Sharp GF7-R radio works, but tapedeck is dead

Hi All,
I have an old Sharp GF-R boombox. The radio works great, but the tape deck seems dead. No movement on play, FF, RW at all. I don't hear the motor running with I push any of those buttons with or with out a tape in it.

Anyone have ideas, tutorials, videos that might be worth while? Or a direction to begin the process of repair?

I'm an amateur. I have soldered before, but it's been a while. If I break it more, it's not a big deal, but you all know how it is... I would love to bring it back to life! I'm just not sure where to begin.

I'm not afraid to take things apart and poke around. Just not sure what I'd need to do.

I'm open to suggestions.
Here is a link to a video I made showing what's up...

 

Might be as simple as disintegrated belts. At this stage they are going to have to be replaced anyway. Motor may be so quiet it can't be heard, even though it could be turning. What is the exact model from the back of the machine? Sharp GF-A1A(R)? Google is showing some variations but the only one that looks the same is A1A.

Google up the belts and check out what is available. Then do careful searching of your models to see if videos of someone else doing the belt changing is out there. Study all available videos. Google and find discussions of your same model in the various boombox forums. So before you even open it up you know what to expect and what to do. (That's what I do before even thinking about buying a model. I want lots of discussion on forums of that model and youtube videos and complete tear down plus service manual .pdf available, belts available etc, .)

 

The actual model number is GF-7R. So far, I can't seem to find any videos or wire diagrams to work from. I did another test, it it feels like the motor is not getting any power. I don't hear or feel any movement with any of the buttons. Attaching a picture of the back.

 

At least the belts come up and are available from some decent sellers like webspareparts who source the EU made ones. They also have an e-bay store. While on e-bay I note there is a Sharp GF-7 Service Manual for $10. Which at least shows exploded parts diagrams and how to take the machine apart. Always very good to have the Service Manual to know where things go in case you get lost and don't know what goes where. (Though one should really take dozens of pictures or, better yet, a high res video as you take it apart. For your own reference and help later.)

I also went through that Cassette2go guys youtube video page, he has worked on a great many Sharp units, but not many of the "mini" ones. Still, Cassette2go, who is around here posting sometimes, may have some more answers.

If the motor is not turning I would suspect perhaps a mechanical leaf switch contact not working, needs cleaning, lots of connections to clean etc., Probably just something basic. But who knows. At some point you will just have to bite the bullet and unscrew the back of the machine and see if it can be exposed and see what's going on. Take pictures and post them here. There are a lot of great and experienced people here who can guide you along. But you need Patience and Perseverance. The process could takes weeks of back and forward step-by-step work. And I am not the expert by any means. I won't be able to help much.

 

Wow! Mr.X that looks to be right service manual I think... a nice 11.4mb .pdf file at archive.org! Looking through the manual (I see various models) and that just taking the case apart is a "big project" The original poster should carefully review and study that manual, print out the relevant pages and... think what to do next.

 

Hi Everyone, I was able to get it open and remove the casset player section. I plugged it in, and I can see that when I switch from radio to tape casset, the motor turns about 1/4 but then when I push play, fastforward, or rewind, no motor movement at all. Anyone have ideas? Here is a video:

 

And here are some pictures.

 

Progress!! I think... I found what I think is a leaf switch, but not sure. Check out this video. When I push this part, the motor spins! I need to get some Deoxit, and see if cleaning it fixes the problem. I don't get how this switch normally moves. Check out the video

 

More insight! This is a better lit video of what's going on. I realized that that switch I'm touching sends power to the moter regardless if a tape fastforward, rewind, or play button is pressed. So, somplace else, needs to be cleaned or checked out. But I don't know where!

 

hi, from the diagram I managed to extract this part of the circuit...I would check if there is oxide on the terminal contacts

 

Ok, so I have sprayed and cleaned a bunch of areas... then I put it back together. That was really hard, and the counter and lights in the front are not lined up right, so I'll need to do it again.
BUT... Some progress. See this picture of the top? Where it says "tape" "radio" "line in" So, the way it's suppose to work, is that when it's on radio, the tape deck stops, when it's on tape, the tape player works.

So, now, if I put the switch between radio and tape, the tape deck gets power, but I can still hear the radio. If I pus the switch all the way to radio, the tape player stops moving. So, I'm wondering if the problem is with this switch?

 

Ok people. Could the problem possibly be this capacitor? When the switch is half way between radio and tape the tape has power. When it’s all the way to tape it does not.

also can anyone helped me figure out what that capacitor is so I can order a replacement?

 

Do people think this is what I should search for to replace the capacitor? Nichicon USW1A330MDD Audio Capacitor 33uF 10V 4x7mm RM1.5 85°C
If anyone finds a link to the correct one on Amazon or someplace, please post it here.
check the pictures...

 

Ok a big clue! I found this picture of the “main switch”. This is the switch in my video, that when I push it with a tool, the power goes to the deck.
In the picture, there is a silver or gold curved part near the top.
In mine, that part was loose in the box. But I also found a piece of broken plastic that looks like the picture.
On mine, I can see the switch but can’t access it because one screw is stripped.
But this is what I’m zoning in on!

 

Another clue here: https://boomboxery.com/forum/threads/sharp-gf-7.26223/

 

Check this out.. Leaf Switches on RipOffBay.. These are cheap.. https://www.ebay.co.uk/itm/18577720...lt7knw73OmLZvjynEEDxXQSYr4|tkp:Bk9SR97N06jKYw

 

This is great! Thank you so much for the insight. I ordered a new one (or a bunch... lol...).
There is one screw that is stripped, it coveres the wheels that the bands go around, so I can't gain access to the switch.

I also ordered a special pair of pliers meant for small screws that are stripped. Then I'll need to replace that screw I think.

If I can get that screw out, I can see about glueing the switch back together. Or, just wait for the new one to come, which will be like 3 weeks away unfortnatly.

Oh well. I also ordered the band replacements. I don't know if they are needed or not, seeing how I have not yet heard the deck play, but I figure, while I'm in there, it can't hurt to put new bands on.

I will keep people posted!