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  1. E

    Solid-state audio amplifier complexity vs valve/tube

    This posts aims to get opinions about why solid-state audio amplifier circuits are almost invariably much more complex than valve/tube amplifier circuits. One could think that, if a good tube circuit is just redone, susbtituting each tube by a transistor (common cathode by a common...
  2. E

    Measure 500V DC with digital scope and 100:1 probe

    Hello everyone. As this is a safety issue, and I'm not sure, I would like to ask instead of experimenting. Most digital scopes state a maximum input voltage of 300 V RMS. I want to make some quick measurements on a live tube amp circuit and its power supply, which may go a little bit over that...
  3. SGiard

    Buying vacuum tubes in Canada

    Hi, Can anybody recommend some sites where I could buy vacuum tubes online? Being in Canada, I'd prefer Canadian sites if there are any, otherwise U.S. sites. I did a preliminary google search but I'd like to hear from actual people who bought tubes and were satisfied with them. I don't...
  4. J

    Is there a procedure or general guide for replacing the CCFL tubes in backlights

    I have a wacom cintique 24HD, an expensive monitor i got fairly cheap in a scam of sorts, i was sold a dying monitor, the tubes are on their last legs, they only really reared their weakness once it got really cold, which took a while since we had unseasonably warm weather from since i bought...
  5. B

    Electronic Tubes

    I have a problem finding information on some tubed I have I have 6 big National Tubes NL-6989-NE The Tubes are new and because of their size I thought I could make some kind of cool display. The tube has a high voltage cap on the top and printed on the base along with the tube numbers is...

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