Hi i just bought this Sanyo M9977 Boombox, and it needs a servicing. Everything seems to work except the play button on the tape player doesn't stay down. It will play if you hold it down however. I haven't opened it up yet, was hoping someone could give some possible situations that would cause this problem so i know what to look for before i dive in.
Help with Sanyo M9977 Repair
- Thread starter docnak
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Thanks for the reply. I didn't get responses fast enough so i started taking this thing apart. There seems to be next to nothing as far as repair tips go on this thing, and im having trouble getting to where the belts are. It seems like there is a hidden screw holding the main board down and i cant seem to find it. If anyone knows anything about this please let me know!T-STER said:
Gently - VERY gently (to avoid soldering fractures and other damage) - try applying a slight upward pressure on the board to identify where the resistance may be but ensure you have found as many of the securing screws before attempting this.
Another idea is to draw an outline on a piece of card the same shape as the board with the screw locations drawn on then, as you remove each screw, screw it into the card through the corresponding marks. I'm not familiar with this particular BB but there are cases where some screws may be a different specification.
Good luck.
Another idea is to draw an outline on a piece of card the same shape as the board with the screw locations drawn on then, as you remove each screw, screw it into the card through the corresponding marks. I'm not familiar with this particular BB but there are cases where some screws may be a different specification.
Good luck.
resistance seems to be right in here. i've already got nearly every screw i can see out. Doesn't look like theres any way to attack it from the front. The bottom of the board (where u can see the little half circle) comes pretty far out, but thats it. I've also tried to remove the entire assembly from the case but its not budging. Ive thought that maybe some wires need desoldered but i cant really see any that are hindering it from coming out!MyOhMy said:
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So... I removed all the cassette buttons and now the board feels really loose in there. Now the problem seems to be that i cant squeeze the volume and tone posts underneath the plastic case. Not even sure that this will free it either!
I finally got the unit out, and aside from being a pain it looks like i can replace the belts. However i am not seeing the reason the buttons wont stay down. The Play FF REW and will go down but not stay engaged. Any feedback is appreciated.
Turn the flywheel in one direction and do several turns. If nothing happens rotate in the opposite direction. You should hear a click if there is some sort of reset is done to the deck mechanism.docnak said:
I believe this has to do with deck reset.
In some cases there is a long metal slide bar that moves sideways and lock and release buttons. That liver can get stuck without lubrication. Press FF and study the button locking mechanism.
im not sure what flywheel is. Im not even really sure how.... but i got play to stay down. Now REW and FF still wont stay down. I'll keep poking around i guess. Every time i walk away and come back to it i get a little further!
was just thinking... is there a chance they were designed to be pressed and held to operate?
was just thinking... is there a chance they were designed to be pressed and held to operate?
OK! I got all 3 to go down and stay down! Now my only concern is the record button doesn't seem to do anything. Will this ONLY depress if there is a recordable tape in it?
There is a small lever in the cassette compartment that needs to be pressed for the record and play to depress at the same time. If you have a brand new tape those tabs at the bottom stays there. We break those tabs to protect over recording after recording musis. Check your tape and see if those tabs are broken or not. If it is broken on the cassette tape put a scotch adhesive tape over the hole and cover it. This will keep the lever not going in the hole and prevent over recording.docnak said:
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well the problem is i cant get the record button to go down no matter what kind of tape i have in there, or if there is no tape in there at all. I have gotten everything else to work. I'm contemplating putting it back together and going on without record function.BoomboxLover48 said:
This is a mechanical deck and most likely will need full service restoration. Cleaning of most internal parts including heads,pulleys,old grease, and dirt buildup all around,rubber tires if applicable, possibly new tires, belts and pinch roller. Demagnatizing of tape head. Cleaning record switch. Fresh lithium grease.
Also to get record to go down and lock you could press record release tab located inside tape compartment on bottom right corner
Also to get record to go down and lock you could press record release tab located inside tape compartment on bottom right corner
I have pretty much cleaned everything in the tape deck (which im pretty sure is how i got the buttons to work, thanks T-Ster!). Everything else looks to be in good shape and i was actually impressed with the amount of elasticity the belts still contained! I am an amateur tinkerer and take apart not only boomboxes, but pretty much any vintage audio i can get my hands on. Honestly have never demagnetized anything! What is the purpose?baddboybill said:
Here is what I'm looking at. Where is this record release tab? Also the little black tab near the orange wire seems to be the record mechanism, it only drops down about 1/8 inch before stopping.
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When you push on that tab out releases the record. While doing that since you have deck out you should see on other side what might be hanging up the record
Here is the other side of the deck. It looks like the black tab* would push the metal slide down, but it's not moving.
right side of pic is the top side of deck
right side of pic is the top side of deck
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