Sanyo M7880L mini not booming!

Just got a lovely Sanyo M7880L, it's blue and pretty minty! Everything works but one channel is really quiet Same on tape, radio and line in.

I've cleaned all the switches and even the headphone socket but no joy. Can't work out how to get to the record bar to clean that so I did the press record then stop 20+ times but no improvement. Not worked on a mini before, it's a bit fiddly!!

Tried headphones in the headphone socket and its great on both channels

Gonna try a spare speaker tomorrow to see if the speaker is faulty but anyone got any suggestions after that?

Could be a faulty A/F amp as the headphone socket may be supplied from somewhere upstream of the output devices since 'phones don't need anywhere near as large an output in most cases, so are usually fed from the A/F preamp. The easiest way to check for a faulty speaker would surely be to swap the connections from one to the other and see whether the same channel is dead when you've done that.
As is the case with your Sharp, I'd gladly check this out for you if you should find yourself up this way.

Beosystem10 said:

Could be a faulty A/F amp as the headphone socket may be supplied from somewhere upstream of the output devices since 'phones don't need anywhere near as large an output in most cases, so are usually fed from the A/F preamp. The easiest way to check for a faulty speaker would surely be to swap the connections from one to the other and see whether the same channel is dead when you've done that.
As is the case with your Sharp, I'd gladly check this out for you if you should find yourself up this way.

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yeah what he said.

Cheers John I'll try speakers tomorrow when I'm not half asleep. Only got 3 minis so keen to get this one going, it's a really quality box and sooo skinny.

I can see me calling round yours with a selection of troublesome boxes ha ha, there's only this and the GF9000 giving me problems, all my others are fully functioning

ledmeter said:

Beosystem10 said:

Could be a faulty A/F amp as the headphone socket may be supplied from somewhere upstream of the output devices since 'phones don't need anywhere near as large an output in most cases, so are usually fed from the A/F preamp. The easiest way to check for a faulty speaker would surely be to swap the connections from one to the other and see whether the same channel is dead when you've done that.
As is the case with your Sharp, I'd gladly check this out for you if you should find yourself up this way.

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yeah what he said.

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Thanks Warren

Things we should NEVER post to public web fora number 317b:

Northerner said:

.......all my others are fully functioning

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I think "they" call that the law of diminishing functionality.

Actually, thinking about it, its probably fairer to describe them as mostly functioning or sufficiently functioning

OK so last night I had another go at this and managed to get to the record bar to clean it...no joy

So I tested the speaker on the dodgy channel and it works fine so its an electronic fault beyond my meagre skills. So as a temporary fix I've desoldered the duff channel and jumpered the two speakers together...so now its a two speaker mono box As its such a tiny box with the speakers close together I doubt I'd notice the difference but if I take a trip to see John/Beosystem10 I'd take it with me to get sorted properly.

Best bit about joining the 2 speakers together is that the LEDs work on volume so you can slide the silent channel to full to maximise the LED bounce whilst controlling the actual volume with the other slider

Will finish the cleaning tonight then post the pics of this beauty

The 7880 is a nice box hope you get it sorted, never seen a blue one, I have a red and black, you need to post some pictures working or not

mrp32 said:

The 7880 is a nice box hope you get it sorted, never seen a blue one, I have a red and black, you need to post some pictures working or not

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Yeh the blue is gorgeous, kinda metallic almost, will post it later, need to get maximum gleem on it first

Northerner said:

The 7880 is a nice box hope you get it sorted, never seen a blue one, I have a red and black, you need to post some pictures working or not

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Yeh the blue is gorgeous, kinda metallic almost, will post it later, need to get maximum gleem on it first

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Iv got 1 in bits at the moment. Any chance you have a photo of how the belt goes on? Or how do you get deck out easily.
Cheers

I do take photos of fixes but this one is too long ago! The deck doesn’t come out. I seem to remember it being a bit fiddly and involving small gaps to get to the belts. I don’t have this one any more so can’t check

Sanyo minis have notoriously confusing model numbers but I’m certain the skinny blue one would be an M7780. The M7880 is a larger higher end mini.

This is as far as got out, at this stage. Can probably get further, just have to squeeze all the wires around the frame.


This is as far as got out, at this stage. Can probably get further, just have to squeeze all the wires around the frame


Whoops. Twice

It looks like it takes one square belt that goes around both the flywheel and the white pulley ,then a flat belt from the flywheel to the motor spindle.

Oh. I actually found a belt when I took it apart. Nice that it was just broken, so I found another pretty much same size.
I figured it should be around all 3 wheels, but to do so it's got to be behind the little board and to be threaded over a pair of black wires going into the deck (where screwdriver is) Which means I have to get all wires/plugs out and get on the right side of the black wires. I think. Ha

It looks to me like you can remove that small board or take the screws out and lift it up enough to slip the belt under it.

You will have to remove that leaf switch out of the way too but that's pretty easy.