Another Arcam alpha 5+ Issue

[filholder]

Hi

I have finished tweaking up my Arcam alpha board. New caps on both boards, new diodea, new op-amps etc. Basiclly loads of stuff as advised. However i now have an issue. The machine when first plugged in work perfectly but after being on for maybe 30 mins passed a mains humm into the amp.
I have unshielded inteconnectcables but have replaced them with shielded one with no joy. I have also built several different mains cables and this hasnt helpped. The current one is a rather sophisticated one, this:-

http://www.tnt-audio.com/clinica/ttse.html


so i am pretty sure it isnt the mains cable. However if when it is humming i hold the mains cable the noise stops, as it also does when i touch the meatl work of the cd player. Does this mean the cd has a bad earth somewhere, I guess it does but before i take the whoel thing apart for the fifth time just wanted to check.

Fil

 

[tubenut]

Check solder joints around the mains connector and fuse. Once had an Arcam where the fuse just came out of the pcb. Apparently arcam used to sub pcb loading and soldering in busy months and the subbies did not do the greatest work.... Especially on bigger components where more heat and solder is required. Assembling and dis assembling may have also cracked a track linked to one of the cvarious connectors. (RCA maiins etc)

Later

 

[filholder]

Cheers Tubenut,

Ill do just that , funny it had been perfect maybe is was changing the mains plug a lot has crack something.

Thanks mate