The tortuous Pioneer CT-50T tape deck Repair
A few weeks ago I made the video about the Pioneer flip-clock cassette deck. My original plan for that was to show a quick repair at the beginning before moving on to do a demonstration.
The repair turned out to be anything but quick, so by the time I’d got the deck working, I’d recorded enough repair footage for a really dull Blu-ray box set.
Here’s my attempt to condense that repair footage into something watchable.
It’s quite a long video, so is in danger of overstaying its welcome by the end, but that mirrors my experience with the deck itself. If nothing else, at least I can finally reclaim the space on my SSD.
Hope you’re all still holding up well. Apologies if anyone is awaiting a response to an email or message. After I’d turned off the computer to take a couple of days break from the internet I returned to a full inbox. I’ll work on trying to catch up, although I’ve noticed my oldest messages I’d previously flagged to reply to date from Jan 2018, so it may be a while before I’m up to date.
Comments (60)
Matt, you're way too hard on yourself - you really have a mental block over the electronics side of things.. Many of us who ever fixed hifi equipment for a living started out just where you are, fixing by trial & error, learning as we went and getting better the more we did. The electronics side of it is not so difficult, especially with through-hole discrete component stuff. A lot of components can be tested in-circuit with a decent meter and there are plenty of stock faults like resistor values drifting (esp. in valve/crt circuits), dried-out capacitors, dead transistors etc. You clearly have a 'feel' for how mechanical systems work and electronics is the same ; the players are different, the rules are different but you'll see the same patterns appearing time after time. Learn some basic electronic circuit theory, watch some YT videos on ohms law, passive components & theor role in circuits, zener diodes, transistor biasing, power supplies etc. - you'll be surprised how quickly the fog will clear. May I recommend Big Clive's channel - he disassembles a lot of things, electronic & mechanical and explains how everything works in a clear, concise & entertaining way..
I have to agree with some of the other posters above that this was really a fantastic video and along with your prior repair videos but especially this one altogether they have given me a ton more confidence in my ability to attempt to repair similar type components! Items that I would never have thought to open up a myself previously I now can look at and reference your videos and at least get some ideas as to what could be causing the problem and more importantly how to fix it. So I very much appreciate you sharing this video with us it really was fantastic in I'm sure I'll be coming back to it along with your other repair videos in the future. Many thanks!
Well if it helps anyone feel more confident in taking a lid off something and having a look around inside rather than just binning it, then that’s a really good outcome.
Another great video! Out of spec capacitors will easily throw off those wave forms needed for the autostop. I see it quite a lot in the electronics that I've restored that are about the same age as that deck. You can also use a capacitors ESR meter. It let's you measure with the capacitors in the circuit.
I realize this is a bit out there, but if you want I could help you diagnose the auto-stop circuit via video call, and try to explain what's going on at the same time. I have experience fixing lots of audio/video equipment, from my 1960 RCA color TV to CED players and more modern things. Love your videos!
It’s very kind, but due to space restrictons in the house - I’ve had to move the deck to my locker for the moment.
Thanks for the video Mat and well done for getting it to work. If you want remote help with the auto stop do feel free to get in touch. I live with an electronics engineer. Best wishes.
I need to go back and look at the belts I used on my Lucas LS230 car cassette player, it has quite a lot of wow and flutter and I just thought that was just because it was cheap. Probably not. Very nice to see the troubleshooting process anyway.
2121 - A Cassette Deck Odyssey. Fantastic video of your CT-50T and efforts to repair. It struck me just how beautiful that machine is inside apart from anything else. Thank you for doing these things so that we don't have to - or if we do, providing some ideas/guidance. One I'll be watching again with a stack of cheese sandwiches that's for sure.
Very enjoyable video. Thank you!
What's your opinion on replacing original incandescent bulbs/lighting in older devices with an LED equivalent? I know some people are all for it due to better reliability whilst others aren't keen as it affects the 'purity'. Stellar work as always, TM.
I‘ve seen a few pictures of components with bright white VUs and new blue LEDs which don’t look too hot. However I’d happily replace a bulb with a suitable LED - if only I knew what I was doing. I’d have to start messing around with resistors, and that’s not really in my wheelhouse.
Zen and the art of stereo repair.
And people wonder why people like us can't upload a new video every day.... I still have numerous half-repaired items that I have given up on.
If you’ve given up on them I’m pretty sure they’re well and truly knackered.
Thanks for another fun weekend video, Mat! The wirewrapped connections took me back to my early days in computers; we had wire-wrapped mainboards in our DEC PDP-11/70. I still have a wirewrap tool.
I was wondering how the wires got wrapped like that. For some unfashionable reason I just didn’t consider a dedicated tool.
Whenever I put an enormous amount of time into a project, only to to have someone point out how simple the solution was, my reply is always, "Well, I know that NOW." Which means at the beginning, we don't know, and that's what makes it a journey. Have to say, though, your persistence is admirable. I have been there so many times myself, something that draws me to these videos. Glad you got the result in the end!
I’ve best to preempt the ‘you shud ov...’ crowd. However if my previous experiences are anything to go by then it won’t have worked. The other day someone wrote ‘You are a idiot’. I replied ‘It’s _an_ idiot’.
Truly enjoyed the video, I have the utmost respect for anyone trying to repair/restore any piece of technology/tools/etc. I can say that I've learned something from your video (where to spray deoxit in a potentiometer) Thanks!
Really solid chassis on this machine, even the inside looked in good nick.
I can definitely try to repair something similar for You next time, this can be an opportunity to make a very interesting video for me, and for you will be free of any charge
If the board unplugged I’d be more than happy to send it over - I think that would have been interesting.
I love this sort of video because it's the sort of thing I enjoy doing myself. I'm currently "umming and arring" over this: is.gd/AmpexVPR but it's almost certainly way beyond my capabilities unless I strike very lucky. I have a mate with a load of 1" Ampex videotapes he'd love to archive but there are no machines. I'm tempted to have a go. I applaud your tenacity, Mat, you're a lot better at repairing things than you think!
Old ‘untested’ video equipment is a definite no-go for me. I’ve seen so many ‘in need of repair’ players on ebay - and then when I look at the sellers other listings it’s clear they repair electronics for a living. I just think to myself if they can’t fix them then what hope do I have.
On the flipside, it could have been the auto-stop circuiy was going the other way and stopping the tape after a few seconds. Obviously the simple fix is remove the solenoid wire but still would have been frustating. I repaired one of these style units as a kid (and scrapped many similar units for motors, lights and those cool flywheels)
I considered that too - the fact that it wasn’t engaging all the time made me feel that the sensor must be working and perhaps the fault was further down the line. Turns out though that I was sort-of right but for the wrong reasons.
Very well done. I can see that your skills are maybe a touch above mine, but that’s never stopped me from disassembling something. I still have a Bang & Olufsen deck taken apart on my bench from a year ago. Just the d$&# dust cover mounts are over complicated. Why not start with something easy, like a B&O product? You’ve also touched on the issue of finding the correct belts. A quick look around Tapeheads or AudioKarma and you’ll see that over here, there’s someone who seems to have every belt for every machine, but once you order them, you start a process similar to negotiating nuclear arms reductions with a pack of wolves. Maybe the ones who were busy not raising you. In the end, you have no belts and a ragged bottom. Edit: One last thing. I’m of an age where I take several daily meds. I save empty prescription bottles for projects where I can put the screws and small bits in to save them. I take so many pills that I have an abundant supply.
Great job. You’ve inspired me to have a go at my Yamaha tape deck which has a similar wow problem. Hopefully replacing the rubbery bits will fix it.
Fantastic, Mat! If I were wearing a hat, I'd take it off to you right now. Your perseverance really paid off. I wonder if the handy clip for holding up the eject mechanism was actually needed whilst the machine was being assembled rather than incredible foresight for future repairers? Whatever, you not only managed the repairs, but also to make an interesting video about the process. Good show indeed! Have a great weekend.
Very enjoyable! :D
Absolutely brilliant video , really shows the struggle that people like me face doing repairs , when people ask me why I still have There equipment 2 months later I’ll show them this video , ps your the e clip king
I'm sending you my old Pioneer dual cassette player. Even my repair shop's best fingers gave up and sent it back in bits, but you appear to have mastered the art of fixing the unfixable :) Love your work - wish I had half your patience and a fraction of your video skills.
Who needs a full auto-stop mechanism when you can play around with these inviting little levers. Well done, sir!
Excellent video as always so much information! Vintage gear is getting had to come by especially someone who can fix it these days in a disposable world!
It’s a great looking deck. Love the illuminated view at the end. You have more patience than me!
When I can get in contact with my Ex Engineer Mat I will show him the circuit diagram and see if he can figure it out. Looking at the large diode and regulator transistor, it might be that the transistors drive the circuit to with the power to the solenoid. I'm not an expert but I would try checking the transistors on the board.
Another day made better by a video that was just about messing around with cool technology. Can't say more than it was an enjoyable video. Keep making them. I look forward to every Patreon notice of one of your videos.
Enjoyed the video very much.
I bought a Sony portable cassette/radio from 1977 the other day (as old as me!) and had a very similar crackly experience from the buttons. Rather peeved as it was sold as "good working order". I was recommended some switch cleaner, so I'm letting it all dry til tomorrow and we'll see if my first repair job (I've given up on the CED for now!) is any good!
So turns out I hadn't sprayed the potentiometer, as I wasn't really aware of what one was! Rectified now! Thank you! I've learnt something there!
Ah dammit Matt. I skipped out on replacing the bulbs in my cassette bay because I couldn’t be bothered. You’ve shown me up now. Off to eBay I go. Anyhoo. Great video. I could sit and watch you do this all day. As for kicking yourself for not tracking down an equivalent service manual until it was too late....I believe you learn so much more doing it blind and experimenting and tinkering rather than just painting by numbers* *the exception being IKEA furniture. No person on earth can wing it with IKEA furniture. Crazy Swedish logic puzzles.
I have a similar blind-spot in my skill set. Mechanical stuff is "easy" because you can actually see what a part is supposed to do, or at least it's easy to visualize. But electronic components are enigmatic and require a degree of memorization and a flair for units of measurement to get past the learning curve. Indeed, this is what kept me from pursuing a career in audio engineering. In school, I did fine when it came to using the various pieces of studio tech, but when it came servicing... say, an equalizer, I could feel my brain switching off. I am sure this is a result of doing so poorly at math (or maths, as you lot say! Although, there's the whole "sports" vs "sport" difference that has always confounded me) when I was a lad. This is a very well-paced video. So your editing skills are top-notch!
You have Legos and Math and we have Lego and Maths - it all works out in the end. One S two words.
They always say hindsight is a wonderful thing! Well done for your persistence...
Thanks for your best video ever, Matt! For me it's the best one because it really hits the string with my own technical adventures and misadventures of the recent years. I can say that your videos took quite a noticeable part in encouraging me to learn how to repair old things and get into new professions. Three years ago I knew and could do probably only 1% of what I am able to do now, fix and create things. I am nearly 40 and I thought before that it's the age when person already barely learns anything new, and yet somehow I am learning now much quicker and more effectively than in my years at the university. I think your videos, as well as those by Adrian Black, Mr. Carlson, Big Clive, Shango066, Neil of RetroManCave and of course David the 8-bit Guy are indeed the best college one tech-minded person can ever have, no schools or universities needed, ha-ha!
Thanking you, find those type videos really interesting when someone has to troubleshoot without guides or manuals. Far more entertaining 🙂
Good length, and it doesn't drag. Thanks for the video!
Gah! MAT! Stop being so hard on yourself. So you went down a couple blind alleys (is that a thing people say over there?) and it took longer than you hoped. Big Whoop. *It's a 44 year old electro-mechanical device!!!* And you fixed it! In the end, you had a nicely rebuilt machine which, if you keep it, will serve you for years. Come to think of it ... it has VU meters and a flip clock so I *know* you will keep it. :-) Give yourself some credit - this was a great repair job that could not be duplicated by probably more than a few hundred people in all of the UK.
At least the clock worked. I once made the huge mistake of taking the top off a drum type digital clock in cooker because the motor was getting noisy. At that point various shafts got out of alignment, It took me tens of hours to get the thing telling the time again and I never did get the timer part working. The usual problem was things like getting to 19:59 then jamming because the end drum was in the wrong position. Regarding wirewrap I have seen that in a 1980s Sony record deck. Personally I spent an entire summer holiday in 1982 wirewrapping a board with about 120 ICs on it. When it worked they offered me a permanent position in the department when I finished Polytechnic.
I'd start at the transistor that engages the solenoid... it's probably that beefy one on the left side of the board. See if it grounds out when it's supposed to stop the tape.
How would I see if it grounds out - and what would that tell me?
Who doesn't love a happy ending.
My friend was trying to fix an old lawnmower I have and I told him, by the time you put the thing back together for the last time you'll be so good at it yet never need to do it again D: :P General skill level is one thing, but specific to an individual item is another :P
Interesting video, I like to see how all the mechanics are inside, this thing looks very well-built to me :-) About the electronics: probably not that difficult, as a lot is written down on the board. I could definitely give you some advice on that if you want. My basic tip: measure the voltage between the emitter (e) and base (b) connections of the transistors: it should be always about 0.5-0.7 volts, never more, then the transistor is broken. I'll have a look at the scheme at least, maybe I could find some most-probable-part-to-die there ;-)
My educated guess: C352 (the largest cap on the board) has degraded, and the voltage indicated at "stop the tape" cannot be reached, so it won't stop. Second option: the power transistor Q354 died, you could check that by putting a 10k resistor between the base of that transistor and the B+, the solenoid should then work. If this transistor is broken, I would also recommend to check the diode on the solenoid, if that is broken, it could be the reason for the power transistor to fail over time. But my first guess would be degraded capacitor C352.
Can't wait. I saw the brief preview of drilling. I had stripped a screw on my CT when replacing the belts and clutch. Fortunately I could use some pliers to break free. The drill was my backup.
Have you thought of a second channel with outtakes, ASMR, etc? I’d personally love to watch the 10 hours of futile repair attempts. Yes, I’m weird.
“I can’t get it in from any angle... I guess I have to drill it!” 😂
Your videos are never too long!