• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

WOW, I want one !!!

It has a +-3dB between 30 and 15kHZ. Loads of mercury vapour rectifiers to look at. Not the easiest repair job due to the weight! As a Philips Authorised Repair Service Centre many years ago, I has one in for service. It was modified to use silicon rectifiers as the MV rectifiers were no longer available at a reasonable price.
Always have one of your hands in your pocket to reduce the risk of electric shock. The original amplifier would give the engineer a facial sun tan from the UV produced by the MV rectifiers and definitely a head ache from them.


2002-08-15 10:16 pm
I'm sorry but without those flashy mercury vapour rectifiers its just not floating my boat.
Flashing purple bulbs with a free suntan is just so much cooler ;)

Open oil bath transformer cooling - every DIY build needs some of that.

I actually have a neighbour friend who has three phase, so I will have to point him in the direction of these (though last time we talked we both agreed that 10W was overkill).

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and it can regulate supply voltage too! How cool is that


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