isolate the individual tracks.
Yes, quite enjoyable indeed. Whould've laughed my a** off if Dave epoxied that hybrid back together and added a few drops of conductive paint, just because. But eh, not worth it.
That feel when you have so many brand new scopes that you showcase three new scopes for no reason while troubleshoting a different, newly bought, scope. You could say that Dave (puts on glasses) is in scope acquisition mode. YEEEEEEAAAAAHH!!
You knew. You showed us everything. How could you do a proper instructional if you just jumped on the problem? You took us on the journey of how this scope is built. Thank You. My eyes have never been more open. You are an awesome teacher. Isn't "dumpster diving" so rewarding? I know this scope was not a dumpster find. It is amazing what people throw away. Oh, well. Good for us! :-)
It's always a good feeling to track a fault down to a physical problem like that. I remember when i was a kid in school and the Pioneer car stereo in my first car crapped out, so I took it apart and traced the fault to a crack in the PCB, repaired the affected traces, and hey presto, working stereo again! I was pretty pleased. PS: full 1080p here no issues.
This was the most exciting hour of video I've seen this week! Seriously, the excitement of finding the crack in the PCB was felt in my home also! Great demonstration of troubleshooting techniques
As I've mentioned previously, I studied electrical engineering from 1993-1999, and I haven't touched an oscilloscope since then. That particular model brings back memories of school, and how I absolutely despised my circuits classes. It took almost 20 years and TH-cam to make me like electronics again, but I won't be quitting my day job writing embedded software. Electronics is strictly a fun hobby, not to to be done in school or professionally.
Glad to see a repair. Don't see them too often. They are the main videos I like to watch. Maybe the scope was dropped - that could be the reason the front panel had a broken piece on it! Good video!
Yeah lol - as soon as I saw that cracked lid - the answer was there at the start. But it was worth it for the educational stuff covered from looking at other possible causes. We all learn from mistakes - even other peoples ;)
+GadgetUK164 My thought too - fresh-looking mechanical damage outside and a fault ticket usually means mechanical damage inside too. BTW did anyone else go back to the first clear shot of the cracked PCB and wonder why the lighting/angle was such that you couldn't see the damage? Could Dave have spotted it very early on, decided that would lead to too short a video and so went off around the houses?
I will totally try to at least open this hybrid ceramic. It's broken anyway, so maybe heat it up with airgun, look for insides, maybe regular glue + conductive glue can make it sorta work(maybe you can even solder those traces together with solderpaste and reflow). Give it a try, Dave!
Good fun Dave, thanks. I think that you found that fairly quickly. Good detective work. Though it's always an idea to flex or apply pressure to a board in various places with a suitable prodder whilst twiddling unresponsive knobs, or whatever. Some boards you just know will be trouble. Any that get user strain, or those that have heavy components or are flexy....or worst of all a flexy board with a heavy item getting user strain - with crappy solder (all 80s 90s TV sets).
Just wanted to say a big thanks for your vids that given me the confidence to fix the EMI caps on the 2467B that I got just as the old Rifa's let go. Not a big deal to you guys probably, but I was chuffed that I managed to fix it. Beauty, as you so rightly say!
Thoroughly enjoyed. Come on though Dave a little grinding with a Dremel on that ceramic package and I am sure you could get a bodge wire to bridge it over the crack after repairing the substrate with super glue! Give it a go!
I recently aquired an Agilent 54615B 500MHz like this one (only 1GS/s though) and I've got to admit... I love the thing. I use it more than any of the others, lately. It was in much better condition than the one in the video and only needed a little cleaning up. It has the top mounted probe pouch, which still looks brand new, and the scope works like a dream. It doesn't appear to have been used much... none of the usual worn down labels and stuff. I got it so cheap, I'm afraid that if I mentioned the price I'd be arrested for theft. Best price on a new Hantek 50MHz scope, on feeBay, is quite a bit higher. Great video! I enjoyed watching!
Really enjoyed that Dave. Nothing quite like seeing the process from start to successful finish. Would make a great scope for anyone now- even if its left as single channel. Cheers!
Dave, You got me super interested with this repair, old school cpu address lines being used to strobe the controls, very similar to the old keyboard reading method in 8 bit computers. I thought about the 74LS2XX bus transcevers as well, old school :-D
Seeing that purple hybrid gave me cold memories (Those often drift/fail in 3458A DMMs, causing a replacement of ADC board for over a grand USD). No peaking inside cracked hybrid? Could be interesting under Tagano microscope ;)
Excellent example of how troubleshooting can change your symptoms and thoroughly confuse the repairman. As an electronics technician I have seen more than my share.
At 32:20 I was wondering about dry or cracked S.M.T. solder joints. I wanted to reach through the screen and push on some chips to find that dry joint. High tin solder is suspect.
Great work Dave , as a rule for repairing I use a scope probe and push PCBs down with light pressure to see if the symptoms show any sign of dependency . I then hook onto a device that is soldered with the hook and pull board upward gently ..looking for the same . I can't tell you how many times I found stressed solder joints or cracks in board cracks normally suggest impact from my experience. It also is apparent that screws , connectors , chips with pin mounts are all mechanical areas of Faure for older boards especially if they have had some impact. Nice 👍 work
I had decided to study semiconductor devices lecture but than I saw this video's notification and then...... a whole hour just passed :D Thanks Dave, you are such an inspiration for me :D
Exactly the same thing happend to the HP54600B I was transporting in the car. Front panel got a bump in the car and put a hairline fracture in the front panel pcb. A few links later and Bobby Dazzler! Love these era HP scopes.
Repair/troubleshoot vids are my fave.Thumbs up or sure! Great job, Dave! That was tough unit, especially given all the DIFFERENT things messed up with it. Try to find more stuff to fix.
A late feedback - but thank you for this repair - I am sitting with two of these family scopes with button and rotary issues - I got both really cheap from ebay - intending to repair and this video was really intructive, exposing the rabbit holes... :-) thank you Dave!
Not long time ago I hand-soldered a small batch of 2 layer boards, few of which didn't work during test. After some checking, replacing few ICs I found that some vias were broken straight from manufacturer.
In my experience you can find cracks reasonably easy with one or two layer boards (sometimes up to four layer depending how the middle layers are routed) by holding the board against the sun at an angle. The light traveling through the board will be blocked by the crack, producing a darker line often at an odd angle to the traces. A lamp that produces reasonably parallel light will work also.
"Always look out for any dodgy tantalums." - Recently had one tantalum cap explode on me and found another that had split in half some unknown time ago. Both in Williams pinball machine sound boards. Replaced with MLCC but haven't tried thumping them :-)
Dave, don't know if it's been mentioned, but to repair the hyprid module - tin the 3 or so broken tracks with silver solder (lead-free) don't use lead based or you'll strip the tracks clean off the ceramic, flux it up good and proper and heat the smaller broken side up with your hot air gun while pushing the two halfs together - you should have rejoined the brroken tracks at this point almost seamless, once your sure - super glue the crack along the top. Should be working after that.
Ahh didn't spot that. chances are slim then - still might be worth giving the above technique a shot but it'll be trickier. can't break it anymore than it already is i suppose
dom291 Old Tek scopes came with a reel of silver solder inside the case. This was because it used ceramic tag strips that had to be soldered with silver solder.
I've had this "InEr" on my new BM789 after spraying the smallest amount of electronics contact-ol (like deoxyt) into the probe sockets. After opening the unit I cleaned the pcb around the probe sockets and it fixed it. Seems that the probe detection cct is very sensitive. So, you could try to clean up the pcb of any residue and see how it goes.👍🏻
we have this model in our local maker space have repared two tines with out some dokumention, first time some r27 has getting larger in the power supply, found the tip in some forum
I've been lucky powering it up and if no smoke, running a temperature sensor over the board.. in most cases, it's either cold or too hot. Contact cleaner on the pots really cleans-up the signal, connectors might be next. I wiggle around all the controls to see if any of the contacts are dirty. Vacuum it out, pull off the knobs, spray a little bathroom cleaner (foam) on it, wipe it off, and replace the knobs. This is coming from a technician who has been on the track a long time.
I use to work in the lab at LM ericsson, making phone systems a few years back. When I start working there the lab looks like a cartoon lab with stuff just everywhere... So I started making identical work stations so everyone could work at the same time. So I go down in the cellar and looked and there was those HP around everywhere. Was like 20 of them around. I just needed like 6 or 7 of them. Pretty much every single one of them was different. They all looked identical. But was different specs and functionality.
I worked with lots of large hybrids, but I never saw a pogo socket like that: Ours were always PGAs into ZIF sockets. But we weren't pushing GHz signals around.
I have the HP 54602B (150Mhz) which is pretty similar to this one. *great* scope. The pass/fail mask feature is pretty neat. Purchased a new battery backed ram module a year or so ago, i'm sure the original one will die one of these days.
Actually the erratic rotary encoders are easier to fix than you think. It happens because they have been sitting for too long unused. Just dial them in each direction 100+ times and you'll see it improve gradually. I got lazy and grabbed the encoder shaft with power tool chuck and it works brilliantly. I repaired two units in the same 54600 series with broken keypad PCB like a decade before. It happens not because of the manufacturing quality, but somebody who opened up the keypad later (attempting a repair) forgot to slide the PCB under the hooks first before putting the screws on, inevitably bending the PCB until it cracks. Now I have so many of these units that I just wouldn't bother saving one of those cracked front panel keypads.
Would have loved to see how you "fixed" the broken lines and strengthen the board. Had similar issue with mine, removed green coating and joined the line with a thin wire but always feel it would break again overtime without putting a real reinforcement on the board... Anyways, awesome content as usual, keep it coming!
Old HP54600 series' front keyboard usually crack not from users being rough, but somebody was in the front panel keypad before but didn't know better to slide the board under the retainer but instead they just forced the board above the retainer clips with screws. The repair guy thought they got away with not RTFM and over time the board fractured from the unnecessary stress from the retainer
I have a 54601A, 100MHz, 4 channels that I was lucky to get on a local junkyard for $70. It was being sold as non functional, but I found before buying that it was just the bright control that was at the minimum... It doesn't have all good stuff of modern osciloscopes but is good enough for my hobby activities.
When it's obviously taken a good bounce off the floor, first thing to assume is a cracked PCB somewhere. If it landed on the front panel, you'd have stress points where the pots took the force of the impact.
Bloody relieved that you fixed it, always disappointing when you try everything and you can't get it working, or you Get it partly working. That's not a criticism of yourself, but there's a tension as to if you can fix it or not :)
How about testing a few of these DIY oscilloscope kits you can buy on ebay and build yourself, and see if those are good enough for your beginner DIY hobbyist? They're very cheap, 30-40 bucks so well within the range for early beginners. Search for DSO138 or DSO150 or similar, made by JY Tech. Could be a great start for beginners who are on a budget and can't afford a proper oscilloscope if they're useable for basic situations. :)
I've just finished debugging one of those that my brother built for fun. it was his first solder project and he was tearing his hair out as to why it did not work. long story short: the microcontroller is soldered on by JY Tech and 5 of the pins were loose or intermittent... the poor guy almost gave up and brought it over as last resort. working now and zero percent his fault..
Well, it is chinese so bad soldering does happen I suppose... :) Might not be the best kit for a first kit building project, but it's a great and cheap way to add an oscilloscope to the toolbox, and a very portable one at that. :)
Saving money and getting a cheap oscilloscope kit like the DSO138 or 150 may be very valid in some countries as well. As an example, in my country, Norway, you have to pay 8-900 US dollars for an HP 54603B used... Insane price, and nobody in their right mind would pay that, but that's the price in Norway.. Ordering internationally is expensive as these big classic CRT oscilloscopes are heavy and expensive to ship... Where I live now, the Philippines, I can't even find a decent used oscilloscope. So one of these kits would be a great way to get started in a situation like that... :)
??? How did you replace the traces? Mod wire to good traces?? Foil copper over broken traces soldered into place and solder masked?? Epoxy resin or super glue on the crack? How did you decide which methods to use??? ALSO ASKING ANYONE WHO IS EXPERIENCED IN ELECTRONIC REPAIR TOO!!
Usually when it's a section of buttons/dials not working in a keyboard in general (even a good old computer keyboard that I'm typing this comment on), it's almost always a physical crack/disconnect in the lines. I'm surprised Dave chased it down to the active components before taking the front panel keyboard out for an inspection.
Did you do anything to stop the PCB crack from propagating further? I would consider drilling relief holes at the ends and/or reinforcing with epoxy and fiberglass fabric. I also would probably epoxy that hybrid end back on and splice the traces until the replacement arrived.
In case you're still wondering about all those "extra" holes in the keyboard PCB (50:00), they're required in order to do the gold plating of the membrane contacts. All of the traces are initially shorted together so that there is electrical continuity during the plating process, after which the holes are drilled in order to isolate the individual tracks.
^^ Needs more upvotes. ^^
@@0x8badf00d agreed, it got mine
instablaster...
TIL
Nothing better than a 1 hour repair vid.......... brilliant.
Glad you liked it.
Yes, quite enjoyable indeed. Whould've laughed my a** off if Dave epoxied that hybrid back together and added a few drops of conductive paint, just because. But eh, not worth it.
28:03 My new ringtone for my phone and I am not even joking.
Ahaha someone beat me to it, I thought I was the only person morbid enough to think about this lol. XD
He sounds like R2D2 does when he gets zapped by something.
The Signal Path Z
th-cam.com/video/GlM6PE2kKVY/w-d-xo.html > Another one found haa haa luv the electric shocks - touchy
I thought you were going to use this 58:45
That feel when you have so many brand new scopes that you showcase three new scopes for no reason while troubleshoting a different, newly bought, scope. You could say that Dave (puts on glasses) is in scope acquisition mode. YEEEEEEAAAAAHH!!
Well played. That actually got a legit LOL from me.
Maybe he's into marketing mode with brymen and siglent stuff..
Nothing better than a 1 hour repair at 6:20 am! Good morning everyone!
Yeah, what a bobby dazzler!
6months after, and is 6:20 am
4 years later and it's 6:15 am
it is 12am (UTC+8)
Thoroughly enjoyed the whole hour, thanks Dave :)
Thanks.
You knew. You showed us everything. How could you do a proper instructional if you just jumped on the problem? You took us on the journey of how this scope is built. Thank You. My eyes have never been more open. You are an awesome teacher. Isn't "dumpster diving" so rewarding? I know this scope was not a dumpster find. It is amazing what people throw away. Oh, well. Good for us! :-)
It's always a good feeling to track a fault down to a physical problem like that. I remember when i was a kid in school and the Pioneer car stereo in my first car crapped out, so I took it apart and traced the fault to a crack in the PCB, repaired the affected traces, and hey presto, working stereo again! I was pretty pleased. PS: full 1080p here no issues.
This was the most exciting hour of video I've seen this week! Seriously, the excitement of finding the crack in the PCB was felt in my home also!
Great demonstration of troubleshooting techniques
Good job Dave! Nothing is better than your repair. That is the best practice for all of us.
As I've mentioned previously, I studied electrical engineering from 1993-1999, and I haven't touched an oscilloscope since then. That particular model brings back memories of school, and how I absolutely despised my circuits classes. It took almost 20 years and TH-cam to make me like electronics again, but I won't be quitting my day job writing embedded software. Electronics is strictly a fun hobby, not to to be done in school or professionally.
Glad to see a repair. Don't see them too often. They are the main videos I like to watch. Maybe the scope was dropped - that could be the reason the front panel had a broken piece on it! Good video!
Fascinating video. Love these long repair videos. Better than any TV drama!!
Thats our Dave - playing a few hours with scopes and signals before considering to trace that crusty PCB. ;-)
Yeah lol - as soon as I saw that cracked lid - the answer was there at the start. But it was worth it for the educational stuff covered from looking at other possible causes. We all learn from mistakes - even other peoples ;)
good shout.
+GadgetUK164 My thought too - fresh-looking mechanical damage outside and a fault ticket usually means mechanical damage inside too.
BTW did anyone else go back to the first clear shot of the cracked PCB and wonder why the lighting/angle was such that you couldn't see the damage? Could Dave have spotted it very early on, decided that would lead to too short a video and so went off around the houses?
Wow, great repair, and the display on that Siglent scope is pretty beautiful for an entry-level model.
Used an HP54161B long ago bought it from the company once they cleared all their hardware. A very nice piece of equipment.
I will totally try to at least open this hybrid ceramic. It's broken anyway, so maybe heat it up with airgun, look for insides, maybe regular glue + conductive glue can make it sorta work(maybe you can even solder those traces together with solderpaste and reflow). Give it a try, Dave!
This is exactly the kind of content I LOVE to see on your channel! I enjoyed every minute. Thank you, Dave! Please keep on doing this great work.
Your repair vids are great. Well paced and i only fell asleep once. Keep up the good work.
Good fun Dave, thanks. I think that you found that fairly quickly. Good detective work. Though it's always an idea to flex or apply pressure to a board in various places with a suitable prodder whilst twiddling unresponsive knobs, or whatever. Some boards you just know will be trouble. Any that get user strain, or those that have heavy components or are flexy....or worst of all a flexy board with a heavy item getting user strain - with crappy solder (all 80s 90s TV sets).
This is great. I scored one of these at my college when they cleaned out surplus equipment. It's what got me into electronics.
Nice to see a 68000 still in action once in a while.
Good repair, Dave! Cheers!
Just wanted to say a big thanks for your vids that given me the confidence to fix the EMI caps on the 2467B that I got just as the old Rifa's let go. Not a big deal to you guys probably, but I was chuffed that I managed to fix it. Beauty, as you so rightly say!
None of this Agilent rubbish! >Agilent logo on the handle..
i was just about to say
0:05
Scrolled down if someone noticed it... sure enough. :D
Abel Lujan >came here to comment that< >am too late
This was awesome to watch! Just blown away that the CRT has survived whatever shock went through the unit when it was dropped...
For the crack on the PCB that was not a drop, that seems to be a punch on the rotaries, may be was having a bad day? 😂
Thoroughly enjoyed.
Come on though Dave a little grinding with a Dremel on that ceramic package and I am sure you could get a bodge wire to bridge it over the crack after repairing the substrate with super glue!
Give it a go!
Yeah... I was thinking about a dremel too, it may work..
I recently aquired an Agilent 54615B 500MHz like this one (only 1GS/s though) and I've got to admit... I love the thing. I use it more than any of the others, lately. It was in much better condition than the one in the video and only needed a little cleaning up. It has the top mounted probe pouch, which still looks brand new, and the scope works like a dream. It doesn't appear to have been used much... none of the usual worn down labels and stuff. I got it so cheap, I'm afraid that if I mentioned the price I'd be arrested for theft. Best price on a new Hantek 50MHz scope, on feeBay, is quite a bit higher.
Great video! I enjoyed watching!
Really enjoyed that Dave. Nothing quite like seeing the process from start to successful finish. Would make a great scope for anyone now- even if its left as single channel. Cheers!
Dave,
You got me super interested with this repair, old school cpu address lines being used to strobe the controls, very similar to the old keyboard reading method in 8 bit computers.
I thought about the 74LS2XX bus transcevers as well, old school :-D
The connections that goes to drilled holes is to keep all the golden pads connected during production - this is used when doing the immersion gold.
zaprodk That makes a good deal of sense since they do require uninterrupted electrical connections during the gold plating operation.
Seeing that purple hybrid gave me cold memories (Those often drift/fail in 3458A DMMs, causing a replacement of ADC board for over a grand USD). No peaking inside cracked hybrid? Could be interesting under Tagano microscope ;)
Excellent example of how troubleshooting can change your symptoms and thoroughly confuse the repairman. As an electronics technician I have seen more than my share.
Fantastic video!
At 32:20 I was wondering about dry or cracked S.M.T. solder joints. I wanted to reach through the screen and push on some chips to find that dry joint. High tin solder is suspect.
Great work Dave , as a rule for repairing I use a scope probe and push PCBs down with light pressure to see if the symptoms show any sign of dependency . I then hook onto a device that is soldered with the hook and pull board upward gently ..looking for the same . I can't tell you how many times I found stressed solder joints or cracks in board cracks normally suggest impact from my experience. It also is apparent that screws , connectors , chips with pin mounts are all mechanical areas of Faure for older boards especially if they have had some impact. Nice 👍 work
I had decided to study semiconductor devices lecture but than I saw this video's notification and then...... a whole hour just passed :D
Thanks Dave, you are such an inspiration for me :D
Exactly the same thing happend to the HP54600B I was transporting in the car. Front panel got a bump in the car and put a hairline fracture in the front panel pcb. A few links later and Bobby Dazzler!
Love these era HP scopes.
Repair/troubleshoot vids are my fave.Thumbs up or sure!
Great job, Dave! That was tough unit, especially given all the DIFFERENT things messed up with it.
Try to find more stuff to fix.
A late feedback - but thank you for this repair - I am sitting with two of these family scopes with button and rotary issues - I got both really cheap from ebay - intending to repair and this video was really intructive, exposing the rabbit holes... :-) thank you Dave!
I noticed that you have your new EEVblog multimeter and looking forward to the review.
amazing how fast it starts up and responds.
Great job. I love watching your testing and teardowns.
Not long time ago I hand-soldered a small batch of 2 layer boards, few of which didn't work during test. After some checking, replacing few ICs I found that some vias were broken straight from manufacturer.
In my experience you can find cracks reasonably easy with one or two layer boards (sometimes up to four layer depending how the middle layers are routed) by holding the board against the sun at an angle. The light traveling through the board will be blocked by the crack, producing a darker line often at an odd angle to the traces.
A lamp that produces reasonably parallel light will work also.
LED light maybe?
"Always look out for any dodgy tantalums." - Recently had one tantalum cap explode on me and found another that had split in half some unknown time ago. Both in Williams pinball machine sound boards. Replaced with MLCC but haven't tried thumping them :-)
Watched the whole session! Great job.
winner the circuit board breakage A big bravo for this troubleshooting
First I see him finally repair something, even just half repair. Great video.
Dave, don't know if it's been mentioned, but to repair the hyprid module - tin the 3 or so broken tracks with silver solder (lead-free) don't use lead based or you'll strip the tracks clean off the ceramic, flux it up good and proper and heat the smaller broken side up with your hot air gun while pushing the two halfs together - you should have rejoined the brroken tracks at this point almost seamless, once your sure - super glue the crack along the top. Should be working after that.
It's cracked *under* or on the edge of the ceramic cover plate.
Ahh didn't spot that. chances are slim then - still might be worth giving the above technique a shot but it'll be trickier. can't break it anymore than it already is i suppose
dom291 Old Tek scopes came with a reel of silver solder inside the case. This was because it used ceramic tag strips that had to be soldered with silver solder.
I've had this "InEr" on my new BM789 after spraying the smallest amount of electronics contact-ol (like deoxyt) into the probe sockets. After opening the unit I cleaned the pcb around the probe sockets and it fixed it. Seems that the probe detection cct is very sensitive.
So, you could try to clean up the pcb of any residue and see how it goes.👍🏻
Woops, I posted in the wrong video.
we have this model in our local maker space have repared two tines with out some dokumention, first time some r27 has getting larger in the power supply, found the tip in some forum
Thanks Dave. I've had my share of cracks n jump wire adventures. Congrats on find! Cheers!!
Classic EEVblog-stuff! Yay! ^^)
That was a fun one to watch, M'Lad!
I love this scope, nice to see you taking it apart so I don't have too. So many bits ;-)
I've been lucky powering it up and if no smoke, running a temperature sensor over the board.. in most cases, it's either cold or too hot. Contact cleaner on the pots really cleans-up the signal, connectors might be next.
I wiggle around all the controls to see if any of the contacts are dirty.
Vacuum it out, pull off the knobs, spray a little bathroom cleaner (foam) on it, wipe it off, and replace the knobs.
This is coming from a technician who has been on the track a long time.
Great video Dave - thanks. However, would like to see the trace repairs and work on that.
I use to work in the lab at LM ericsson, making phone systems a few years back.
When I start working there the lab looks like a cartoon lab with stuff just everywhere...
So I started making identical work stations so everyone could work at the same time.
So I go down in the cellar and looked and there was those HP around everywhere. Was like 20 of them around. I just needed like 6 or 7 of them. Pretty much every single one of them was different. They all looked identical. But was different specs and functionality.
Really enjoyable repair that Dave! :)
I worked with lots of large hybrids, but I never saw a pogo socket like that: Ours were always PGAs into ZIF sockets. But we weren't pushing GHz signals around.
really enjoyed that repairathon Dave. :)
My new favorite Dave quote: "We're just viewin' the signals for kicks"
repair videos are my definite favorite. keep it up Dave
I have the HP 54602B (150Mhz) which is pretty similar to this one. *great* scope. The pass/fail mask feature is pretty neat. Purchased a new battery backed ram module a year or so ago, i'm sure the original one will die one of these days.
Recently had a 16534a with the same hybrids and reseating them did the trick!
Actually the erratic rotary encoders are easier to fix than you think. It happens because they have been sitting for too long unused. Just dial them in each direction 100+ times and you'll see it improve gradually. I got lazy and grabbed the encoder shaft with power tool chuck and it works brilliantly.
I repaired two units in the same 54600 series with broken keypad PCB like a decade before. It happens not because of the manufacturing quality, but somebody who opened up the keypad later (attempting a repair) forgot to slide the PCB under the hooks first before putting the screws on, inevitably bending the PCB until it cracks.
Now I have so many of these units that I just wouldn't bother saving one of those cracked front panel keypads.
*Vielen Dank* für dieses Video!
Bei Deinen Rep. lerne ich immer wieder neues!!
Would have loved to see how you "fixed" the broken lines and strengthen the board. Had similar issue with mine, removed green coating and joined the line with a thin wire but always feel it would break again overtime without putting a real reinforcement on the board... Anyways, awesome content as usual, keep it coming!
Old HP54600 series' front keyboard usually crack not from users being rough, but somebody was in the front panel keypad before but didn't know better to slide the board under the retainer but instead they just forced the board above the retainer clips with screws. The repair guy thought they got away with not RTFM and over time the board fractured from the unnecessary stress from the retainer
Wish I had a scope that nice. Brilliant video!
I have a 54601A, 100MHz, 4 channels that I was lucky to get on a local junkyard for $70. It was being sold as non functional, but I found before buying that it was just the bright control that was at the minimum... It doesn't have all good stuff of modern osciloscopes but is good enough for my hobby activities.
Fantastic vid! :D Maybe try de-capping the cracked hybrid if it's all the same at this point? Might be interesting. Thanks!
Spent many an hour pressing those scope buttons debugging high speed radio modems.. good memories
That was *_GREAT_* Dave!!! Thank you!!
that was awesome. I have an HP 54201D that has a faulty input and now I want to take it apart. I didn't know they had 68000 chips in them!
Good one Dave. The repair videos are the best.
20:18 Stop showing off your scopes to the poor graduate students
around the globe!
Repair videos are the best! Loved it!
I expect the high speed buffers are to ensure fast release time on a shared external bus on 68000 also running code to memory to meet bus timing.
Nice to see you killed the EEVBlog curse Dave... nice find and nice result, loved the video thanks
Excellent information in this video. Thanks for sharing
When it's obviously taken a good bounce off the floor, first thing to assume is a cracked PCB somewhere. If it landed on the front panel, you'd have stress points where the pots took the force of the impact.
At 52:30, to the right of the large crack, near the diode, is that another small crack, across a Y/T track intersection?
Bloody relieved that you fixed it, always disappointing when you try everything and you can't get it working, or you Get it partly working. That's not a criticism of yourself, but there's a tension as to if you can fix it or not :)
32:14 Well, I see a 68000... It's surprising how many products that thing found its way into from the Mac to the Saturn to this random oscilloscope
8 Bits you are only 8 bit you have no bussiness around a 68k... go play with a z80 😂
Thanks, Dave - well, I was wrong, but lesson learned: A methodical approach is best.
Good video, Dave - Better than the disaster of the Dumpster-Dive TV repair..... lol! Thank you :-)
Brillant, I want to be able to do this someday, how satisfying to watch
Great video. Great to see all the effort you went to.
How about testing a few of these DIY oscilloscope kits you can buy on ebay and build yourself, and see if those are good enough for your beginner DIY hobbyist? They're very cheap, 30-40 bucks so well within the range for early beginners. Search for DSO138 or DSO150 or similar, made by JY Tech. Could be a great start for beginners who are on a budget and can't afford a proper oscilloscope if they're useable for basic situations. :)
My 100MHz Tektronix 465M cost $30AU ;D
Yeah my Tek 465B was $100 but I got a little heathkit signal generator and a logic analyzer with it as a package for that price in the classifieds.
I've just finished debugging one of those that my brother built for fun. it was his first solder project and he was tearing his hair out as to why it did not work. long story short: the microcontroller is soldered on by JY Tech and 5 of the pins were loose or intermittent...
the poor guy almost gave up and brought it over as last resort. working now and zero percent his fault..
Well, it is chinese so bad soldering does happen I suppose... :) Might not be the best kit for a first kit building project, but it's a great and cheap way to add an oscilloscope to the toolbox, and a very portable one at that. :)
Saving money and getting a cheap oscilloscope kit like the DSO138 or 150 may be very valid in some countries as well. As an example, in my country, Norway, you have to pay 8-900 US dollars for an HP 54603B used... Insane price, and nobody in their right mind would pay that, but that's the price in Norway.. Ordering internationally is expensive as these big classic CRT oscilloscopes are heavy and expensive to ship... Where I live now, the Philippines, I can't even find a decent used oscilloscope. So one of these kits would be a great way to get started in a situation like that... :)
??? How did you replace the traces? Mod wire to good traces?? Foil copper over broken traces soldered into place and solder masked?? Epoxy resin or super glue on the crack? How did you decide which methods to use???
ALSO ASKING ANYONE WHO IS EXPERIENCED IN ELECTRONIC REPAIR TOO!!
Usually when it's a section of buttons/dials not working in a keyboard in general (even a good old computer keyboard that I'm typing this comment on), it's almost always a physical crack/disconnect in the lines. I'm surprised Dave chased it down to the active components before taking the front panel keyboard out for an inspection.
Some of the Infiiinium scopes used those hybrid A/D converters as well.
Did you do anything to stop the PCB crack from propagating further? I would consider drilling relief holes at the ends and/or reinforcing with epoxy and fiberglass fabric. I also would probably epoxy that hybrid end back on and splice the traces until the replacement arrived.
I have always cleaned rubber membrane switches in the sink with mild dishwashing soap.
Funny you make this video now... just yesterday I pulled a perfectly functioning HP54601A from the scrapyard.
Ah.. this scope brings back memories. You can actually activate an easter egg and play tetris on it
Sorry for very late replay, but how u can do it?
Thanks for the video. Just one thing missing, would have loved to see the repair and how your repaired the board.
Have a day
That was a fun show... Nice work..
This was AWESOME, thanks Dave!
What a long debug. Glad you finally figured it out.