Hi! I recently grabbed my dad's old Sharp RT-1010 cassette deck, since he wasn't using it.

The play side works nearly flawlessly, however, the recording side will not function whatsoever.

I'm of the opinion that this is due to the record function being stuck down (as this is the only button that cannot be pressed), or something similar having occurred, and therefore the deck needs to be reset in order to allow me to play anything. I opened it up and checked the belts, and they all seem to be fine, and although the remaining buttons function fine, the mechanism does not want to spin. 

Does anyone know anything about this deck, or similar decks, that could lend me a hand in how to repair this issue? I can't figure out how to dismantle it any further than just the top cover without having to pull any ribbon cables out. 

Alternatively, if someone could locate a service manual for this model, that would be appreciated too, as I've had no luck in tracking one down online.

EDIT: After some more thorough testing, I've found the sound of working head to be very muffled sounding. Is there anything I can do about this, short of replacing the head? I've tried using a head cleaning tape. 

Here's a picture of it.

Hi

It is possible that you can't push the record button down because there is no cassette in the deck. If you put a fresh blank cassette in there you should be able to push the record button. On the top edge of a cassette there are some slots, two of witch will be partly covered by a plastic tab. These are the record interlock tabs. These tabs being in place allow you to record on the tape. If you remove the tabs (They just snap off) you can protect the recording. The presence of these tabs is detected by small lever inside the cassette compartment. With no cassette in the machine, or with a cassette without the tabs, you will not be able to press the record button.

The fact that the record deck isn’t working is probably down to the main belt. These belts may look ok but they only have to stretch a little and the machine will stop working. Could also be down to dried out lubricant in the mechanism but I would go for replacing the belt first. The dull sound is most likely a very dirty head. I don’t recommend head cleaning cassettes; they do more damage than good. Use a cotton bud stick with its tip soaked in isoprpanol alcohol. Gently rub the surface of the head, you will see the dirt on the end of the stick.

Hopet his helps.

Well, I cleaned the head a bit with some alcohol, and it does indeed sound better, though not perfect. It seems to sound quite nice with certain tapes and really really muffled with others, though I'm assuming this may be due to the fact that playback deck doesn't support metal tapes. 

I'll look into a new belt for the record deck, it does indeed seem to be the issue, as the head doesn't rise when I hit play unlike the play deck. 

Thanks!

Does anyone know what kind of belt I would need to get to get the recording side up and running? I only know about Walkman belts, so I'm not really sure what size is compatible with this.

Your best bet is to remove the belt and measure it’s width and diameter carefully, if it looks stretched you should go for one that’s a couple of mill less but make sure it is not too tight. There are people on ebay who sell selections of belts and there is a company called Nikko electronics that will sell specific belts (though their shipping costs are a bit steep.) You could also compare the belt with the one on the playback deck, this does mean more of a strip down, but if the belts are easy to remove it will be worth doing this. (Might even be worth replacing both belts anyway, if one has gone the other may not be far behind it!)

Those are excellent ideas! I'll work out how to dismantle it and give that a shot - will post updates here later on if anyone cares!

I care!  Would like to see how you get on.

Well, I got the time to open it up again and have a look today, and did so intending to check the belts. It seems the belts themselves are fine, as when I turn the cogs with my finger, everything seems to function for the most part. The issue seems to be more to do with the motor, as when I switch it on there is no indication that the motor is turning or even attempting to do so. There is no sound and no movement except for the small switch that goes up when I hit "play". 
Is there anything simple that could fix this, or does this sound like a dead motor? 
What do I do?