HERE SHE IS MY NEW NEW JVC M 70 !

Status
Not open for further replies.

weboguy

Member (SA)
ok so now here are the pics, I've cleaned her inside and outside BUT there seems to be a problem : while it's working 100%, the sound from the radio is louder than hell, but when a tapes plays it's half this loudness, really weaker sound... how come? anyone has a solution? it is playing flawlessly but tape sound is not as loud as it should be, arrggghhh!!!! have to solve this!! other than that cosmetic condition is really awesome oh and music scan is not working also, belt change? I don't know how to do this

View attachment 3908View attachment 3909View attachment 3910View attachment 3911View attachment 3912View attachment 3913View attachment 3914View attachment 3915View attachment 3916View attachment 3917View attachment 3918View attachment 3919View attachment 3920View attachment 3921View attachment 3922View attachment 3923View attachment 3924View attachment 3925View attachment 3926
 

blu_fuz

Well-Known Member
Staff member
That thing is beautiful!!!!!


Sometimes a simple head cleaning and demag will clear up quiet cassette playback.


The music search might not be picking up the pauses in the cassette because the playback is too quiet. Hopefully it is that simple.
 

weboguy

Member (SA)
well I've already demagnetized the heads, should I do it again, do we have to let the bbox on "on" position while demag the heads?
I don't really mind the music scanner, but I want the tape sound to be full and rich as it should!!
anyway she's a beauty!!
 

Lasonic TRC-920

Moderator
WOW, that thing looks brand new! :w00t:

Sweet Score Bro.

Good luck getting that deck volume worked out, I'm sure it's something simple.

Maybe use some Deoxit spray on the function switch, might not be letting the juice through all the way :-D
 

weboguy

Member (SA)
well well well, I've cleaned the contacts again and nothing changes, also the tape speed is a bit faster than it should, not a lot, but a little
now I want to throw it through the window!!! what can i do? it's really annoying these troubles
 

Northerner

Boomus Fidelis
That's a lovely looking M70....congrats!

It only took me a year or so to get mine perfect so patience is a virtue ;) :)
 

weboguy

Member (SA)
I'm not a specialist and I don't know anything about how to change the belt or set the speed, I'm really annoyed now because I want the tape player to work perfect!!!!
 

Northerner

Boomus Fidelis
Belts aren't too difficult on this as far as I remember...get the service manual (its on here somewhere) get the chassis out. Then you can clean the switches properly and do the rebelt. Hey if I can do it anyone can lol :)
 

weboguy

Member (SA)
but I cannot get the chassis out since we must unplug all the switches and stuff, i'll never manage to get them back!!!!! I'm too afraid not to be able to do that, I'm really zero in electronics
 

superlew

Member (SA)
Silly as it sounds, have you tried it with more than one cassette? You can also try cleaning the record swith, but that would require chassis removal for proper access. Cassette motor speed is also an easy adjustment once the chassis is out. With a service manual, organization, and patience I bet you could iron out the kinks. :-)
 

Northerner

Boomus Fidelis
I know what you mean...when I started fixing them up I was pretty scared I'd not be able to put them back together and just ruin them completely. But over time you get more confident and soon you're happy stripping them down. Just need a manual and take pictures of everything as you go.

Or....

Get someone else to do it lol ;) :)
 

Lasonic TRC-920

Moderator
Before you take anything apart, take very detailed pictures and then you can go back in order and look at how you got there.

The service manual is pretty good and this is a very common radio on this site so you'll get the help you need to get her put back together.

OR, does anyone know of a service shop near him in France???

BTW, how does your Line in work???
 

weboguy

Member (SA)
well thanks for your comments
I might try to take everything apart soon, I just need the service manual, wonder if I will understand it though...
anyway, the line in works very well with a phono pre amp, not too loud neither but with a cd player hooked up it sounds terrific!!
so it is possible to set the tape speed correctly? that would be fantastic
strange because the previous one I had (which I sold to new Zeland!!) had a correct tape speed
 

baddboybill

Boomus Fidelis
I'm not a specialist and I don't know anything about how to change the belt or set the speed, I'm really annoyed now because I want the tape player to work perfect!!!!


You don't need to take chassis out to adjust tape speed. There is a plate over flywheel that will adjust speed. As for sound if you cleaned and demagnetized head already you may need to adjust azimuth on head. You will need a very tiny philips head screwdriver non magnetized . While music is playing turn screw holing head in place that has spring on it. Try turning clockwise first slowly and listen for best results of sound. You can also turn counter clockwise but make sure as not to turn out all the way. Good luck and awesome find :-)


Bad Boy Bill
 

weboguy

Member (SA)
thanks badboy but I'm french and I don't understand everything
where is this plate over flywheel? is it inside the boombox or do I get access just opening the tape door? sorry but I know nothing about this
 

Beosystem10

Member (SA)
Don't adjust the tape speed before you change the belts! Yes, as BBB said you can adjust it quite easily but if it wants belts then this could well be how the speed is wrong. Yes, there are other possible reasons but if you try to adjust the pitch and it then becomes too slow with fresh belts fitted, you'll become severely bruised from the kicking you'd want to give yourself.
I'd sort it for you gratis apart from the cost of any parts it needs, just send it over under a carrier pigeon and I'll have it mechanically and electronically perfect within a day or two between other jobs. The soak test may run on for a few years though! ;-)
 

weboguy

Member (SA)
baddboybill said:
You don't need to take chassis out to adjust tape speed. There is a plate over flywheel that will adjust speed. As for sound if you cleaned and demagnetized head already you may need to adjust azimuth on head. You will need a very tiny philips head screwdriver non magnetized . While music is playing turn screw holing head in place that has spring on it. Try turning clockwise first slowly and listen for best results of sound. You can also turn counter clockwise but make sure as not to turn out all the way. Good luck and awesome find :-)


Bad Boy Bill
the best would be to show me pics of what is to do if you could, that would be awesome!!!!
 

blu_fuz

Well-Known Member
Staff member
Beosystem10 said:
Don't adjust the tape speed before you change the belts! Yes, as BBB said you can adjust it quite easily but if it wants belts then this could well be how the speed is wrong. Yes, there are other possible reasons but if you try to adjust the pitch and it then becomes too slow with fresh belts fitted, you'll become severely bruised from the kicking you'd want to give yourself.
I'd sort it for you gratis apart from the cost of any parts it needs, just send it over under a carrier pigeon and I'll have it mechanically and electronically perfect within a day or two between other jobs. The soak test may run on for a few years though! ;-)

If I remember correctly, don't you have to remove the screw and the plate that adjusts the speed in order to get to the belt to replace it?


I would get in there, mark the speed screws location and how many spins it takes to remove, change the belt, and put it back together.


I'm sure the belt is just slipping causing the slow playback.
 
Status
Not open for further replies.