New Owner of M-X960, Need Advice

[mbonn82]

Hey all,

I am a new member to the forum and a new to boomboxes. I recently picked up a Sanyo M-X960 from an estate sale. The condition of the boombox is absolutely immaculate. I have attached some pics. The good news is that the unit powers on and the radio works. Also, all sound and control knobs seem to be functional. I am by no mean an expert, but I have managed to identify a few issues as well.

The unit powers on when I plug the power cord in, but the power button itself doesn't turn the unit on or off. It feels correct, clicks in and out, but doesn't actually do anything.

The tape deck is completely unresponsive. I have put a tape in, but none of the buttons below the deck seem to do anything.

The Line In/Phono input also doesn't appear to be working. I've plugged a couple working sources but cannot seem to get any output from it.

I am somewhat mechanically inclined, but also by no means and electrical engineer. I just wanted to get some advice from the group based on the issues I'm seeing, should I attempt to repair? Or is it best to sell it as it is? I would like to keep it if I could get it working, but I also don't want to do more damage attempting to repair it and spend a ton of $$$ in the process.

Thanks

 

[Tinman]

Welcome and congrats on a great purchase.

It most likely needs new belts but it could also be a problem with your function switch.
To do it right, you'd need to open it up and clean all the switches and pots with a cleaner such as Deoxit (make sure it's not plugged in).
If you do open it up, take lots of pictures so you know how to get it back together.

 

[Superduper]

That specimen is in excellent condition, it is worth getting it fixed, even if you need to have it professionally serviced.

On most boomboxes, the decks operate independently from the main switched circuits because the deck mechanism has it's own power switch which is activated when the deck is playing. This is so that the deck can operate without requiring the power to be switched on. Your situation is very common when the main drive belt slips or breaks during playback. As the switching action relies on the rotational motion of the capstan flywheel to trip it, and a deck with snapped or slipped belt is unable to rotate that flywheel, ergo the switch is stuck in the ON position, unable to switch off until the flywheel rotates until the deck is reset. Although we are talking about the power switch within the deck, it also affects any function including radio or AUX that relies on the main power switch. In fact, tapes are often used as a sleep timer feature by simply playing a cassette tape and switching the function to the desired mode. In this scenario, the radio or aux or whatever mode was selected will play until the cassette reaches the end of the tape, at which time, the set shuts off.

As for a non-operational AUX mode, cleaning switches of corrosion or oxidation might be the culprit. In particular, the function switch but I would say all switches should be cleaned.

 

[goodman]

to forum. This boombox look fantastic!!! Just need little service.

 

[Lost&Found]

This has to be the one that was for sale near St. Cloud. Was watching the auction too but wasn’t sure I’d be able to drive that far, from Minneapolis, to pick it up. Congrats. Nice to see it again. Reading the auction listing description I assumed it would just need a good cleaning and belts like Superduper is advising. I would definitely listen to his advice. He knows his stuff. Be careful but don’t be scared. Fixing these is one of the most gratifying things I’ve experienced.

If you ever do want to sell it lmk I assume you’re in the area.

 

[Fatdog]

Sanyo boomboxes seem to be notorious for sketchy switches and potentiometers. Give them a good cleaning and go from there. Definitely keep it!!!

 

[mbonn82]

This has to be the one that was for sale near St. Cloud. Was watching the auction too but wasn’t sure I’d be able to drive that far, from Minneapolis, to pick it up. Congrats. Nice to see it again. Reading the auction listing description I assumed it would just need a good cleaning and belts like Superduper is advising. I would definitely listen to his advice. He knows his stuff. Be careful but don’t be scared. Fixing these is one of the most gratifying things I’ve experienced.

If you ever do want to sell it lmk I assume you’re in the area.

You are correct! I'm in the Mpls area too but have family in StC that were able to pick it up for me.

 

[mbonn82]

That specimen is in excellent condition, it is worth getting it fixed, even if you need to have it professionally serviced.

On most boomboxes, the decks operate independently from the main switched circuits because the deck mechanism has it's own power switch which is activated when the deck is playing. This is so that the deck can operate without requiring the power to be switched on. Your situation is very common when the main drive belt slips or breaks during playback. As the switching action relies on the rotational motion of the capstan flywheel to trip it, and a deck with snapped or slipped belt is unable to rotate that flywheel, ergo the switch is stuck in the ON position, unable to switch off until the flywheel rotates until the deck is reset. Although we are talking about the power switch within the deck, it also affects any function including radio or AUX that relies on the main power switch. In fact, tapes are often used as a sleep timer feature by simply playing a cassette tape and switching the function to the desired mode. In this scenario, the radio or aux or whatever mode was selected will play until the cassette reaches the end of the tape, at which time, the set shuts off.

As for a non-operational AUX mode, cleaning switches of corrosion or oxidation might be the culprit. In particular, the function switch but I would say all switches should be cleaned.

Thanks for the great insight. I just ordered a belt kit. I'll keep the group updated with my findings and progress.

 

[mbonn82]

Cracked it open yesterday and found a nice surprise. The original retail tag fell out from inside. Not sure how it got in there, but I think will be a nice icing back on the cake when everything is finished up.



Fortunately the interior appears to be completely untouched from what I can tell. I got all the dust bunnies out and did identify that there's definitely broken belts. So I will attempt to tackle that when I receive them.



As I mentioned previously, I was having issues with the Line In/Phono not working. The issue wasn't with the functionion knob, it was actually the rear Line/Phono switch. I Deoxit'd it and wouldn't you know, works pefectly now. Plugged in my turntable and it sounds great. I also Deoxit'd the volume knob which was a bit staticy when turning, and that is now also resolved.

Is there a way to regain the smoothness of the knob though? I'm sure the Deoxit probably removes any grease that appears to be on all the knobs. Am I able to reapply that somehow? If so, is there a particular spot it should go?

As for futher disassembly, I did reference the service manual, but it wasnt' super clear on the order of operations for taking this all apart or how far I need to go to replace the belts. It appears that there's an interior frame, do I just undo the screws holding that frame in and the whole internal should come out?

Thanks in advance all for the assistance!

 

[floyd]

Looks like you have to remove the inner frame to access the deck . the tape counter belt is driven by the drive spindle so that would be impossible to replace without access to the front of the tape deck.

 

[floyd]

Cracked it open yesterday and found a nice surprise. The original retail tag fell out from inside. Not sure how it got in there, but I think will be a nice icing back on the cake when everything is finished up.

View attachment 59361View attachment 59362

Fortunately the interior appears to be completely untouched from what I can tell. I got all the dust bunnies out and did identify that there's definitely broken belts. So I will attempt to tackle that when I receive them.

View attachment 59363

As I mentioned previously, I was having issues with the Line In/Phono not working. The issue wasn't with the functionion knob, it was actually the rear Line/Phono switch. I Deoxit'd it and wouldn't you know, works pefectly now. Plugged in my turntable and it sounds great. I also Deoxit'd the volume knob which was a bit staticy when turning, and that is now also resolved.

Is there a way to regain the smoothness of the knob though? I'm sure the Deoxit probably removes any grease that appears to be on all the knobs. Am I able to reapply that somehow? If so, is there a particular spot it should go?

As for futher disassembly, I did reference the service manual, but it wasnt' super clear on the order of operations for taking this all apart or how far I need to go to replace the belts. It appears that there's an interior frame, do I just undo the screws holding that frame in and the whole internal should come out?

Thanks in advance all for the assistance!

That retail tag is amazing and has a lot of information about the box.
Also thank you for that inside pic of the big Ben . I've seen these in person but never really saw a clear pic of the inside.

 

[BoomboxLover48]

Play or any transport buttons on the tape section was not working on mine and later found out it was a broken tiny micro contact switch. Micro switch failure is very common with the BigBen.
In my case, it was the main transport contact switch. Our Bill (baddboybill)was kind enough to hand over one free to me when he was in IL.
I was unable to locate that link for fixing my BigBen.

 

[mbonn82]

Play or any transport buttons on the tape section was not working on mine and later found out it was a broken tiny micro contact switch. Micro switch failure is very common with the BigBen.
In my case, it was the main transport contact switch. Our Bill (baddboybill)was kind enough to hand over one free to me when he was in IL.
I was unable to locate that link for fixing my BigBen.

Thanks, I'll confirm once I get the mechanism pulled out, but from what I can see from the outside, they appear to be intact. I'm just noticing that the flat belt is nowhere to be found. More to come.

 

[mbonn82]

Play or any transport buttons on the tape section was not working on mine and later found out it was a broken tiny micro contact switch. Micro switch failure is very common with the BigBen.
In my case, it was the main transport contact switch. Our Bill (baddboybill)was kind enough to hand over one free to me when he was in IL.
I was unable to locate that link for fixing my BigBen.

Successfully got the mechanism out without breaking anything.



I was able to locate five micro switches, all appear to be intact and not broken. Would you agree?

 

[BoomboxLover48]

Successfully got the mechanism out without breaking anything.

View attachment 59366

I was able to locate five micro switches, all appear to be intact and not broken. Would you agree?

View attachment 59367

View attachment 59368
View attachment 59369
View attachment 59371
View attachment 59372

It looks very clean without any visual damage. I would clean the contacts very carefully with a thick paper soaked with contact cleaner. Stay away from using any abrasive material. Normally silver or silver-cadmium alloy is used as a very thin layer at most contact points in micro switches. Gold contacts exhibit the best corrosion resistance but are limited in current-carrying capacity and may “cold weld” if brought together with high mechanical force.

Gently wipe the contacts with a narrow and thin paper soaked with Deoxit Fader Lube 5.

If you don't have the schematics, please get it from analogalley.

AnalogAlley Service Manuals

www.analogalley.com

The main trigger switch for the play mechanism is shown below:

 

[mbonn82]

It looks very clean without any visual damage. I would clean the contacts very carefully with a thick paper soaked with contact cleaner. Stay away from using any abrasive material. Normally silver or silver-cadmium alloy is used as a very thin layer at most contact points in micro switches. Gold contacts exhibit the best corrosion resistance but are limited in current-carrying capacity and may “cold weld” if brought together with high mechanical force.

Gently wipe the contacts with a narrow and thin paper soaked with Deoxit Fader Lube 5.

If you don't have the schematics, please get it from analogalley.

AnalogAlley Service Manuals

www.analogalley.com

The main trigger switch for the play mechanism is shown below:

Thanks for the tips. I will do that when I replace the belts.

 

[Tinman]

Damn it, I've never had one of these.
I was hoping you'd give up and sell it to me
Good job so far.

 

[mbonn82]

Not sure if this is a problem or not, but I noticed there is quite a bit of play in the motor mount. I'm guessing these rubber isolators don't quite have the spring they used to in order to secure the motor. The screws are fully seated, but the motor still wobbles. Does anyone have a suggestion for replacement or should i just put a few small washers under the screw heads to fill in the gap?

 

[floyd]

Not sure if this is a problem or not, but I noticed there is quite a bit of play in the motor mount. I'm guessing these rubber isolators don't quite have the spring they used to in order to secure the motor. The screws are fully seated, but the motor still wobbles. Does anyone have a suggestion for replacement or should i just put a few small washers under the screw heads to fill in the gap?

View attachment 59375

These bushings don't look right. Normally the bushings would isolate the motor from both sides.
Basically it should have a rubber piece that is centered in the motor mounting hole but has rubber on both sides . you might just need some shorter screws to mount the motor. Get rid of the bushings all together.

 

[Superduper]

In my experience, some motors ARE mounted on rubber isolators. However, those bushings appear to be hand carved from something, maybe an eraser. I suspect they aren't the correct thickness, maybe you can shim them out with some washers. Yes, a bit of wobble is OK if you are using your fingers to exert force.