wiki:TubeBiasMonitor

Version 14 (modified by Eric Hazen, 2 years ago) (diff)

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Built a board

11/8/20

Stuffed board, trying to test. Completely screwed up the programming connector. It's a 2mm pitch numbered wrong. Managed to wedge in a 2x3 header, can maybe fix the pinout with a knife.

  MISO (18) -- 1   2 -- VCC
   SCK (19) -- 3   4 -- (17) MOSI
  nRST (1)  -- 5   6 -- GND

Parts ideas:

  • INA126 instrumentation amp powered on +/-12V WRT local GND
  • 3.3V Arduino mini
  • 16x2 LCD display e.g. https://www.sparkfun.com/products/255
  • Power:
    • 5V or 3.3V floating converter for Arduino and logic
    • PDM1-S5-D12-S
    • PDM1-S3-D12-S
      • +/-12V DC/DC converter (5V or 3.3V input) for INAs.
  • couple of buttons?

Box:

INAs would measure the four bias voltages. Additional channels would measure the DC offset from GND of the cathode circuits on each side.