neutralzz 0 Report post Posted January 2, 2006 I've posted in headwize for help look here for my posts: http://headwize.com/ubb/showpost.php?fnum=...=47187&fpage=20 and this: http://headwize.com/ubb/showpost.php?fnum=...=47193&fpage=20 I've recorded down the hum, and analyzed the spectrum. turns out to be 50Hz, which means from the mains, am I correct to say so? grounding, I use the big copper line at the bottom wat do you guys reckon causing the hum?I've tried to shield away the signal lines as you've seen with all those small wires twisted around the signal wires then ground one side of it. only the lead wires to the tube that is not shielded probably power related. i had an old japanese airtight tube amp, transformer faulty after a few years, similar 50hz hum.. Share this post Link to post Share on other sites
squalle 0 Report post Posted January 2, 2006 trafo's fault? but I've tried grounding the input to the op-amp (L channel only). then turn it on. no hum on L channel, R channel has the hum. so I dont think it's trafo's problem. if it is, it should be there no matter wat, am I right? Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 2, 2006 Okay back really less den $100... Couldnt find the 15 -15v transformer... minus the jacks Total parts damage from Koba is $52 after some heavy discount. Might be less if not for the fake alps. $15 Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 2, 2006 After looking at your setup, how come got 3 heatsink. Den my rectifier is round one. den you have 4 trim pots... Share this post Link to post Share on other sites
squalle 0 Report post Posted January 2, 2006 k hum prob found!!! yay!! Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 2, 2006 darn i bought the wrong socket... so what the prob Share this post Link to post Share on other sites
squalle 0 Report post Posted January 2, 2006 haha coz I dun wanna buy the fixed 12v and -12v regulators those 2 extra heatsinks are not really req, but being kiasi, so just put there but I think can do without. totally no heat out of it but the heater sink is a MUST trafo I bought the 2 koba has extra 2 trim pots due to using adjustable regulators I found out the stupid hum just due to the damn contact of the screw on connector sheesh I accidentally pulled the cables from trafo and the board then hum went away hahahaha so silly Share this post Link to post Share on other sites
neutralzz 0 Report post Posted January 2, 2006 lol congrats.. you managed to catch the hum Share this post Link to post Share on other sites
squalle 0 Report post Posted January 2, 2006 wat socket? maybe I can help Share this post Link to post Share on other sites
squalle 0 Report post Posted January 2, 2006 I'm getting a grip of this tube thingy after numerous amount of hours spent staring at this damn thing now enjoy first, before I fix another prob Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 2, 2006 Can spare me the trafo :~~~ Got any spare socket as well? Share this post Link to post Share on other sites
squalle 0 Report post Posted January 2, 2006 trafo has its owner already (not me) I'm building 2 SOHAs wat kinda socket? You still havent told me wat socket Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 2, 2006 (edited) The tube socket... I realise i got the 7 pin one which type of stripboard u using also Edited January 2, 2006 by Kippei Share this post Link to post Share on other sites
squalle 0 Report post Posted January 2, 2006 kippei: check Pm Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 2, 2006 Hmmm I think i halt the building, until I have done the nesscessary preparation... I was thinking of casing it in a acrylic casing Share this post Link to post Share on other sites