Palico 132 Posted February 23, 2017 Hey watched a quick video on setting the bias as I know I need a new set of tubes (on order now). Seems easy enough. Quick question. Since the Amp will be on and I know tube amps have enough amperage to kill you, been shocked by one before and scared the daylights out of me. Luckily just enough bite to scare me. Do you need to use a plastic screwdriver tip to turn the bias setting for safety? Or using a metal one okay as since it adjust away from the circuit board. Quote Share this post Link to post Share on other sites
spaceatl 1,976 Posted February 23, 2017 The trim pot is plastic, so a lot of things can work. I use a little plastic flathead with one hand and my other hand is behind my back. ;) Quote Share this post Link to post Share on other sites
Palico 132 Posted February 23, 2017 The trim pot is plastic, so a lot of things can work. I use a little plastic flathead with one hand and my other hand is behind my back. ;) It seems safe enuf with the position, just wanted to make sure that I put a metal micro screw driver on it was wasn't risking getting shocked Quote Share this post Link to post Share on other sites
psarkissian 362 Posted February 23, 2017 That's why trimmer drivers are plastic. Flyback transformer on a telly, bias trimmer on any high volt line, a plastic trimmer driver is a good idea. Yes, left hand in back pocket,... keep volts away from heart. No dephibrelating the heart while conscious and upbright. Be safe. Quote Share this post Link to post Share on other sites
oscarguitar 6 Posted February 23, 2017 I have never biased an amp before, but I've done the DT twice now. It's really not a problem. Very straightforward provided you are sensible and don't rush it. The key seems to be very gentle, small moments of the bias pots. Quote Share this post Link to post Share on other sites
Rowbi 5,373 Posted February 24, 2017 I usually use an electricians screwdriver that's insulated. It's usually one of the ones with a test bulb in it so the tip is small enough to fit the trim. Quote Share this post Link to post Share on other sites
Palico 132 Posted February 28, 2017 Thanks for the help :D , I got my new tubes in last night. 22mv on one and 26mv on the other so within the bias parameters. First time I've did Bias myself. Boy that knob is touchy, took a couple of times to dial it in. Glad I set it. It was 24 on one and 30 on the other to start. So make since on why I had so many problems out of that second tube. Quote Share this post Link to post Share on other sites