Wow... Just wow! My Dad had a GF9191 when I was an early teen (im 57 now). Remember taking this to bits about 25 years ago as the tape sounded wobbly. This floods back those days. So I got it to bits, took 1 look at the tape mech, cleaned what I could, put it all back together again and that was me done. It was a bit better. My Dad bought this from Hira House, Elizabeth St, Cheetham Hill, Manchester. They had a huge Sharp sign on yhe warehouse.(now Texet) and I think it was trade only, but his friend David Preece worked at Ameltone House nearby got it home with trade discount. Lovely piece of kit. Great sound and really good built in stereo mics. Sharp had a big presence on the 80s and had a big warehouse in Newton Heath, Manchester.
Another reason can be the disappearance of manufacturers: this morning I tried my Revox cassette player with Dolby B & C and now a playback amplifier inside has failed. The same channel already had recording limitations. Revox mechanics are still working fine (I once found a UK supplier for the capstan rollers and the rest is far from worn), but for electronics no manufacturer or repair specialist still survives. Studer Revox withdrew from consumer markets and many years I was warned on this inside the shop having a few million electronic parts in stock and now also gone from the market. Fortunately my very first deck, the Tandberg TCD300 still works, but it only has the Dolby B system to play my Dolby C recording with, not ideal of course. BTW Tandberg and their impeccable service organisation has gone too. Summing up: whether in boomboxes or in high end audio, manufacturers having gone are a problem too...
One thing stood out to me, it was HONEST!!! Good speakers , real tweeters , good cassette for the time, very good microphones, nothing pretending to be better than it was. It's still amazing to me that today you can buy the belts, wheels etc for a unit built in 1984! Great video, loved the panic at twice the speed try!
@@AnnaVannieuwenhuyse That's not quite the reason. These parts are available now because there's demand for them from the retro audio community, so some enthusiasts and the Chinese are producing these pinch rollers, idler tires and belts and gears. Most of these *were* standard parts, but they are not used anymore in todays electronics. Today, good quality flat belts in high quantities are only produced for turntables, and I can't think of anything else mass produced consumer electronics that uses belts, apart from the tray mechanism of CD/DVD/BD players. The belts, idler tires and gears in these high quality repair kits are being manufactured in low quantities in Slovakia, Hungary, Poland, maybe Germany and I guess probably also in the US. And you can also get the cheap but questionable quality ones from China. I think pinch rollers are only being made in China, some of them are of good quality, these European parts sellers source them from reliable Chinese producers and usually test them one by one prior to selling them. Chinese belts are not recommended, I tried multiple sources and usually 1 out of 10 produces bearable wow&flutter.
What I used to love about electronics from that era, is the plethora of Inputs/Outputs to experiment with. These days you're lucky to get a headphone socket.
Chain linking several not very good ’boxes, all with dodgy batteries, to make a mighty racket on the move was the true sound of the very early eighties.
100% agree. As a kid I had a Sony Beta VCR that had audio dubbing & video editing features and the back was plenty of I/O connectors. Those were fun times!
That's why I designed and built my own stereo with 8 inputs and 4 outputs. (Although, I forgot to put a headphone socket in there and it's too much trouble to unplug everything and install one. LOL)
Matt your confidence on repairing this stuff is so much improved. I remember years ago you were hesitant to open or touch anything, now you're ripping into this complex device without a worry.
Hi great repair ,I’ve got to tackle mine yet ,just working on a hitachi,the sharp gf 9191 was the boombox used in the clash rock the casbah,they only made it in silver and grey but in the video it’s red so it must have been custom painted,cheers Ade
It always amazes me how complicated the mechanisms are to make these cassette boomboxes work. so many gears, wheels, belts, and a mess of wires inside. Even though I grew up with cassettes, I do not miss them. I was very happy when optical media came around.
I had this very machine in 1979, I chose this because it had the phono input on the front. I used a garrard sp25 to play records with it. It had the most amazing sound quality. I would love one today. I bought it from my sisters littlewoods catalogue, couple of quid a week. The FM radio sounded good, it made great tapes, the loudness control gave it a good kick. I used to record the Adrian Juste show on radio 1 every week with this. Radio one went to FM at 1pm on a saturday for his show.
I rescued a GF-9191 and a GF-9494 many years ago. Both have the same problem as yours, on the 9494 the audio sometimes doesn't work on one channel. I will fix this someday. Great video sir.
@@adammcmichael4799 They’re all relatively simple internally, even the top end models. The first time I saw a JVC RCM 90 opened up, I was very surprised by how basic its innards were.
My version of a 'proper' 1970s radio cassette player was a Crown CSC-640F. I bought it when I worked at a hi-fi store and the salesman let me have it wholesale, so I paid something like £80 for it instead of £130, which was a lot of money in 1978. I had it for about twenty years and I absolutely loved it. First the cassette mechanism packed in and then the switches on the top stopped working so I eventually binned it but it went everywhere with me as I moved around different parts of the country and it is still probably the nicest piece of audio equipment I have ever owned.
If you think this “takes the biscuit” you should see the late 70s Nakamichi classic 2 head transport mechanisms. I repaired 3 of them about 8 years ago and there were zero tutorial videos. I didn’t record it unfortunately. Most amazingly, however, there are STILL zero videos out there. Nakamichi complexity is off the charts and it has set the baseline for me in terms of patience and effort.
What a good example of old-time outstanding engineering and craftmanship. 40 years ago they weren't scared to complicate things to make perfect function and great ease of use.
I got myself an old Oral B Pulsonic Slim toothbrush, the battery needs replacing, well I use it for cleaning small things, it's not a miracle tool though.
Given the title, I thought defeat was indeed going to be snatched from the jaws of victory at the last moment! With your videos it’s never a given that there is success at the end, but it’s always the journey which makes it worth watching. Fascinating as ever, any kind of repair like this is great to see in its un-glorified form, disinterred belts and all!
I sometimes repair film cameras, and a trick I learned to make the plastics look good to great is to use car plastic polish. It helps quite a lot, especially with the matting.
This past summer I did some similar work on a 1975 Sharp GF-4000 and that thing is a beast being a mono-box! Very fun to work on, replaced the belts following a speed adjustment and a thorough clean out. The sound is fantastic and it also has an early version of that APSS-gadget. I will, however, need to do a recap on it at some point as it tends to loose power when doing more than just playing a cassette or the radio (recording off the radio for instance). But it's a fun machine and considering me and the GF-4000 are about the same age, one of us are in better condition - and it ain't me 😀
Something else to make people feel old. Free as a bird by The Beatles was released in 1995, now 28 years ago. In 1995 The Beatles had been split up for 25 years....
Great video as usual! I often repair cassette mechanisms, record players, and anything with belts. What I’ve found is that the belts we buy nowadays are sometimes already worn out and defective. I tend to be very cautious now when buying ‘new’ belts...
For times when you have a million different screws all different sizes just get a piece of cardboard and draw the shape of the think you are taking apart on it with a marker and make circles where the screws go, then as you remove a screw push it through the cardboard.
I use Sharpie markers. A mark next to each hole and on the screw. Learned that trick doing recall circuit boards in Honda stereo/ nav headunits years ago. So many screws in those things, almost none of them the same.
I was thinking the same thing. Since all the broken parts were still inside rolling around, it would be fairly simple to match the chunks to the posts they came from and superglue them back together. Also wish he had plugged a turntable into those front jacks.
I have a sharp gf9494 that i picked up at a garge sale some years ago for next to nothing. It's impressive as is, but needs this treatment too. Thanks for the video!
You did miss out a key point of lubrication - the capstan bearing would have most certainly needed some oil after it got covered with all that gunk and then cleaned up. The motor bearings would also benefit from some lubrication. Both of these parts being lubricated should help the W&F.
I would have to confirm by watching the video again, but I think I remember seeing a pop-up note in the lower right corner that he said he lubricated everything he just didn't show himself lubricating the moving parts. It was already a very long video for his typical length videos. Anyway perhaps when you have time you can watch it again and look for said pop-up in the right lower corner 😊.
ABS plastic is so easy to repair all it takes is acetone and it melts back together. I used this trick to repair motorcycle fairings. Melt some scrap abs in acetone to make putty to fill missing bits.
I really enjoyed this video , my older brother had the sharp GF8989 back in the 80,s and I wasn’t allowed to touch it, I always wanted to take it apart to see how it worked ha ha!
I watched the entire video, and as I suspected, the mechanics have a lot of fluctuations. In fact, I went crazy trying to get it to work properly! It’s still possible to achieve perfect functionality, but you need to adjust the front panel closure and make other various tweaks. I also had to replace the playback/recording head. Anyway, a great job was done in this video as well! Compliments.
Made in Japan & good quality back then unlike China today. You may need to check the speed on the deck also. If you fast foreword & rewind a few times on a c-90 tape it will break in the belts & help that wow & flutter a bit. Nice job Mat -Cheers!
Agreed and I think this is where his problem is, leaving it playing for a few hours will settle the tires and pinch roller also that tire on the capstan may be binding. All in all a good effort they usually need a second fettle.
Because of that rubber tube and how hard it is to clean and replace I now avoid Sharp cassette decks and boomboxes from the late 70s to mid 80s. Unfortunately they seemed to use that type of rubber tube and idler combination in pretty much all their cassette mechanisms for over a decade. It was repairing a cassette deck with that combination that resulted in much swearing, a lost weekend and me vowing never to touch another Sharp tape mechanism ever again. I did get it repaired and all the belts changed but it has similar wow and flutter issues to your boombox, I suspect one of the reasons is just that the rubber tubing isn't specially made to very tight tolerances today but is just a bit of smaller rubber tube cut to size.
I'm still repairing cassette decks professionally and I agree with your sentiments about Sharp cassette mechanisms with the rubber drive inside the capstan assembly. I've had to deal with a number of the home stereo cassette decks in the past year and every one of them required the rubber drive to be replaced. There's a seller on evilBay who has the correct rubber tube that is the correct length and machined to proper tolerances along with a replacement tyre for the idler wheel.
I repaired a GF-8585 and I couldn't get it working with lego pneumatic tube so I stuck other small tube from a headlight washer on it and it works perfectly. Also I remember that on this model the housing for the capstan idler could be removed for easier cleaning
I was wondering if you’ve ever seen a Sanyo dynamic sound 3000. It’s a PA system with a cassette and the 3500 I believe has an AM/FM radio as well. Those things were great back in the 80s. A RadioShack near me, sold three to a school for the PA system. And I bought two because the first one I wore out the cassette Player lol. It had a special hexagon speaker shape where the back of it had holes for Air flow for some serious base.
Matt, great video, I’m sure you are way ahead of me in this one but I noticed the capstan flywheel didn’t have completely free movement after cleaning with that tubing in place. I wonder if that is somehow not quite the same diameter as factory and is creating resistance to the capstan movement. Very nice work and great looking piece!
MAN that Thing is AWESOME!!! would have KILLED for one like that when i was growing up, Glad you saved it, this repair has made me relieved I never had to do that repair
Matt you have no idea how exited I got when I saw the "WIDE STEREO" function on this model. I used to have a Hitachi with the same function which I used on mix tapes to great effect. I'll be looking out for one ofe these myself now.
"Wide stereo" switches typically use "mid-side" processing to achieve this. Or, they "subtract" a little of each channel's output from the opposite channel. Later types would incorporate a slight delay between channels to (allegedly) enhance the effect. Personally, I've always *hated* the "wide" sound. Reminds me too much of those awful "electronically processed stereo" LPs which converted perfectly decent mono recordings into an echo-y, out of phase, unlistenable mess of a stereo image.
The go-to with any stereo cassette recorder of the era was the all-purpose DIN socket and whether it was any good when recording from a record player. Back then, that was top priority as I would often record any new LPs as soon as I got them, then played the tape rather than risk scratching the record/have it deteriorate with progressive plays. C90's were a must, then, so you could fit one album each side of a cassette. From the look and sound of this one, it would have been a good contender.
@@Tim091 Maube you could clear up an ancient question for me: I had an ITT stereo radio and a Japanese cassette deck when I was a kid around 1979. The radio had a DIN socket, the deck had phonos; connecting them for recording produced lower recording levels than optimum. Would that be some kind of impedance mismatch between the two?
Wow... You have serious patience... And lack of "Murphy 's interferance"... I know if I was doing this there would be several times a spring would go, "boingg" and id be on the floor, looking for them for an hour... But there is so much satisfaction in getting things back working
I havent seen the video yet, but its easy to repair the issue with the capstan drive. Use a piece of lego pneumatic hose, for the idler try to find a rubber seal in the sanitary area in your hardware store. I hope this helps someone. The motorspeed is setted with some wights in the inside, not easy to set them, i try to replace the motor with one that has a pot... Edit: Its also easy to do a line in mod. The phono- preamp is just wired to the board, input and output, resolder the cinch wires on the board and also the output from that preamp. A purple and another wire are directly soldered to the phono switch - delolder them on the phono amp side. The volume level is a a bit high, with a pot, or some resistors (voltage divider!) you can set it to a normal level of your smartphone or mp3 player, ive done this with mine and works fine (-:
Agreed, but one needs to take care that the pipe cleaner doesn't "shed" any of the "fluff," especially if used dry. I've had problems with that in the past. 🙁
Wee tip, if you can glue the pedestal posts parts back in again, put a bit of shrink tubing over it to add strength without adding width that may be a problem.
Agreed - or use Sugru instead of the shrink tubing, which has the advantage of filling in any small gaps. But definitely re-use the parts that have broken off!
I was very impressed that the Sugru repair worked at all!, … the original plastic looks like it was most likely a Polystyrene … which does degrade over time. Personally, I suspect someone had previously opened the thing up to try and fix the tape … quickly given up and then not been careful enough when refitting the screws … you have to remember the original holes were simply blank pilot holes and the screws are self-tapping … it’s very easy to cross thread them when replacing them. In addition, the strength of the plastic will have aged such that the threads will easily strip and the posts will burst apart (as seen!) if over tightened. Getting a good adhesive bond to this degraded polystyrene is difficult … surfaces need to be really clean (need to thoroughly degrease with IPA), lightly abrade to roughen up any smooth surfaces … another IPA wash and choose a good epoxy based system to mould the new posts. I wouldn’t recommend using the broken bits as they will still turn to dust when you try screwing into them … the threads will simply strip out. I think the best option would be to create simple moulds to reproduce the largest diameter of post possible (10mm ??) centred on each stump, then pot the mould to build a solid post of epoxy (5 minute Araldite should be ok if you’re impatient) … let the epoxy cure, then drill out new pilot holes and grind down the tops of each post to the correct height. Bit of a palaver .. but more robust. An alternative to standard epoxy adhesive would be something like Plastic Padding … which is an epoxy adhesive with a filler compound mixed in (gives it the grey colour) … but I’m not sure how good it would be at bonding to the Polystyrene .. 🤔
It’s really concerning that I rarely get any ad before or during ur videos , Matt , it is a good thing for me to have no ads on my favorite vintage stuff channel but it means ur channel is not being favored by the algorithm to run ads on.
Sometimes tape speed wobble is caused from not enough pressure on the capstan & pinch roller. Re check it & also alcohol both the capstan & pinch roller to eliminate any oils from your fingers or the bearings.
For anything that has a texturized surface like the cassette deck buttons, I would really recommend a decommissioned toothbrush. They are GODSENT for cleaning tiny nooks and crannies!
I have the GF-9090 from 1976 (very similar looking machine), which is also due a belt service. It can be seen at the end of my Studio Revamp video if you're interested.
On the wow/flatter issue, you should try just pressing play with no tape loaded, and let it just run for a few hours. In my experience with cassette players, if they haven't been run in many decades they tend to struggle as they find their stride again. May also need a good demagnetize.
@@Andy-fd5fg Just be careful about the oil you use. As others here have said, some light oils (like 3-in-1) contain compounds which can "soften" some of the plastics.
I believe the second hole next to the mike is an additional connector for a switch that you have on the mic that can be used to control recording. I remember an old LP/tape/radio system I had as a kid that had a connector like that.
Great episode. That was a lot of work! Loved watching. I bought a sharp GF 8989 on eBay recently. It seems better than this model. Soft touch buttons, Dolby, soft eject etc. Tweeters are out on mine.
Wow! Always enjoy your videos but this one represents something of a pinnacle for me! Close to a cautionary tale for sure but also a fitting testimony to those who can be bothered! Cheers! ❤
I have one of these, it's a great stereo, my advice would be to use an FM transmitter box plugged into your phone or such like, and listen through radio ,you might be surprised at the sound quality....peace
Great video. Looks like the plastic where the pinch roller axle is mounted at 26.27 is cracked. Also, wouldn't it have been easier to pop out on of those brass bearings to get that rubber tube in place?
12:36 Blowing out some fluff! Fantastic video! I couldn’t do a complex repair like this. I don’t have the patience nor the nimbleness to do all these steps. It’s amazing though that people used to carry these heavy beasts everywhere back in the 80’s.
Ever since seeing a mechanic do it I've started using multicolored paint markers to tag connectors and fasteners that are ambiguous. Super quick and I don't consider little paint dots with purpose to be any sort of substantial vandalism, and also very easy to remove with iso if you don't want to leave any trace.
@17:50 I see the massive rubber gunk on the wheel under the black gear. I think the wheel touches the rubber wheel and was transferred the gunk on to it. It may be contributing to the wobbliness.
With the wobbliness, I think it might be the idler tyre, which wasn't in your replacement kit. And it pretty east to change, compared to everything else you've already done. As you know it's the capstan (with it's big heavy flywheel for stability) which gets the tape pressed against it by the pinch roller which actually pulls the tape through as a consistent speed. But that idler tyre is running off the piece you changed and taking up the slack in the tape. I'd say that's where your wobble is coming from.
Hi Matt, another smashing Saturday morning video treat. Instead of using your screwdriver to keep the screw-holes patent while rebuilding them with Sugru would it have been better to use the screws themselves. You could lightly oil them to ensure the Sugru does stick to it and the screws would create their own internal thread as you build-up the pegs.
Was thinking the same thing, I used to occasionally use a 2 part rawl plug putty and would put the screw in when the putty was soft to create a thread then take it out as the putty firmed up a little, then re-attach with whatever I was trying to fix to the wall once the putty was fully hard.
Agreed. I would also have used liquid poly to re-attach the "rattling parts" before doing the Sugru build-up. FYI: I used Sugru some years ago to "mod" the cover plate for an iron (as in: for ironing clothes!) so that it didn't fall off. Several years on … it's still going strong and showing no signs of wear, going soft, or any other problems. 😉
Excellent work from Techmoan i think 👍 I would of given up once i saw one of the screws fall out :D It looked EXCELLENT once all cleaned up to 😎 + it's AMAZING how they make all these things in the past & nowadays(MIND-BOGGLING for my little mind) :D
Wow... Just wow! My Dad had a GF9191 when I was an early teen (im 57 now). Remember taking this to bits about 25 years ago as the tape sounded wobbly. This floods back those days. So I got it to bits, took 1 look at the tape mech, cleaned what I could, put it all back together again and that was me done. It was a bit better. My Dad bought this from Hira House, Elizabeth St, Cheetham Hill, Manchester. They had a huge Sharp sign on yhe warehouse.(now Texet) and I think it was trade only, but his friend David Preece worked at Ameltone House nearby got it home with trade discount. Lovely piece of kit. Great sound and really good built in stereo mics. Sharp had a big presence on the 80s and had a big warehouse in Newton Heath, Manchester.
Another reason can be the disappearance of manufacturers: this morning I tried my Revox cassette player with Dolby B & C and now a playback amplifier inside has failed. The same channel already had recording limitations. Revox mechanics are still working fine (I once found a UK supplier for the capstan rollers and the rest is far from worn), but for electronics no manufacturer or repair specialist still survives. Studer Revox withdrew from consumer markets and many years I was warned on this inside the shop having a few million electronic parts in stock and now also gone from the market. Fortunately my very first deck, the Tandberg TCD300 still works, but it only has the Dolby B system to play my Dolby C recording with, not ideal of course. BTW Tandberg and their impeccable service organisation has gone too. Summing up: whether in boomboxes or in high end audio, manufacturers having gone are a problem too...
I have no interest in owning a cassette boom box yet I happily watched this from start to end. Thanks for the diversions
One thing stood out to me, it was HONEST!!! Good speakers , real tweeters , good cassette for the time, very good microphones, nothing pretending to be better than it was. It's still amazing to me that today you can buy the belts, wheels etc for a unit built in 1984! Great video, loved the panic at twice the speed try!
You can buy the belts and wheels because they're fairly standard parts. That's a great thing!
@@AnnaVannieuwenhuyse That's not quite the reason. These parts are available now because there's demand for them from the retro audio community, so some enthusiasts and the Chinese are producing these pinch rollers, idler tires and belts and gears. Most of these *were* standard parts, but they are not used anymore in todays electronics. Today, good quality flat belts in high quantities are only produced for turntables, and I can't think of anything else mass produced consumer electronics that uses belts, apart from the tray mechanism of CD/DVD/BD players.
The belts, idler tires and gears in these high quality repair kits are being manufactured in low quantities in Slovakia, Hungary, Poland, maybe Germany and I guess probably also in the US. And you can also get the cheap but questionable quality ones from China. I think pinch rollers are only being made in China, some of them are of good quality, these European parts sellers source them from reliable Chinese producers and usually test them one by one prior to selling them. Chinese belts are not recommended, I tried multiple sources and usually 1 out of 10 produces bearable wow&flutter.
@@mrnmrn1 small belts are still used in devices made today, so they are in demand because they are being used. And if it exists, why not use it?
Way ahead of amstrad junk
@@AnnaVannieuwenhuyse Yes, that's what I said. Tray mechanism of CD/DVD/BD players. I can't come up with anything else that uses belts nowadays.
What I used to love about electronics from that era, is the plethora of Inputs/Outputs to experiment with. These days you're lucky to get a headphone socket.
Chain linking several not very good ’boxes, all with dodgy batteries, to make a mighty racket on the move was the true sound of the very early eighties.
True
100% agree. As a kid I had a Sony Beta VCR that had audio dubbing & video editing features and the back was plenty of I/O connectors. Those were fun times!
That's why I designed and built my own stereo with 8 inputs and 4 outputs.
(Although, I forgot to put a headphone socket in there and it's too much trouble to unplug everything and install one. LOL)
@@AseGarciaYeah, they were. When I was a kid I made videos of like NES gameplay with an audio mixer and dubbed in music and narration and stuff lol.
Matt your confidence on repairing this stuff is so much improved. I remember years ago you were hesitant to open or touch anything, now you're ripping into this complex device without a worry.
Exactly my thoughts. He used to say "I don't do repairs, just some minor touchups" but look at him now! Really awesome to see
Agreed! If that were me that tape deck would have never gone back together 😂
Mend it Matt
@@DjZelous ... but without Mark's awesome workshop and decades of experience!
Hi great repair ,I’ve got to tackle mine yet ,just working on a hitachi,the sharp gf 9191 was the boombox used in the clash rock the casbah,they only made it in silver and grey but in the video it’s red so it must have been custom painted,cheers Ade
Nasty flutter was a trademark of those mid-1980's ghetto blasters, even when they were brand new. Fun video, Techmoan!
The 70's and 80's has to be the most creative period of design in electronics and cars.
Always enjoy your videos
42:39 - you just can't get away from this lie
Too true!
I love these repair/restoration videos. They are quite handy as I'm learning how to repair old stereo equipment myself.
It always amazes me how complicated the mechanisms are to make these cassette boomboxes work. so many gears, wheels, belts, and a mess of wires inside. Even though I grew up with cassettes, I do not miss them. I was very happy when optical media came around.
I had this very machine in 1979, I chose this because it had the phono input on the front. I used a garrard sp25 to play records with it. It had the most amazing sound quality. I would love one today. I bought it from my sisters littlewoods catalogue, couple of quid a week. The FM radio sounded good, it made great tapes, the loudness control gave it a good kick. I used to record the Adrian Juste show on radio 1 every week with this. Radio one went to FM at 1pm on a saturday for his show.
I had the GF8585 around the same time, great sound qulity
Very uncommon but indeed useful to have a phono properly plugged in 😊
What I'd like to know is if there was a Sharp portable phonograph designed specifically for this boombox
An am station switched to FM for one program?
@@taxirob2248lol probably not. But i don't know what that would have looked like. A record player doesn't really care what you plug it into.
I rescued a GF-9191 and a GF-9494 many years ago. Both have the same problem as yours, on the 9494 the audio sometimes doesn't work on one channel. I will fix this someday. Great video sir.
The complexity is eye watering. I can't imagine the assembly line.
I think a lot of the assembly was automated
A lot of that automation is lost technology now
@@qlue7881 … nope. Apart from the circuit board printing, these units were entirely assembled by hand.
This boombox is actually quite simple internally compared to many others, and there was never any automation in the assembly of boomboxes
@@adammcmichael4799 They’re all relatively simple internally, even the top end models. The first time I saw a JVC RCM 90 opened up, I was very surprised by how basic its innards were.
I assume when you would be working the line for 12 hours a day it would become much simpler than it looks
My version of a 'proper' 1970s radio cassette player was a Crown CSC-640F. I bought it when I worked at a hi-fi store and the salesman let me have it wholesale, so I paid something like £80 for it instead of £130, which was a lot of money in 1978. I had it for about twenty years and I absolutely loved it. First the cassette mechanism packed in and then the switches on the top stopped working so I eventually binned it but it went everywhere with me as I moved around different parts of the country and it is still probably the nicest piece of audio equipment I have ever owned.
This is a treat from my youth from my grade school days
If you think this “takes the biscuit” you should see the late 70s Nakamichi classic 2 head transport mechanisms. I repaired 3 of them about 8 years ago and there were zero tutorial videos. I didn’t record it unfortunately. Most amazingly, however, there are STILL zero videos out there. Nakamichi complexity is off the charts and it has set the baseline for me in terms of patience and effort.
50mins of Techmoan! What a treat - my weekend is complete.
Good gosh, it is! Been happily watching not even paying attention that it’s been near an hour.
Best techmoan channel ever!!
good job. fixing that tape mech was the most satisfying thing ive seen all day.
Techmoan does the best vids ever on tech!!
What a good example of old-time outstanding engineering and craftmanship. 40 years ago they weren't scared to complicate things to make perfect function and great ease of use.
Great video, enjoyed watching it, thanks mate!
I have a few cassette mechanisms that I want to refurbish soon and things like this give me some confidence to do it. Thanks!
Toothbrushes are ace for cleaning the buttons and textured metal. I always have them in the cleaning kit.
never throw out old toothbrushes!
I got myself an old Oral B Pulsonic Slim toothbrush, the battery needs replacing, well I use it for cleaning small things, it's not a miracle tool though.
Also used interdental brushes would've been great for cleaning that gunked up capstan hole.
@@YS_Production Yes, using all those sticks seemed a bit of a waste to me.
Also paint brushes for more gentle cleaning.
Given the title, I thought defeat was indeed going to be snatched from the jaws of victory at the last moment! With your videos it’s never a given that there is success at the end, but it’s always the journey which makes it worth watching. Fascinating as ever, any kind of repair like this is great to see in its un-glorified form, disinterred belts and all!
"The rattling sound is a bit of a concern"
A promising start haha
The exasperated sigh when he first tipped it was a mood.
I read that in Blackadder's voice
When the screws fell out, I heard DankPods voice in my head saying, "Someone's been in 'ere!"
Cars, electronics, packages in the mail containing glass... three things where I've said the same thing.
I sometimes repair film cameras, and a trick I learned to make the plastics look good to great is to use car plastic polish. It helps quite a lot, especially with the matting.
This past summer I did some similar work on a 1975 Sharp GF-4000 and that thing is a beast being a mono-box! Very fun to work on, replaced the belts following a speed adjustment and a thorough clean out. The sound is fantastic and it also has an early version of that APSS-gadget. I will, however, need to do a recap on it at some point as it tends to loose power when doing more than just playing a cassette or the radio (recording off the radio for instance). But it's a fun machine and considering me and the GF-4000 are about the same age, one of us are in better condition - and it ain't me 😀
This is an amazing amount of knowledge. Thank you.
40 years old...
40 years before this was made was the end of WW2..
I only say that to make myself feel old. Carry on.
Something else to make people feel old.
Free as a bird by The Beatles was released in 1995, now 28 years ago. In 1995 The Beatles had been split up for 25 years....
Almost to the day to boot!
That’s cheered me up no end!
29:56 that date on the motor. That's the day I was born, My birthday. Thank you. 😃😃
Great video as usual! I often repair cassette mechanisms, record players, and anything with belts. What I’ve found is that the belts we buy nowadays are sometimes already worn out and defective. I tend to be very cautious now when buying ‘new’ belts...
The problem is probably that the new belts are not manufactured to tight tolerances.
nice work in restoring it
For times when you have a million different screws all different sizes just get a piece of cardboard and draw the shape of the think you are taking apart on it with a marker and make circles where the screws go, then as you remove a screw push it through the cardboard.
I use Sharpie markers. A mark next to each hole and on the screw. Learned that trick doing recall circuit boards in Honda stereo/ nav headunits years ago. So many screws in those things, almost none of them the same.
I have one of these...Perfect working order but has a few battle scars... Proper old skool boombox...10 D...
For the plastic standoffs that you have still parts left,you can reconstruct them with super glue and baking soda
It is very quick to cure also!
I was thinking the same thing. Since all the broken parts were still inside rolling around, it would be fairly simple to match the chunks to the posts they came from and superglue them back together. Also wish he had plugged a turntable into those front jacks.
I have a sharp gf9494 that i picked up at a garge sale some years ago for next to nothing. It's impressive as is, but needs this treatment too. Thanks for the video!
You did miss out a key point of lubrication - the capstan bearing would have most certainly needed some oil after it got covered with all that gunk and then cleaned up. The motor bearings would also benefit from some lubrication. Both of these parts being lubricated should help the W&F.
I would have to confirm by watching the video again, but I think I remember seeing a pop-up note in the lower right corner that he said he lubricated everything he just didn't show himself lubricating the moving parts. It was already a very long video for his typical length videos. Anyway perhaps when you have time you can watch it again and look for said pop-up in the right lower corner 😊.
ABS plastic is so easy to repair all it takes is acetone and it melts back together. I used this trick to repair motorcycle fairings. Melt some scrap abs in acetone to make putty to fill missing bits.
Brilliant as usual! Better than anything the BBC put out.
I really enjoyed this video , my older brother had the sharp GF8989 back in the 80,s and I wasn’t allowed to touch it, I always wanted to take it apart to see how it worked ha ha!
I watched the entire video, and as I suspected, the mechanics have a lot of fluctuations. In fact, I went crazy trying to get it to work properly! It’s still possible to achieve perfect functionality, but you need to adjust the front panel closure and make other various tweaks. I also had to replace the playback/recording head. Anyway, a great job was done in this video as well! Compliments.
Made in Japan & good quality back then unlike China today. You may need to check the speed on the deck also. If you fast foreword & rewind a few times on a c-90 tape it will break in the belts & help that wow & flutter a bit. Nice job Mat -Cheers!
Excellent video and great repair! I think what went wrong with it playing too fast was that the pinch roller wasn't engaging with the capstan.
Agreed and I think this is where his problem is, leaving it playing for a few hours will settle the tires and pinch roller also that tire on the capstan may be binding. All in all a good effort they usually need a second fettle.
I had to do the capstan drive tyre on my one it was the classic take-up spool not turning issue. I used silicone rubber tube as a new tyre.
Because of that rubber tube and how hard it is to clean and replace I now avoid Sharp cassette decks and boomboxes from the late 70s to mid 80s. Unfortunately they seemed to use that type of rubber tube and idler combination in pretty much all their cassette mechanisms for over a decade. It was repairing a cassette deck with that combination that resulted in much swearing, a lost weekend and me vowing never to touch another Sharp tape mechanism ever again. I did get it repaired and all the belts changed but it has similar wow and flutter issues to your boombox, I suspect one of the reasons is just that the rubber tubing isn't specially made to very tight tolerances today but is just a bit of smaller rubber tube cut to size.
Im using lego- pneumatic tubes for this, works well (-:
Yes, it's the rubber tubing that is the weak link. It's out of round. Just need to find something from another device that uses high precision rubber.
I'm still repairing cassette decks professionally and I agree with your sentiments about Sharp cassette mechanisms with the rubber drive inside the capstan assembly. I've had to deal with a number of the home stereo cassette decks in the past year and every one of them required the rubber drive to be replaced. There's a seller on evilBay who has the correct rubber tube that is the correct length and machined to proper tolerances along with a replacement tyre for the idler wheel.
I repaired a GF-8585 and I couldn't get it working with lego pneumatic tube so I stuck other small tube from a headlight washer on it and it works perfectly. Also I remember that on this model the housing for the capstan idler could be removed for easier cleaning
I was wondering if you’ve ever seen a Sanyo dynamic sound 3000. It’s a PA system with a cassette and the 3500 I believe has an AM/FM radio as well. Those things were great back in the 80s. A RadioShack near me, sold three to a school for the PA system. And I bought two because the first one I wore out the cassette Player lol. It had a special hexagon speaker shape where the back of it had holes for Air flow for some serious base.
Matt, great video, I’m sure you are way ahead of me in this one but I noticed the capstan flywheel didn’t have completely free movement after cleaning with that tubing in place. I wonder if that is somehow not quite the same diameter as factory and is creating resistance to the capstan movement. Very nice work and great looking piece!
Great video to watch 👍
These were impressive complex electromechanics!
Just compare this with a smartphone and a Bluetooth speaker.
30:00 4 days from now, that motor will be 40 years old!
Just missed it 😂
Got to sort my sharp gf9500 getting no record. Logic servo deck.dam complicated.great job sir
Hello from the cheep seats
Loved my 9191
MAN that Thing is AWESOME!!! would have KILLED for one like that when i was growing up, Glad you saved it, this repair has made me relieved I never had to do that repair
Thank you for not stopping on Rod Stewart.
Matt you have no idea how exited I got when I saw the "WIDE STEREO" function on this model. I used to have a Hitachi with the same function which I used on mix tapes to great effect. I'll be looking out for one ofe these myself now.
"Wide stereo" switches typically use "mid-side" processing to achieve this. Or, they "subtract" a little of each channel's output from the opposite channel. Later types would incorporate a slight delay between channels to (allegedly) enhance the effect.
Personally, I've always *hated* the "wide" sound. Reminds me too much of those awful "electronically processed stereo" LPs which converted perfectly decent mono recordings into an echo-y, out of phase, unlistenable mess of a stereo image.
@caddelworth Thanks for the info, much appreciated.
works really good considering the age nice restoration
49 minutes!!! Now we're talking 👏👏👏
I mentioned it before, I like the new camera, you look great 👍🏼😃
The go-to with any stereo cassette recorder of the era was the all-purpose DIN socket and whether it was any good when recording from a record player. Back then, that was top priority as I would often record any new LPs as soon as I got them, then played the tape rather than risk scratching the record/have it deteriorate with progressive plays. C90's were a must, then, so you could fit one album each side of a cassette. From the look and sound of this one, it would have been a good contender.
I standardized on C60, and just left out the tracks I loved the least.
Yep. many's the 'five-pin DIN to two phono' cable I soldered up back in the day.
@@Tim091 Maube you could clear up an ancient question for me: I had an ITT stereo radio and a Japanese cassette deck when I was a kid around 1979. The radio had a DIN socket, the deck had phonos; connecting them for recording produced lower recording levels than optimum. Would that be some kind of impedance mismatch between the two?
Wow... You have serious patience... And lack of "Murphy 's interferance"... I know if I was doing this there would be several times a spring would go, "boingg" and id be on the floor, looking for them for an hour... But there is so much satisfaction in getting things back working
I havent seen the video yet, but its easy to repair the issue with the capstan drive. Use a piece of lego pneumatic hose, for the idler try to find a rubber seal in the sanitary area in your hardware store. I hope this helps someone.
The motorspeed is setted with some wights in the inside, not easy to set them, i try to replace the motor with one that has a pot...
Edit:
Its also easy to do a line in mod. The phono- preamp is just wired to the board, input and output, resolder the cinch wires on the board and also the output from that preamp. A purple and another wire are directly soldered to the phono switch - delolder them on the phono amp side.
The volume level is a a bit high, with a pot, or some resistors (voltage divider!) you can set it to a normal level of your smartphone or mp3 player, ive done this with mine and works fine (-:
For the cleaning of small holes i use pipe cleaners. They’re cheap and come in handy for almost everything.
Agreed, but one needs to take care that the pipe cleaner doesn't "shed" any of the "fluff," especially if used dry. I've had problems with that in the past. 🙁
That was quite a weekend project, I'm enjoying the video very much,thank you.
that was a good one - if you do revisit the transport may i say try the old pinch roller and a drop of oil in it
Wee tip, if you can glue the pedestal posts parts back in again, put a bit of shrink tubing over it to add strength without adding width that may be a problem.
Agreed - or use Sugru instead of the shrink tubing, which has the advantage of filling in any small gaps. But definitely re-use the parts that have broken off!
Personally would have glued the posts back together when possible and secured them with suitable size zip ties, they can take a lot of strain.
I was very impressed that the Sugru repair worked at all!, … the original plastic looks like it was most likely a Polystyrene … which does degrade over time. Personally, I suspect someone had previously opened the thing up to try and fix the tape … quickly given up and then not been careful enough when refitting the screws … you have to remember the original holes were simply blank pilot holes and the screws are self-tapping … it’s very easy to cross thread them when replacing them. In addition, the strength of the plastic will have aged such that the threads will easily strip and the posts will burst apart (as seen!) if over tightened.
Getting a good adhesive bond to this degraded polystyrene is difficult … surfaces need to be really clean (need to thoroughly degrease with IPA), lightly abrade to roughen up any smooth surfaces … another IPA wash and choose a good epoxy based system to mould the new posts. I wouldn’t recommend using the broken bits as they will still turn to dust when you try screwing into them … the threads will simply strip out. I think the best option would be to create simple moulds to reproduce the largest diameter of post possible (10mm ??) centred on each stump, then pot the mould to build a solid post of epoxy (5 minute Araldite should be ok if you’re impatient) … let the epoxy cure, then drill out new pilot holes and grind down the tops of each post to the correct height.
Bit of a palaver .. but more robust.
An alternative to standard epoxy adhesive would be something like Plastic Padding … which is an epoxy adhesive with a filler compound mixed in (gives it the grey colour) … but I’m not sure how good it would be at bonding to the Polystyrene .. 🤔
Thanks for the tip!
Fascinating, entertaining and informative. Top stuff.
It’s really concerning that I rarely get any ad before or during ur videos , Matt , it is a good thing for me to have no ads on my favorite vintage stuff channel
but it means ur channel is not being favored by the algorithm to run ads on.
use adblock and have 0 ads . if you want to support a youtuber you can use their program, they all have something
Here in Scotland, I definitely get ads. during and after Techmoan videos.
Sometimes tape speed wobble is caused from not enough pressure on the capstan & pinch roller.
Re check it & also alcohol both the capstan & pinch roller to eliminate any oils from your fingers or the bearings.
For anything that has a texturized surface like the cassette deck buttons, I would really recommend a decommissioned toothbrush. They are GODSENT for cleaning tiny nooks and crannies!
Even better still, an old head from an electric toothbrush!
Lol "decommissioned". I love reading the comments section of this channel.
...or your current one. Just be sure to get the food particles out of it first. 😬
I have the GF-9090 from 1976 (very similar looking machine), which is also due a belt service. It can be seen at the end of my Studio Revamp video if you're interested.
On the wow/flatter issue, you should try just pressing play with no tape loaded, and let it just run for a few hours. In my experience with cassette players, if they haven't been run in many decades they tend to struggle as they find their stride again.
May also need a good demagnetize.
a drop of fine machine oil on some moving parts on the mechanism would do some good too.
I expect any grease they used would have dried out by now.
@@Andy-fd5fg Yes! I have a little bottle of watch oil that everything i work on gets a treatment of.
@@Andy-fd5fg Just be careful about the oil you use. As others here have said, some light oils (like 3-in-1) contain compounds which can "soften" some of the plastics.
I believe the second hole next to the mike is an additional connector for a switch that you have on the mic that can be used to control recording.
I remember an old LP/tape/radio system I had as a kid that had a connector like that.
Haha, should have watched a few minutes longer 🙂
stoked to see a video this long from my favorite repair chap
Great episode. That was a lot of work! Loved watching. I bought a sharp GF 8989 on eBay recently. It seems better than this model. Soft touch buttons, Dolby, soft eject etc. Tweeters are out on mine.
The reason why it is so wobly is because your pinch roler isn`t pinching correctly.
Wow! Always enjoy your videos but this one represents something of a pinnacle for me! Close to a cautionary tale for sure but also a fitting testimony to those who can be bothered! Cheers! ❤
My parents owned a slightly later and cheaper version of this, even brand new the tape playback wasn't the greatest!
Interesting!
I have one of these, it's a great stereo, my advice would be to use an FM transmitter box plugged into your phone or such like, and listen through radio ,you might be surprised at the sound quality....peace
My first thought about you using Sugru was that it was going to be too soft to hold the structure. Epoxy putty would've been more suitable.
I was going to suggest the same. Epoxy putty, and using the original screws (with a smear of vaseline on the threads) to form around.
Once it's set, Sugru is *much* tougher than you'd imagine.
I was getting anxious about losing or breaking old plastic....... you are a brave soul!! (Mixed opinions... love the video, hate the anxiety!😅)
I love the fixes on this channel. You learn a lot of stuff. Love your videos mate! Greetings from Brazil! (it's 6am here also ;-) Great channel!
Excellent recondition.
This is peak Techmoan, amazing stuff
Great video.
Looks like the plastic where the pinch roller axle is mounted at 26.27 is cracked.
Also, wouldn't it have been easier to pop out on of those brass bearings to get that rubber tube in place?
12:36 Blowing out some fluff!
Fantastic video! I couldn’t do a complex repair like this.
I don’t have the patience nor the nimbleness to do all these steps.
It’s amazing though that people used to carry these heavy beasts everywhere back in the 80’s.
I very much enjoy the fixes. Well done.
Ever since seeing a mechanic do it I've started using multicolored paint markers to tag connectors and fasteners that are ambiguous. Super quick and I don't consider little paint dots with purpose to be any sort of substantial vandalism, and also very easy to remove with iso if you don't want to leave any trace.
Let's give this guy a thumbs up for all the trouble making this video.
Mend it Mark would be proud of you Matt for such a good repair!
Mend it Mark is another great TH-camr! 👍
Not taking away anything TM does, but Mend it Mark has an excellent technical back ground in electronics and engineering.
It that the same person as Mark that works with RMC?
Mend it Mark would have it in perfect working order, before he put it back together. 😛
@17:50 I see the massive rubber gunk on the wheel under the black gear. I think the wheel touches the rubber wheel and was transferred the gunk on to it. It may be contributing to the wobbliness.
I see something.
@17:26 too.
17:28 It almost like there was a rubber belt of some sort.
With the wobbliness, I think it might be the idler tyre, which wasn't in your replacement kit. And it pretty east to change, compared to everything else you've already done. As you know it's the capstan (with it's big heavy flywheel for stability) which gets the tape pressed against it by the pinch roller which actually pulls the tape through as a consistent speed. But that idler tyre is running off the piece you changed and taking up the slack in the tape. I'd say that's where your wobble is coming from.
Couldn't resist: "Every girl crazy for a Sharp stressed man." ZZ Top.
10/10 For your effort Mat.
Hi Matt, another smashing Saturday morning video treat. Instead of using your screwdriver to keep the screw-holes patent while rebuilding them with Sugru would it have been better to use the screws themselves. You could lightly oil them to ensure the Sugru does stick to it and the screws would create their own internal thread as you build-up the pegs.
Was thinking the same thing, I used to occasionally use a 2 part rawl plug putty and would put the screw in when the putty was soft to create a thread then take it out as the putty firmed up a little, then re-attach with whatever I was trying to fix to the wall once the putty was fully hard.
Agreed. I would also have used liquid poly to re-attach the "rattling parts" before doing the Sugru build-up.
FYI: I used Sugru some years ago to "mod" the cover plate for an iron (as in: for ironing clothes!) so that it didn't fall off. Several years on … it's still going strong and showing no signs of wear, going soft, or any other problems. 😉
@@brianthomson6012 . Rawlplastic is no longer available, at least, I couldn't find it online...I believe it used to contain asbestos.
Excellent work from Techmoan i think 👍 I would of given up once i saw one of the screws fall out :D It looked EXCELLENT once all cleaned up to 😎 + it's AMAZING how they make all these things in the past & nowadays(MIND-BOGGLING for my little mind) :D
Cassette deck is date stamped July 31st 1978.
Sounds right. Production run was 1978 to 1979.
Best video of the year 🎉 to my eyes n ears
Praise be to the gods of old technology! Nearly 50 minutes of Techmoan doing repairs!
Nothing I like more than seeing a broken piece of electronics being brought back to life 😊
36:27 I put the pieces back in place with super glue, then wrap them with very fine fiberglass and epoxy. kind of messy but very strong.