30
Jul
'17

From a bunch of stuff some other ham wanted to throw away, this ex-SWR meter.

Stripped

I have no idea why the Dreaded Previous Owner stripped it down to this state. The meter movement is fine, 950-ish mV over a 4k7 resistor gives FSD, so it’s a 200uA unit.

inside

The detector components are still in place, and it looks very similar to the Micronta 21-520A except that there’s only one meter. There’s also a little bobbin on the side for an antenna, presumably to make it into a Field-Strength Meter, but that’s a gimmick and won’t happen.

NewSwitches

The junkbox yielded two switches of the right type and size (one selects Power / SWR, and in SWR mode the other selects Forward / Reverse). There will also be a pot to set FSD in Forward mode after which the Reverse mode should give the SWR. Give or take. Don’t expect a lot from meters like this.

Fast forward a bit and we have

IMG_0070r

IMG_0068r

Don’t ask me what used to live in those two extra holes. This setup works for me, for the price of a few junkbox parts and some time.

 



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