Gassy nightmare

Ok, title isn’t very appealing. I know, however it truly reflects what I experienced over the past few days. Let me clarify before I start: a gassy tube developed a nice fault-finding journey. You always learn a lot from all this, for sure. Luckily, due to the holiday season, I had the time to work on this. I’d rather have spent it otherwise, but my 300B amplifier was dead.

6BY5-GA damper

I had a gassy 6BY5-GA damper rectifier tube. I should have changed it, but I was lazy and I paid the price for it. When turned on the 300B HT power supply, it will flash blue for a sec or two and the gas ionisation will disappear after a minute or two when tube was warm enough and operated as expected. Problem was that my stash of these damper tubes was up in the storage, who knows where.

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300B Amp: the journey starts here

I can’t get away from my big HT power supplies. This time the HT +400V for the 300B amp is here. Lots of Lundahl iron and a lovely hybrid bridge made of mercury rectifiers and damper valves. Yes, I’m in love with the blueish colour of the 816s. Despite they are mercury rectifiers, I know.

I promised the wife I’d get a smaller amp, that was my excuse for the 300B reference system. Still this is not going to be small, however, it will be compared to the 814 SE Amp!