3:48 «and the fuses don't blow on their own!» I learned this the hard way. Working on trying to salvage a rather beefy PSU for a light, i saw it had some burn marks around a mosfet and a blown 10A fuse. I decided to swap the fuse, clean up the board with some alcohol and powered it on… BOOM. Thre was a loud explosion and the room went dark. Well, apart from the board which burned like a bonfire. Turns out something had gone terribly wrong to the previously burnt mosfet which caused it to blow up into pieces. This incident swiftly sparked a fire in the not-quite-dried-up-yet alcohol. The entire board was burning, from edge to edge. It was actually a spectacular sight. Decided to toss that one in the bin. I did a pretty darn good job as a rookie pyrotechnic that day though lol
I recently restored a Dynacord GIGANT amplifier from 1969. It was a total nightmare. 79 capacitors, several resistors and transistors, new tubes, some bad pots, and so much more. After three months it's finally restored to all it's glory.
I found Mark whilst searching for some info of how to repair my Sony RCD-W100 CD player. His exploits in the world of repairing all sorts of audio equipment really is quite captivating. Never have I seen such electronic expertise demonstrated in such a charismatic way. Just amazing!! Thank you Mark.
It's videos like these that further fuels my desire to continue to learn how things work as well as my beliefs of "why buy it when you can build it" and "why replace it when you can fix it". Great videos, please keep them coming!
Well done Sir. I would definitely have changed out those regulators and smoother caps because they've clearly been under extreme load due to the tantalums. The fuses did flash perhaps they need to be a surge tolerant type. I love this older gear its what I was raised on and so nicely built. I design a lot of my own stuff and I still build it through-hole in the same way and avoid SMD.... It's proven to be such reliable technology
Great video. I really enjoy your jolly, good nature, chuckling at every challenge. You set a fine example for me. I tend to get a bit grumpy when encountering setbacks. You've given me renewed vigor to tackle a troublesome effects unit I've left lie for a bit. Subscribed!
I had the crappiest day I've had in a long time at work today. Just binged about 4 episodes and laughed my butt off while putting the finishing touches on my Trio TW-61. Thankyou sir!
Mark, I've been in the same field as you for over 40 years. I considered myself a bit of a fancy pants... And indeed I would have repaired the majority of the items I've seen on your channel.. But, I have to say the more I've watched, the more I concede you are an absolute master. Certain things take you way beyond the ordinary. Making knobs or whatever.. There is always something you do that nobody else would, except maybe on occasion... You treat every repair the same, and every repair gets the full treatment. Sort of amazing. My only gripe is with the opening sequence. I don't like the music. That is it. Love the channel.
I'm sorry I have to disagree with you on the choice of music, as he fixes vintage equipment. It's so him, and it's a nicely edited sequence which I think compliments the track. (I especially enjoy the human capacity discharge shot.) ⚡ Looking forward to the next episode...
After you replaced 2 of the gold filter caps, I was yelling at ya through my screen to change all of them 😂. I'm glad you eventually did. Ya know... only a matter of time with those oldies. Great work as always! Cheers!
Another great video, Mark. I have a lot of respect for Dynacord equipment. About twenty years ago I used to play regular concerts in a bar that had a Dynacord Powermate 600 powered mixer. It looked like it had been soaked in beer, dipped in cigarette ash and then hit by a freight train, bt it still worked perfectly and sounded great. I was so impressed that I bought my own Dynacord Powermate 600 and it hasn't missed a beat. I guess that Dynacord have moved manufacturing from Germany to China these days but they still have an excellent reputation.
7:42 "Black screws on a black surface" That is what Zaphod Beeblebrox said when he was in Hot Black Desiato's stuntship. "You press a black button and a black light turns on ...." Hitchhikers Guide to the Galaxy 😊
I have a few of the old Dynacord delay units for speaker delay. The battery dies and can leak. Think i replaced a few other things, a cap blew too i think, after years of no use. I didn't have the correct battery and needed it the next day. I had old lithium batteries that look like AA much bigger backup batteries. I couldn't solder to them so had to modify a battery cage and fit the larger battery that way. Pulled off a mini festival in a circus tent. very cool.
I love the videos Mark, I look forward to new ones being made. Really enjoyed this one in particular, it's a really nice old delay, I'm so happy you got it fixed. It's pretty rare here in the US and quite pricey! Keep up the good work! Thank you Rb
I tryed soldering last night. It`s hard with cataracks lol. Looked a mess this morning in the light. I fix al sorts of things. love this channel. Wish I was so clever.
I don't know how often you get a synthesizer over to repair, but I'd love to see a video of that, this comes somewhat close at least as an FX processor. Something like, a 1970s Moog, a 1990s Access Virus, a Roland Jupiter or even anything modern like a Novation Summit would be amazing to watch for me and many other synth enthousiasts i'm sure. Digital or analog doesn't matter. Love your channel! As an electronics hobbyist I hope I can one day repair like you!
When I was still training, like in 1977, I used to maintain stuff on Ferries, fromrRadar, radios and to teletennis machines. I remember the size of the boards in them, about 2 feet by 18 inches, SRBP boards, which used to warp because they were crap, absolutely packed with 74xx chips, literally hundreds of them.
sounds like a bbc sounds affect tape/record i was waiting for the doctor to appear or a darek to bust through the door screaming exterminate😆. it amazes me how a spent cap can cause them kind of problems another excellent video mark
A renaissance man of electronic repairs indeed! Excellent troubleshooting skills Mark!! I'm looking forward for your next episode! - I reciently came across your channel - I've been binge watching it ever since! Thank You!
Fantastic channel. Really fun seeing how you repair stuff. Love how informative it is. Getting this wholesome feeling as well. How you don't have 50 X more subs is beyond me. Keep up the amazing work! :)
Those Roederstein caps always seemed to failed short! And the brown plastic ones don't usually fair much better, as anyone who's worked on vintage B&O equipment will know. Glad you blanket replaced the crucial ones!
Old school for me I had change 15 leaky electrolytic capacitors for my 90s 1 pre-amp tube compressor/limiter and luckily I cleaned the board and it's fixed and it's about the 6th time I've turned it on since I've never used it. I like it more that I fixed it!
18:04 Mark, I think you just composed the next science-fiction movie theme! I think this unit has had a rough life in some studio somewhere. Great video as usual mate, thank you!
You know I love how you fix it and then you notice some other problems with the potentiometers and capacitors and you decide to fix them too. Some repair text might say, oh I got it working and fixed its main problem and that's good enough, not you you make sure it works how it's supposed to work.
Brilliant repair! I did wonder about the 'hot' tants near the start, they were showing as 34 and 28C on the Flir, not a huge temperature I would have thought? It's one problem with the auto-ranging on these meters that things appear 'white hot' when they're just the warmest thing in shot.
I discovered you channel a few days ago... Nice video's, verry interesting to see a colleague repair man puts a lot effort on this equipment! Looking forward to seeing the other video's! Thanks! Greetings from the Netherlands. 🤗🤗🤗
Hi Mark… I am a follower of your videos from Canada. Excellent work! … just occurred to me that I have an “vintage” Sony cassete deck TC 165 that needs attention… I know it’s not worth much, but sentimental value has no price…. Could be a nice piece for one of your videos, no? 😃 … anyway, congratulations and hoping for the next one!
😆 2:21 STILL have mine Sinclair Spectrum! 😂 I have it in 1985! ans still the software on cassette tapes and some books and wrote the software lines, and one dot missing and its not working ore stops at that moment. also have then original tapedeck for that. pfffff..... 38 years ago, where is my time goes? 😊
Hey Mark, thanks for your channel. The most thing I like you is your smiling, happy face. Most of the electric and electronics professionals will have wrinkled forehead and tension (more over filled with ego). I really feel so happy till the end of your videos. Ohh BTW what is that foam spray that you used to clean the exteriors?
Great video and awesome repair! Quick tip: the tang on those pots can be easily removed with side cutters, they are quite brittle and come off pretty clean
Just found your channel, I loved the vid - but.... I've worked with MEK in the past, you really want to respect that shit. At the very least use gloves. A respirator or fume hood would also be wise. The vapor is very flammable.
Hello friend, I send you greetings from Spain. I appreciate the time you spend showing us your work, it is very valuable information. I like the audio of your videos, the sound of the tools and equipment manipulation is relaxing. I would like to ask you for a repair video with only audio of the ASMR type. All the best.
Now that's in interesting request! I do deliberatly run some gear for the background fan noise (best sound is the 60 year old Tektronix 453 Oscilloscope), as I find it is more forgiving in the edit. My daughter also tells me that her friends watch me at night, as they fall asleep! Unfortunatly, I don't have the ASMR reaction, despite watching @WhispersRed ASMR channel. Perhaps I need more practice.
I must admit to a grudging admiration for your "let's push some joules into this & see what glows" approach when faced with a short. I work a lot on revox gear, & this wouldn't work- before you found the duff cap buried in the middle of an audio card, you'd fry off the delicate tracks on the PCBs. I always think revox boards look like they were made by a talented but highly strung silkworm.
ROE caps are praised by audiophiles, but when i open any device this old, and it is valuable device worth saving i replace all ROE caps with higher grade Japanese ones.
always impressed with your knowledge of what to do - how did you acquire such learning Mark - if I may ask. It's a pleasure watching how you diagnose and repair these pieces of equipment. Loved it when you connected the speaker - it sounded like the beginning of a Hawkwind album - awesome!
The inrush current looks quite close to breaking those fuses looking at the glow - even after replacing some old components. I guess its common for old components to draw more current than when they were new. I wouldn't be surprised if those fuses blow again after a few power cycles, especially is the unit is used in a warm rack.
I have repaired quite a few devices, and often, you can see the wires in the fuses move when turning on the power. But if they light up, I would replace them with slightly higher rated ones, even if they are slow-blow fuses.
The troubleshooting, and cap replacements you found, will fix a huge amount of old gear which has failed. My test gear is very similar to yours and I picked up most of it very cheaply due to it not working. Dozens of tantalum caps later and I have all working gear. Let me know if you are ever in the Boston area or if you are going to the Dayton flea market, it would be fun to get together.
Seems to be the case! But do you replace w new tants or something else? I’m thinking they’ll last long enough… are they made the same as before or better?
@@2tallB I'll give a big "it depends." In some applications (Watkins Johnson receivers come to mind) they used wet slug tantalums and there is no way an electrolytic will fit in the space. So the replacement must be the very pricey duplicates. In most other cases a 105C electrolytic is more than sufficient. But beware, if you are working on specialized equipment which is designed for extreme temperatures you must replace with compatible parts which frequently means mil-spec hermetic electrolytics or tantalums. Another note with tantalums is that when they originally came out their manufacturers recommended ones rated just over operating voltage. So for example 15 volt parts used on 12 volt supply rails. This proved to be bad advice once there was enough field experience. So use higher voltage rated parts, for example 25 volt parts to replace the 15 volt ones. This will greatly extend life.
@@flyer617 thanks for your reply. I would just put another tant in, but I’ve seen it’s a pretty hot topic. (No pun intended!) I notice that they are utilized for speed as well so, like you said, it would depend on the circuit. I’m gradually learning, your comments help.
Fuses glow because you used standard not time delay, ,ou can Just See the T suffix ont the mask. Nice save, good work with the Pots when I saw the one in bits I thought you would try to reassembe it.
Great work, I love to see older audio gear being salvaged. However, butanone is a known skin irritant, as well as being flammable, and shouldn't be handled with bare hands.
3:48 «and the fuses don't blow on their own!»
I learned this the hard way. Working on trying to salvage a rather beefy PSU for a light, i saw it had some burn marks around a mosfet and a blown 10A fuse.
I decided to swap the fuse, clean up the board with some alcohol and powered it on… BOOM. Thre was a loud explosion and the room went dark. Well, apart from the board which burned like a bonfire.
Turns out something had gone terribly wrong to the previously burnt mosfet which caused it to blow up into pieces. This incident swiftly sparked a fire in the not-quite-dried-up-yet alcohol. The entire board was burning, from edge to edge. It was actually a spectacular sight.
Decided to toss that one in the bin. I did a pretty darn good job as a rookie pyrotechnic that day though lol
I recently restored a Dynacord GIGANT amplifier from 1969. It was a total nightmare. 79 capacitors, several resistors and transistors, new tubes, some bad pots, and so much more. After three months it's finally restored to all it's glory.
I found Mark whilst searching for some info of how to repair my Sony RCD-W100 CD player. His exploits in the world of repairing all sorts of audio equipment really is quite captivating. Never have I seen such electronic expertise demonstrated in such a charismatic way. Just amazing!! Thank you Mark.
It's videos like these that further fuels my desire to continue to learn how things work as well as my beliefs of "why buy it when you can build it" and "why replace it when you can fix it". Great videos, please keep them coming!
Mark is a Renaissance man of repair! Amazing work.
Japp 👍🙂
Well done Sir. I would definitely have changed out those regulators and smoother caps because they've clearly been under extreme load due to the tantalums. The fuses did flash perhaps they need to be a surge tolerant type. I love this older gear its what I was raised on and so nicely built. I design a lot of my own stuff and I still build it through-hole in the same way and avoid SMD.... It's proven to be such reliable technology
Agree about the regs and certainly those fuses.
Great video. I really enjoy your jolly, good nature, chuckling at every challenge. You set a fine example for me. I tend to get a bit grumpy when encountering setbacks. You've given me renewed vigor to tackle a troublesome effects unit I've left lie for a bit. Subscribed!
The sound from the speakers reminds me of the classic sci fi movie Forbidden Planet. Good job as always Mark.
I had the crappiest day I've had in a long time at work today. Just binged about 4 episodes and laughed my butt off while putting the finishing touches on my Trio TW-61. Thankyou sir!
It's a pleasure to watch someone who knows what they are doing
Mark, I've been in the same field as you for over 40 years. I considered myself a bit of a fancy pants... And indeed I would have repaired the majority of the items I've seen on your channel.. But, I have to say the more I've watched, the more I concede you are an absolute master. Certain things take you way beyond the ordinary. Making knobs or whatever.. There is always something you do that nobody else would, except maybe on occasion... You treat every repair the same, and every repair gets the full treatment. Sort of amazing.
My only gripe is with the opening sequence. I don't like the music. That is it. Love the channel.
I'm sorry I have to disagree with you on the choice of music, as he fixes vintage equipment. It's so him, and it's a nicely edited sequence which I think compliments the track. (I especially enjoy the human capacity discharge shot.) ⚡ Looking forward to the next episode...
After you replaced 2 of the gold filter caps, I was yelling at ya through my screen to change all of them 😂. I'm glad you eventually did. Ya know... only a matter of time with those oldies. Great work as always! Cheers!
Another great video, Mark. I have a lot of respect for Dynacord equipment. About twenty years ago I used to play regular concerts in a bar that had a Dynacord Powermate 600 powered mixer. It looked like it had been soaked in beer, dipped in cigarette ash and then hit by a freight train, bt it still worked perfectly and sounded great. I was so impressed that I bought my own Dynacord Powermate 600 and it hasn't missed a beat. I guess that Dynacord have moved manufacturing from Germany to China these days but they still have an excellent reputation.
Beer, cigarette ash and freight trains... Just like any other day at the pub!
Хоть я и мало,что понимаю в английском, но вы большой молодец.
Привет от радиолюбителя из России, конкретно город Омск.
Where ever you are fixing this stuff, I hope the people appreciate the great work you do
Mark you never disappoint, excellent work mate, and a joy to watch.
Your skill and patience is amazing 😊
been doing this for 58 years and you are a good tech.
7:42 "Black screws on a black surface"
That is what Zaphod Beeblebrox said when he was in Hot Black Desiato's stuntship.
"You press a black button and a black light turns on ...."
Hitchhikers Guide to the Galaxy 😊
Love your work, excellent presentation...1st class Mark !!!
Hi Again Mark, Another brilliant repair presented in a manner that makes electronics interesting with the right presenter. Keep up the good work
I have a few of the old Dynacord delay units for speaker delay. The battery dies and can leak. Think i replaced a few other things, a cap blew too i think, after years of no use. I didn't have the correct battery and needed it the next day. I had old lithium batteries that look like AA much bigger backup batteries. I couldn't solder to them so had to modify a battery cage and fit the larger battery that way. Pulled off a mini festival in a circus tent. very cool.
Mate, The Clangers have arrived in your workshop!😄
Thanks
I just came across to your channel. I find it very interesting and liked it. You are joyful, confident, know what to do and how to do. Keep it up Mark
I love the videos Mark, I look forward to new ones being made. Really enjoyed this one in particular, it's a really nice old delay, I'm so happy you got it fixed. It's pretty rare here in the US and quite pricey! Keep up the good work!
Thank you
Rb
I tryed soldering last night. It`s hard with cataracks lol. Looked a mess this morning in the light. I fix al sorts of things. love this channel. Wish I was so clever.
Mark, we love you. Thank you making these videos. Amazing work!
I don't know how often you get a synthesizer over to repair, but I'd love to see a video of that, this comes somewhat close at least as an FX processor. Something like, a 1970s Moog, a 1990s Access Virus, a Roland Jupiter or even anything modern like a Novation Summit would be amazing to watch for me and many other synth enthousiasts i'm sure. Digital or analog doesn't matter. Love your channel! As an electronics hobbyist I hope I can one day repair like you!
When I was still training, like in 1977, I used to maintain stuff on Ferries, fromrRadar, radios and to teletennis machines. I remember the size of the boards in them, about 2 feet by 18 inches, SRBP boards, which used to warp because they were crap, absolutely packed with 74xx chips, literally hundreds of them.
18:05 - sounds like the soundtrack to a Pat Troughton era episode of Doctor Who!
Loved the soldering-iron-on-the-screw trick. Need to remember that.
sounds like a bbc sounds affect tape/record i was waiting for the doctor to appear or a darek to bust through the door screaming exterminate😆. it amazes me how a spent cap can cause them kind of problems another excellent video mark
Excellent work, as usual. You make it look so easy.
That was an involved job. But such a beautiful vintage device. I still have all my old 80s gear
A renaissance man of electronic repairs indeed! Excellent troubleshooting skills Mark!! I'm looking forward for your next episode! - I reciently came across your channel - I've been binge watching it ever since! Thank You!
had a similar one a long time ago - was quite a pleasure - good memories !
Thanks for another great video Mark. I'm pleased that I found your channel.
Fantastic channel. Really fun seeing how you repair stuff. Love how informative it is. Getting this wholesome feeling as well. How you don't have 50 X more subs is beyond me. Keep up the amazing work! :)
That was really interesting when those two fuses lit up!
I wonder if the fuse wire has a coating on it? Maybe it just burns off on 1st use?
Hi Mark . The ROE Capacitors are very bad Capacitors.
Great Video . Thanx from Germany
Great video on a professional unit. All tantalum caps are time bombs. I've seen them blow their tops off!
You are really good at explaining what's going on as I actually felt like I understood what you were doing, great job :)
Yay, 2K subscribers! Congrats. Rising rapidly and deservedly so.
Those Roederstein caps always seemed to failed short! And the brown plastic ones don't usually fair much better, as anyone who's worked on vintage B&O equipment will know. Glad you blanket replaced the crucial ones!
Ll
Can confirm! I had a Systron-Donner PSU at work with a dead channel. Turned out it was a shorted golden ROE. Dead short!
@@brainbuginfestation8548 They've definitely become a 'replace-on-sight' item, much like the dreaded RIFA X2 bomb!
Those Brown caps used in Quad hifi gear in the 1980's
i have always considered B&O to stand for Body & Odor of audiophile.
Old school for me I had change 15 leaky electrolytic capacitors for my 90s 1 pre-amp tube compressor/limiter and luckily I cleaned the board and it's fixed and it's about the 6th time I've turned it on since I've never used it. I like it more that I fixed it!
Another great one. Your methods are sound and you are very thorough. Really great work.
18:04 Mark, I think you just composed the next science-fiction movie theme! I think this unit has had a rough life in some studio somewhere. Great video as usual mate, thank you!
Enjoyed seeing this DDL relic bought to life!
Most people I don’t think appreciate you very positive attitude whiz is hard to come by in life these days.
You know I love how you fix it and then you notice some other problems with the potentiometers and capacitors and you decide to fix them too. Some repair text might say, oh I got it working and fixed its main problem and that's good enough, not you you make sure it works how it's supposed to work.
Another great video Mark. Very interesting as usual. Thank you
Dynacord, really the top of the crop i think,. lovely repair thanks for the video
Brilliant repair! I did wonder about the 'hot' tants near the start, they were showing as 34 and 28C on the Flir, not a huge temperature I would have thought? It's one problem with the auto-ranging on these meters that things appear 'white hot' when they're just the warmest thing in shot.
Excellent Mark. Love the Channel and your expertise. Brilliant.
I watch your channel for hours!
I discovered you channel a few days ago... Nice video's, verry interesting to see a colleague repair man
puts a lot effort on this equipment! Looking forward to seeing the other video's!
Thanks! Greetings from the Netherlands. 🤗🤗🤗
Hi Mark… I am a follower of your videos from Canada. Excellent work! … just occurred to me that I have an “vintage” Sony cassete deck TC 165 that needs attention… I know it’s not worth much, but sentimental value has no price…. Could be a nice piece for one of your videos, no? 😃 … anyway, congratulations and hoping for the next one!
😆 2:21 STILL have mine Sinclair Spectrum! 😂 I have it in 1985! ans still the software on cassette tapes and some books and wrote the software lines, and one dot missing and its not working ore stops at that moment. also have then original tapedeck for that. pfffff..... 38 years ago, where is my time goes? 😊
Hey Mark, thanks for your channel. The most thing I like you is your smiling, happy face. Most of the electric and electronics professionals will have wrinkled forehead and tension (more over filled with ego). I really feel so happy till the end of your videos. Ohh BTW what is that foam spray that you used to clean the exteriors?
You always pull through on repairs good work
those flat toggles remind me of my early days as a musician in in the late 80s early 90s!
Great video and awesome repair! Quick tip: the tang on those pots can be easily removed with side cutters, they are quite brittle and come off pretty clean
That is the thing with Dynacords. Wonderful engineering, caps and pots always fail, often switches too.
Just found your channel, I loved the vid - but.... I've worked with MEK in the past, you really want to respect that shit. At the very least use gloves. A respirator or fume hood would also be wise. The vapor is very flammable.
Hi sir really your are genies, your are grant service Engineer i like you servicing method thank you once again.
Interesting about the Tanalum caps... we always suspected them shorting even back in the 80's.
This was highly entertaining. Thank you!
great stuff, watching all your videos, Mark you should be on TV. entertaining, educational and very interesting, thankyou for your hard work. ay it
Really i like that smile 😁 for us ❤
Always a joy to watch your videos. One question, when you find a leaking or shorting capacitor why wouldn't you replace all of the similar capacitors?
Dynacord DDL 12 - Studio/Rack FX, product released Aug 1983 which is very early for digital effects.
Hello friend, I send you greetings from Spain. I appreciate the time you spend showing us your work, it is very valuable information. I like the audio of your videos, the sound of the tools and equipment manipulation is relaxing. I would like to ask you for a repair video with only audio of the ASMR type. All the best.
Now that's in interesting request! I do deliberatly run some gear for the background fan noise (best sound is the 60 year old Tektronix 453 Oscilloscope), as I find it is more forgiving in the edit. My daughter also tells me that her friends watch me at night, as they fall asleep! Unfortunatly, I don't have the ASMR reaction, despite watching @WhispersRed ASMR channel. Perhaps I need more practice.
@@MendItMark Please don't do ASMR, your commentary and the workshop sounds are appreciated.
ASMR is creepy.
This is such an excellent channel. Very enjoyable to watch.
wow! out of all devices in the world you got this one! :D I have one broken DDL 12 too! I'd really like to fix it / have it fixed.
I must admit to a grudging admiration for your "let's push some joules into this & see what glows" approach when faced with a short. I work a lot on revox gear, & this wouldn't work- before you found the duff cap buried in the middle of an audio card, you'd fry off the delicate tracks on the PCBs. I always think revox boards look like they were made by a talented but highly strung silkworm.
Good morning we love electronics and repairs and restoration of appliances we are together..one more writing...go my like always
ROE caps are praised by audiophiles, but when i open any device this old, and it is valuable device worth saving i replace all ROE caps with higher grade Japanese ones.
The most failures are related by dry capacitors. 1983 is a long time ago and the ELO Caps are well known, getting dry. Nice work...
always impressed with your knowledge of what to do - how did you acquire such learning Mark - if I may ask. It's a pleasure watching how you diagnose and repair these pieces of equipment. Loved it when you connected the speaker - it sounded like the beginning of a Hawkwind album - awesome!
The inrush current looks quite close to breaking those fuses looking at the glow - even after replacing some old components.
I guess its common for old components to draw more current than when they were new. I wouldn't be surprised if those fuses blow again after a few power cycles, especially is the unit is used in a warm rack.
They were supposed to be time delay fuses.
Thanks for the video Mark, very interesting repair
I've had many issues with old ROE capacitors and that unit is full of them!
You have massive equipments library
Mark you are super cool to watch
I have repaired quite a few devices, and often, you can see the wires in the fuses move when turning on the power. But if they light up, I would replace them with slightly higher rated ones, even if they are slow-blow fuses.
The troubleshooting, and cap replacements you found, will fix a huge amount of old gear which has failed. My test gear is very similar to yours and I picked up most of it very cheaply due to it not working. Dozens of tantalum caps later and I have all working gear. Let me know if you are ever in the Boston area or if you are going to the Dayton flea market, it would be fun to get together.
Seems to be the case! But do you replace w new tants or something else? I’m thinking they’ll last long enough… are they made the same as before or better?
@@2tallB I'll give a big "it depends." In some applications (Watkins Johnson receivers come to mind) they used wet slug tantalums and there is no way an electrolytic will fit in the space. So the replacement must be the very pricey duplicates. In most other cases a 105C electrolytic is more than sufficient. But beware, if you are working on specialized equipment which is designed for extreme temperatures you must replace with compatible parts which frequently means mil-spec hermetic electrolytics or tantalums. Another note with tantalums is that when they originally came out their manufacturers recommended ones rated just over operating voltage. So for example 15 volt parts used on 12 volt supply rails. This proved to be bad advice once there was enough field experience. So use higher voltage rated parts, for example 25 volt parts to replace the 15 volt ones. This will greatly extend life.
@@flyer617 thanks for your reply. I would just put another tant in, but I’ve seen it’s a pretty hot topic. (No pun intended!) I notice that they are utilized for speed as well so, like you said, it would depend on the circuit. I’m gradually learning, your comments help.
Very nice Guy and interesting video,! Regards from Germany
I'm from India and Mark is good 👍
Good job. Happy Christmas!
and have you never heard the expression 'beware the blue tants'. They were absolutely notorious in TVs.
16:52 those top two 200mA fuses definitely got hot there
Beautiful video, thank you 👍😊
Sir goodevening. I am philipino good work sir.
I don't recall ever reading about a failure mode of a capacitor as being "knackered".
Add a little mini moog to your bench, fx processors love a good wave.
thanks for sharing. saludos desde Mexico
i see the smoke tends to always blow directly toward your face too! lol.
Fuses glow because you used standard not time delay, ,ou can Just See the T suffix ont the mask.
Nice save, good work with the Pots when I saw the one in bits I thought you would try to reassembe it.
Great work, I love to see older audio gear being salvaged. However, butanone is a known skin irritant, as well as being flammable, and shouldn't be handled with bare hands.