Wattmeter with dummy load for QRP test

I just built a simple dummy load (8x100 ohms) with a sample RF (schottky diode 1N5711 and capacitor 10nf).

There are a lot of commercial schemmes about It to use with a multimeter. I fit the PCB and a voltimeter into a case and this is the result.

I think It Will be very practical for testing qrps on lab.

It is a low cost budget, not more than 5-6€.


A few years ago I built a similar one designed by AA5TB

The thing I liked about his design was that he explains both how and why it works with instructions on how to adapt it for other meters etc. As a result I actually learned a lot while building it.


It is a great article, of course. I didn’t know It.
Thanks sir.

This sort of terminating power meter is easy to build and very useful. I have a collection built over decades for particular needs. Be aware that the diode you use will affect the calibration as will the load resistors. Both behave differently at RF compared to DC.

Power levels below 5 W need to be calibrated against a known reference. A simple circuit like this does have limitations.

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