I scored something but have been very quiet here lately...
I've been going nuts with the tube stuff. I'm actually considering selling off bikes to make space for amps/parts/tubes...never thought that would happen!
Here's the beast in question...it's an Altec 353A from 1959...yes...1959. How it's in the shape it's in is baffling...but...
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Glowy tubes...all the soldering for the most part was original, even the wax marks on the solder joints from QC still. Unfortunately when I powered it up after doing what needs to be done to old electronics stuff (DON'T EVER PLUG IT IN AND JUST TURN IT ON!), I cautiously powered it up and discovered the power tubes were red-plating...which means they're exceeding maximum thermal dissipation limits. I wasn't pleased but trucked on...
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And here's something interesting I never seen before...electron glow on the glass of the tubes! This phenomena happens when the electrons are at such a high velocity that when they strike the glass they liberate phosphor atoms from the wall of the glass and cause it to glow because of the gases formed. Not a bad condition and eventually goes away but it looks really cool! I haven't witnessed this yet because the power tubes run on 380V...nothing I have made does that!
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I think I ironed out all the bugs...think...I know that's not true! I should really replace all the resistors as I found a few bad ones pushing the grid bias up on the power tubes causing the overheating.
I had it cranked a couple of times. A 30WPC tube amp capable of 50WPC is gloriously loud...and...sounds like the performers are literally right in front of you. Unreal! I love this thing! It has humbled me a bit and pushed me to research my own equipment so I can get that same effortless, live sound too.
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