I posted about this in AudioKarma but after being invited here I will also post my experience working on this unit. I’ve had this for a few years with hardly any issues. Got it for $25 at goodwill. It had normal old unit issues like crunchy volume and tone controls and sometimes slow reaction to FF and RW. I mostly use this to transfer tapes from the deck to my computer. But recently I accidentally hit record for a split second and then stop and play. After this I got a loud and low hum on the left speaker / channel. This did also appear when sending audio out to the computer. Based on some advice and research I ended up taking the entire thing apart. I eventually got the tape deck out attempting to keep good track of all the screws and wires I undid. I saw that the belts were unsurprisingly saggy and weak. I ordered some new ones and proceeded on to my original quest. The motor bushings were super flattened and shrunken which means the motor wobbles around in the housing. I later deduced that this is probably causing the occasionally persistent warbling sound. Bookmarked that for a future fix. In the meantime I jammed some cardboard between the motor and the housing for some stabilization. I couldn’t get to the backside of the circuit boards without major surgery so I just cleaned anything that looked a little dirty and shot some deoxit into all the switches and knobs. The recording switch doesn’t have any holes but I just shot deoxit into the edges. cleaned the tape heads, roller and capstan. Put the whole thing back together (no extra screws!) and viola! The hum was gone. this is when I noticed the warbling sound and also ordered belts. The other new and unaddressed issue is that AM radio no longer works at all. There’s no static or noise. Just zero. I must’ve screwed something up while poking around. I can’t seem to find the issue. Another user suggested cleaning the AM diode etc as I might’ve (and likely did) gotten deoxit in there. I cleaned everything near the radio components again and looked for any obvious disconnects. I also tried to get some deoxit in the AM/FM switch but that has very little access. No progress has been made on that. AM still no longer works. I should also add that the AM/FM knob was so severely stuck on it was the hardest part to get off. I wonder if I broke something getting that off. I tried to lube up that knob second time around but it was still severely stuck. I’m going to shave down the knob plastic or just order a replacement knob. That’s the journey for now. I’ll add a bunch of photos from the internals which were surprisingly clean when i figure out how to on this forum from my phone.
Hello, please make a note of my forum name and then watch this video, allow me to add check out this youtube channel name, this is not the only video of that model in that channel and I no longer have this model. Sorry all I have is a video and the pictures in the video nowhere else.
Wow, those look great in that thumbnail. I have a small thing for mid-sized well-built boomboxes. I'm wondering about the motor bushings, you shoved cardboard inside of the motor? The motors are so small I don't remember opening one up before. Clean the Radio/Timer switch with DeOxit, the switches that change the source are always a source of issues. I'm not sure if this deck does it but sometimes a loose counter belt can also cause issues. They always look good but they get hard, slip a little and cause issues with start/stop because they are tied into the automatic stop. I don't know if there's a lube you can use for getting knobs off (and I'm not talking about EasyGlide). I have small screwdrivers and automotive plastic panel removal tools that help but it's never easy on some of them. We have a thread on here somewhere with computers, show us your setup! I grew up, first, with a Timex Sinclair, then moved up to an Apple II+. I used a tape drive in the beginning and then did some cool stuff on the Apple with one. I've got a small sample of later microcassette, dock, mini-computers (calculator).
I just took a look at your picture of your deck and realized and remembered that hey, that motor does not have a speed control on the motor or separately. Therefore, you cannot change the speed of your motor because it is set from the factory and once it's internal weights controls go bad. Then you have to simply replace the motor with another one from Sanyo and those are very hard to find. I know because I found two of them a while back to replace in a couple units. I have that use the same kind of motor basically In this one The model number escapes m99 m990 there's three nines m9990 not there. We go great me at the moment but I remember it someday and there's a couple more that use the same motor yeah there is a m9999 4. Only three nines and a four k and then we have a m9999 4 with no k.
old Sanyo boombox owner's this is a Must watch video! The GOVERNATOR - How vintage DC tape recorder motors work! https://www.youtube.com/watch?v=yUT512DW8pg All
Little update. I got the new belts in the mail this morning from China. About $8.50 compared to the US seller that was selling for $34. Since I had already taken this apart troubleshooting the low hum it was easy to get the deck mechanism out. Getting the old belts off and new belts in was pretty simple. No major issues. While in there I did put some little foam insulation between the motor and the deck to make up for the shrinking of the bushings. everything is working much better. No major warble sound anymore that I noticed. Kind of hard to tell since some of my tapes are so beaten up. But the tapes I know are in better shape sound great. It’s amazing to have rewind and FF without coaxing the motor into working. And fast! When I rewind there doesn’t seem to be auto stop however. I could have sworn it would before. hmmmm. That is it for now! Thanks for the help everyone.
I believe it's Auto stop only in play mode not in rewind or fast forward as it's not a full auto stop machine mechanism. You see that little plastic tang between the erase head and the playhead when the tape is taut then it will move backwards and shut off the motor. But it won't do that in fast forward rewind that I know of.
Oh no. A few weeks later and the hum / massive noise, worse from before is back when playing tapes. Crap! If I do the record, rewind trick it stops. so I’m guessing once again it’s something in the record switch.
This is a Sanyo It is not your Samuel, but I am pointing to the recording bar switch that you need to locate in your model which is behind the cassette deck and then you need to liberally spray deoxit from one end to the other. While moving that switch it doesn't move very far but you just spray in one end and then work the hell out of it and then spray a little bit more and work the hell out of it and rinse and repeat and spray a little more and work the switch. And after you get it to where you think it's got the stuff dripping out from what end out the other and it snaps back crisply then it should be clean then go and plug it all together and play it. Don't put it together. Just play with headphones if you can. If you don't have any then just play hook up the speakers but don't need to put it all back together because if it's not we're still making noise. Then you need to find the wires that screw to the cassette deck that are as a ground. There should be one or two at least and you need to remove those and then sand the connection and then the platform or the metal that the little metal loop goes to sand both sides and then screw it back together for both and ends and ensure all your grounds are good. While you're in here, you might as well spray the oxid through all your volume controls and switches and anything that has electricity going through it, including your beat cut, switch and just about anything you can think of that you can see that you operate with your hands to make this box give you sound and then like I said before plug enough of it together to where you don't have to put it all together so you can play it and hear it with your cassette. And hopefully by that time you'll have fixed it. If not, go back and do it all again until it gets gone. No noise okay. Sorry I'm not there. I couldn't show you in person but I've done this many many many many many, many, many, many many times
Thank you for the detailed reply. I did all of these things last time I took it all apart but I wasn’t as thorough with the deoxit in the record switch as you suggest so I will do that. I also will clean up the grounds more thoroughly. I’ll probably get to it this week and let y’all know how it turns out. Going to change the belts in my Dual 506-1 first as they just arrived!
