When fixed bias is used in your amplifier, the currents need to be adjusted frequently due to aging of the tubes, or variations of the mains voltage.
To solve this Tentlabs and Ir Bureau Vanderveen developed this "Automatis Bias Module".
- Output voltage range to grids -2V to -85V or -2V to -160V
- Output sinc & source current max 1.5mA
- Input mains voltage 115Vac or 230Vac (+6% / -10%)
- Input range high voltage sense: 200V to 500V
- Total size 100*100*40mm (W*L*H, standoffs excluded), can be separated in 2 equally sized boards
- Hole pitch 91mm * 91mm (symmetrical)
- Total size separated boards 49*100*40mm (W*L*H, each board, standoffs excluded)
- Hole pitch separated boards 91mm * 40mm (symmetrical, each board)
- Hole size 3.5mm
- Weight 375 gram
Tentlabs Negalive Bias Supply Application Notes (PDF)