50Hz hum from S.E.X. amp, only headphones and left channel.

[mwgrient]

Hey Paul, the hum is still there, even without any connection. No speakers, no rca input. I will test with a phone. Thanks!

[mwgrient]

there is stil hum, with or without rca / phone connection and if played music, I do not hear it until the volume is al the way down, then I hear the hum/noise again.

[Paul Birkeland]

So there's a sweet spot where there is little to no noise when the volume control is around the middle of its rotation? 

What kind of solder did you use when building your kit?  Did you use any flux or other products along with the solder?

[mwgrient]

I have bought it build, but have done so much since then that I consider it build myself :-)

See attached label for solder I used. I see a lot of brown spots on the solder. So It has probably flux or something else in the core of the solder. I use flux myself too on some points (flux Almit, T435).

[mwgrient]

I also use a soldering station with temp at 710/750 F. And see that the solder is expired??

[Paul Birkeland]

For some reason I can't open or view the photo, is there a product name/number with the solder?

[Doc B.]

Photoshop says the jpeg file has an "unknown or invalid marker type". You might try saving as a .png file and reposting it.

[mwgrient]

Hope you can see it now. Picture of solder and flux.

[Paul Birkeland]

OK, yeah, the brown dots are probably that flux you've added.  You might find it a lot easier to use a 60/40 leaded solder with rosin core flux in the solder, then you don't need the separate bottle of flux.

[mwgrient]

thanks, I have ordered just that.

[grufti]

The Fluitin 1532 solder is a rosin core solder. "DESCRIPTION - Alpha Fluitin 1532 is an activated rosin cored solder wire developed for general hand soldering applications. Fluitin 1532 is suitable for use in any commercial no-clean hand soldering application that specifies compliance to J-STD-004 – ROM1 standard." It's pretty standard useful stuff. There was never a need to use flux from a bottle.

[mwgrient]

Yes, I can see that on the soldering joints. mostly with a lot of brown color. But the solder label says it's overdue...

[Paul Birkeland]

Eh, solder doesn't really expire.  I've used solder that's older than I am.