Ok, this is puzzling me. I've been playing with load cells for the first time, I have 4 cells connected through an HX711 as is apparently the customary practice. If I apply a load the reading from the HX711 changes so all appears well but I have two oddities I don't quite understand.
1. The readings are negative rather than positive, Google didn't give me a clear answer on whether that's expected or not.
2. The output with just the load of the empty weighing platform is either around -130k or around twice that with a small number of random data points outside that range. I captured a reading every second for an hour or so and this is what the trace looks like. There's two clear lines, one at X and one at x*2. What could cause that? If it were random noise I'd blame my soldering but this is clearly not random.
Any assistance gratefully received.