The WM-2 from Oak Hills Research is a cool QRP wattmeter kit, which can measure forward and reflected power in three ranges: 100mW, 1W and 10W. With an accuracy of 5% of the full scale it should be possible to measure powers down to 5mW using this instrument. The WM-2 has a big, easy to read scale and can operate either from a built-in 9V battery or an external DC source.
wattmeter
OHR WM-2
Today I’ll start to assemble the OHR WM-2 QRP wattmeter from Oak Hills Research. I bought the wattmeter via the German QRP Project few weeks ago but I didn’t really have time to build it yet.