Audio crackling - please help!

[builtclever]

Hi all,
Can anyone help me to repair the fault that is causing the crackling sound on audio please? I have layman skills, but could possibly tackle this if given instructions.
It was my Dad's unit, so very sentimental and I'd like to keep it going.

Thanks in advance.

Clive.

 

[Hajidub]

What's the unit? Most likely needs a deoxit treatment from the interior on the selector and volume pots. Spray and work them vigorously.

 

[builtclever]

What's the unit? Most likely needs a deoxit treatment from the interior on the selector and volume pots. Spray and work them vigorously.

GF767. I sprayed all pots and switches. It's not affected or caused by knobs or slider movement, merely when the volume is turned up, whether on radio tape or input.

What's the unit? Most likely needs a deoxit treatment from the interior on the selector and volume pots. Spray and work them vigorously.

 

[Hajidub]

There's a long plastic slider on the main board. This is a record switch that can gum up and affect playback. Spray the crap out of it and work by hand or record button. Any further and you're into recapping and replacing transistors.

 

[XLVII]

Hi. If I am reading post correctly, crackling occurs at higher volume levels and not when moving controls. Older radios(20 +yrs.) often need electrolytic capacitor replacement. Your output filter caps, final stage before speakers may be leaking and be far below limit leading to "clipping" when overdriven, which happens as more power is fed into system.