K3MSB

Using HM-102/2102 Meters in an SB-220



Below is how to determine the shunt and multiplier resistances to use a meter from an HM-2102 VHF wattmeter in an SB-220.



I have tried this and it successfully works.

The above measurements were what I measured using an actual meter. Here's the ideal data:

The SB-220 Plate Meter, SB-220 Multi-Meter, and SB-200 Meter are the same meter movements: 1400 ohms, 200 uA meters. 1400 ohms x 200 uA = 280 mV.

The HM-102 HF Wattmeter and HM-2102 VHF Wattmeter are the same meter movements: 1000 ohms, 100uA meters. 1000 ohms x 100 uA = 100 mV.


Copyright (c) Mark S. Bell 2017