superstar 360 making strange noise

[yogibear2781uk]

superstar 360 fm

my superstar 360 has not been used for about a year ....
and i got it out the cupboard and set it up ......
turned it on and its making a strange noise (like its being some one is keying up and de keying very quickly )
it transmits perfect on all bands......

any one got any ideas as what to check please......

[cb4ever104]

Does it happen on all modes ?

[yogibear2781uk]

yes all modes the same

[cb4ever104]

Does reducing the RF gain reduce the noise ?

[yogibear2781uk]

still the same and ive disconnected the antenna and still the same

[cb4ever104]

Sorry . Does the S meter move up and down in line with the noises ? Maybe posting a video might help .

S.

[cb4ever104]

Also . Tighten all the screws that hold main pcb to the chassis .

[yogibear2781uk]

have tightened all the screws and no the signal meter is not moving
ill try video it a bit later

[cb4ever104]

OK . Does it actually receive incoming signals on the selected band/frequency ?

S.

[yogibear2781uk]

yes got good signals

[cb4ever104]

Final question from me . Does the noise increase or decrease when the volume is adjusted ?

[13EL121]

Maybe a blown electrolytic capacitor?

[yogibear2781uk]

no it stays the same

[13EL121]

Maybe a photo of the inside would help. A blown cap in the audio section could cause this.

[cb4ever104]

Looking at all the symptoms , it definitely looks like a fault around the audio amp . As Ralf says it may be a bad cap . Or it may be the audio amp itself . A scope would be your best friend just now . If you don't have one then check the voltages on the audio amp anyway . I presume it's mkII 360FM ? If so , then here's what you should have .

IC8.JPG