Demon 500 not keying up.

[Jimbo165]

I have a friend that brought over his demon 500 the relay just makes a buzzing sound when being keyed up. You put 12v to relay and it works like it should and amp puts out power. I have checked the transistor and doides on keying block they were okay . Know problem is not enough voltage getting to relay but donot know what to do now. Here is a picture of it. Any help greatly needed. Thanks jimbo165

 

[fixer]

I would replace the small electrolytic caps in the keying circuit, plus the 250 uF's in the 12 VDC power supply. I would replace the 250's with 470's like the later models used.

Fixer