72 brownie wrote:so does this knob raise/lower voltage or increase the rate at which it sends a signal? my gauges are reading properly now but i just want to know for my own benefit
You are on the right track!

This unit is called a Instrument Panel Voltage Regulator (IPVR) it controls the voltage to the gauges.
The gauges are all based on the old 6V systems from the past so they just added the IPVR to cut the 12V down to 6V after they went to these new fangled 12V batteries

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The IPVR works by cutting the voltage in and out (On/Off - Pulse) at a speed/rate to make it look like 6V average. So YES you are adjusting in the Pulse rate but it also, and more importantly, is adjusting the Voltage, so that the scale of the gauge calibration works correctly.
(side note: this makes a DC square wave signal to the gauges but the pulse is not seen at the gauges because they don't react fast enough to see it

)
Hope that was a simple enough explanation for everyone
