I came across this video, by accident on Youtube of French radio amateur, Claude Paillard ( Callsign F2F0) who makes his own valves by hand in the traditional way. It gives you an idea of what it takes to make your valves. He is making a triode so if you do this twice and put in one glass tube you have an ECC81 / ECC83/ ECC99. The video is made in France so the few […]
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I have come across a bit of a mystery regarding Svetlana valves ( tubes) and perhaps some readers could explain. Svetlana valves are made in Russia and are good quality products. My understanding is that an American corporation owns the rights to the Svetlana so the company JSC Svetlana lost the rights to use the Svetlana name. JSC Svetlana made their valves in St Petersburg in Russia and adopted the Winged C log with C
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Amplifier valves get hot and there are very high voltages present, so make sure the amp is switched off and and the valves are cold. Hot amp valves can give you a bad burn ! The output valves , the rectifier, and ECC99’s all get especially hot ! My most recent burn was off the little output valve in the picture above, the EL84 output pentode The first basic question is how often to replace
Steps to follow when changing your valves in your amp Read More »
I offer 120 day warrant on valves ( tubes) . Why is this so great and why dont valves have a one year warranty like everything else?
“Why don’t valves ( tubes) have One Year warranty ?” Read More »
Rectifier Valve ? Many of the vintage amplifiers such as the Vox AC30 , Fender Twin Reverb use a rectifier valve. Other amps use modern silicon diodes. The rectifier valve ( or diode) is a key part of your amplifier’s power supply. Its job is to “convert” or rectify the AC voltage coming from the transformer into the high DC voltage needed by your valves in your amplifier. The output valves need the highest voltage
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I thought this looked like a really useful table on bias current for output valves. The top of the page allows the super techie types to do an exact calculation based on measured voltages in your actual amp and the configuration of the circuit. The featured picture is actually all the tools ( apart from the right screwdriver). It is simply a multi-meter and a special adapter. You plug the adapter into the output
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