Bias Monitor Cable Kit
Got a BF amp or a clone of one? Got an amp with some extra holes in the back panel? Got a decent voltmeter? If so, no need to spend 100 bucks on a bias rite. You can install this kit and measure the idle current in the outputs. For BF amps, you install the jack provided in the hole that has the ground switch. That way, you don't have to muck up a vintage amp by drilling a hole in the chassis.
Here are instructions that may be applied to just about any amp. The cathode of most octal power tubes is on pin 8 and for most 9 pin tubes it is on pin 3. You install 1 ohm 1% resistors between the cathode of the output tubes and ground, then take a sample of the voltage across those resistors to the jack you installed.
Anytime you want to check the idle current, you simply plug your voltmeter into the jack using the cable you'll build with the parts we provide in the kit.
It couldn't be simpler. The kit includes a stereo jack and plug, so you can do one, two (independently), or the two sets in a quad, and on up. In other words, both sides of a push pull. The kit includes stereo jack, stereo plug, two 1 ohm 1% 2 watt resistors, banana plugs, wire, and three conductor cable.