80's Sanyo MS340k service

[astormsau]

Hi everyone

In another thread I mentioned I inherited some old portable gear a few months back. I've been working on restoring a lovely red Sharp twin cassette unit from about 1985 and now that project has come to its end it's been time to work on another unit.

 

This is a mid 80's Sanyo Mini Boombox. It's basically a Walkman auto reverse tape transport with radio and speakers. The whole unit is DC with an external power adaptor which is how they got them so small. This picture demonstrates it's size relative to my hand.

 

It's a little discoloured from sitting on a window sill for much of its life, originally it was white. Anyhow the issue with this one was the tape mechanism was totally seized to the point you cannot even open the door let alone work any of the controls. I assume the sun has cooked all the grease.

 

 

Here is the little motor with not a belt to be seen.

 

 

I purchased a cheap pack of 30 belts off eBay and set to the mechanism with circuit board cleaner and cotton buds to break down all the crud stopping everything from moving. There were also some pieces which I bent when trying to take the mech away from the front door which I had to get back into place.

 

 

It took about 12 hours work to get the deck back into working order. Slowly cleaning away all the mess and then freeing all the mechanics. Lucky the springs are all mostly in tact and due to perhaps it mainly being used for radio the heads are in good condition.

 

I got fresh grease into the mechanism and new belts fitted. Each issue resolved seemed to reveal a new one to be resolved. There were so many sliding cogs which would not move and buttons which someone had pushed a little too hard and bent a lever and so forth.

 

Originally the auto reverse would not work until I found a stretcher spring which had to be replaced. Once that was done the deck was happily changing sides without issue - I've always loved auto reverse decks. The transport is incredibly small to work on and not easy to disassemble.

 

 

There is one last remaining issue and that is the auto reverse does not work at the end of a tape side - it just shuts off- I've decided that I can live with that for the time being.

 

Here is a comparison shot next to a normal size boombox from the era.

 

 

These little units are quite rare and quite a marvel for their time. I'm enjoying listening to some old tapes on it and being able to carry it around on battery power using some high power rechargeables it lasts for a long time between charges. The radio sounds quite nice with a bit of a 'spacial stereo' sound.

 

 

 

Hope you enjoyed.

 

Drew

 

 

Sent from my iPhone using Tapatalk

 

 

 

[tapeGuy25]

Hello,

 

I have an identical boombox, except it is yellow. Glad to hear you got yours working.

 

How were you able to disassemble the thing and get to the tape mechanism? I can't figure out how. I removed the back half of the case, but couldn't get any further than that. There was a big circuit board in the way, and removing its screws didn't help.

 

I also have the exact same question as you since the belt inside mine turned into goop.

 

I know it has been a few years since you posted this, but I am unable to find any information on this boombox anywhere, except here.

Thank you in advance.

[tapeGuy25]

Hello astormsau,

 

Just wondering if you received the previous message I sent. Hopefully you can help me with my Sanyo MS-340K. Please let me know.

 

Thank you!