SONY CFS 590S

[BoomboxLover48]

My Sony 590S was working fine and when I took it out yesterday cassette on play mode is making loud humming noise, but can hear the music play. The VU meter also stopped working. Radio plays well on both channels.

I was wondering what could have caused it!

~Royce

 

[hopey]

Faulty audio cable from the tape head.

 

[potsy61]

I would also give the mode selector switch a good work over

 

[BoomboxLover48]

Faulty audio cable from the tape head.

I will look into it! Sorry I missed this message Hopey!

 

[BoomboxLover48]

I would also give the mode selector switch a good work over

I did that cleaning, but will try again.

 

[BoomboxLover48]

Mode selector switch was cleaned well. Still the cassette section with or without a cassette will make loud noise.
VU meter also stopped working.

I can see the audio cable is tightly tucked using a rubber sleeve in a metal slot.
The paddle wheel that dampen the cassette door spring was also caught on audio wires from the head. I relieved it all but still it makes loud noise.

There is always something to worry about.

I will do a good cleaning to the record switch and see if that helps!

 

[BoomboxLover48]

No improvement and the hum continues with some crackling... I have to leave the cassette section alone...

 

[BoomboxLover48]

After replacing the belts there was no sound from the cassette section. Today I brought it out to test. It sounds not loud on cassette but a hum on either the right speaker or left speaker when I slide to stereo or stereo wide. Cassette plays and records but the hum is there.
VU meters don't work anymore.
Now my Sony V8 and 590S both has issues.
Paid a high price for both from overseas.

 

[Superduper]

Honestly, these symptoms really are consistent with dirty record/playback switches. They aren’t as easy to clean as you may think and spraying them would be like trying to drench a snail when it’s retracted in its shell. The metal shell does a fantastic job of shielding it and if the spray manages to gets past the shell, then you need to contend with the nylon slide which is also hooded and encapsulates the slides. Your best bet is to stand boombox up on end and try to attack from the ends hoping the fluid will seep down and through while working it.

 

[caution]

If you hear a constant hum, I'd be suspicious you have a bad electrolytic.
You might want to test any on the power rails.
I've had more than one situation where these bit the dust and introduced mad buzzing

 

[BoomboxLover48]

Thanks so much!

Thanks a lot!

 

[potsy61]

My CF 590 did the same .. loud hum playing cassette in one channel .. radio fine .. naturally thought broken shielding on the wires to the tape head but all good
The reversing channel switch didnt flip the hum to the other channel so hum originating deeper up the line into amplifier . Anyway on my test bench shortly after the main fuse popped and kept blowing violently.....so I had to replace transformer 18volt Ct was my guess and all is good no hum... only using a ohm meter nothing appeared catastrophically wrong or shorted with the original transformer.. I couldn't be bothered with a megger, just replace the tranny why fight city hall for 20 bucks . I tried to think of a way the issues were connected but remember the radio had no hum so not likely rectifier / caps unless theres a different power source pathway .. I dont have schematic . And F** me the battery voltage / signal meter was faulty as well ( I hadnt paid much attention to notice when it died ) ... maybe the hum over drove the meter ... I had the unit working so well, ready for sale .. ah the world of vintage portables ... I must say FM thru these systems is so listenable

 

[potsy61]

Oh I forgot to say years ago the VU meters had died I replaced them and used the same facia ...I did think after chucking out originals I should have looked under a magnifying at the pivot pins or the coil spring may have been fixable