Strain gauge (BF-350) + hx711 (always zero)

Did you read post#2.
There is a batch of green HX711 boards out there with a design/production error.
They don't work unless you solder a short wire between E- and GND of those boards.
You can identify them by holding the board against a strong light.
If the light shines through the board, then you have the one with the production error.

If you have a DMM (digital multimeter), then do this.

  1. hold the black lead to the metal of the USB socket (Arduino ground).
  2. with the red lead you should measure 4.25-4.30volt on the E+ and zero! volt on E-
  3. you should measure half of that (~2.15volt) on A+ and on A-
    Move the meter leads to A+ and A- and choose millivolt range
  4. you should measure less than 20 millivolt between to A+ and A-

Leo..

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