gf 9191 humming from tape heads

i have a gf 9191 thats humming from the tape heads, when i hold down the edit button it stops, can anyone shed any light on this prob for me , thanks

I have the same problem on my 9191X-toothpick for now!
I think it's the head adjustment or dirty record funtion buttons or something else?!
Let me know if you fix yours.
Have a good one-GB.

The head cables either are shorted or have a broken ground (shield wire). Check it.

thanks SD will look at it tomorrow

Superduper said:

The head cables either are shorted or have a broken ground (shield wire). Check it.

Click to expand...

Thanks Norm, I also have a 9191 doing the same thing. It worked fine two years ago when I got it, I'll have to check it out eventually.

well after alot of head scratching trying to sort what i thought could be a ground prob, no joy, then i thought id try the record playback switch and bingo prob sorted,

alls well that ends well,

now for the next one

most of my boxes havent be played for prob 2 years

they was all working and now i have about 10 wilth probs

geoffhartwell said:

well after alot of head scratching trying to sort what i thought could be a ground prob, no joy, then i thought id try the record playback switch and bingo prob sorted,

alls well that ends well,

now for the next one

most of my boxes havent be played for prob 2 years

they was all working and now i have about 10 wilth probs

Click to expand...

what was the problem exactly???

i did not understand , im sorry.

and i would like to know in case i get the same.

really.



thank you, geoff.


regards,

john

was a odd humming from tape deck heads John

geoffhartwell said:

was a odd humming from tape deck heads John

Click to expand...

i had that, but i meant, how did you solve it.

thanks

I think he said he cleaned the record/playback bar (switch).

In almost all cases, the very first step in troubleshooting performace issues is a good thorough cleaning and verify. That simple step probably solves 1/2 or more of the problems.

Must be a problem at nearly all 9191.
Mine do the same...
Will also try this cleaning.

Headcleaning was worthless.
Sometimes it hums on the left side, sometimes on the right...

Also suddenly the JVC 550 is doing the same.
Both were working a few weeks ago.... :'-(

It's a design issue. The heads are very sensitive to interference and must be grounded via a cable shield. In many boombox designs, the ground cable goes directly to ground. On others (like the Superscopes and some Sony's have this problem, very very common) the shield wire is not grounded immediately, rather goes through the Play-Record switch. If the play-record switch develops oxidation, a bad connection develops which is the same as an ungrounded play-record head. When left ungrounded, the cables pick up stray EMI or RFI and is amplified by the circuitry causing the hum.

yes, simply spayed some contact cleaner in it its fine now