Dummy load/watt meter


howard winwood G4GPF
 

As these QRP kits are low power a lot of the commercial SWR/Power meters will not read these low power levelsand when they do they are not overly accurate.
May I offer a suggestion which involves a little construction work (but that is why we are building these kits, because we like to).
There is a great book recently published by ARRL called "Microcontroller Projects for Amateur Radio".
It contains, among others, a dummy load/ Power meter, it is VERY easy to build and if you follow the coding instructions, quite accurate.
The book is available from RSGB too and an Amazon Kindle version is available at less than half price.
It is a fantastic book, No! it is not cheap, but well worth it in my opinion (especially the Kindle version)
I have already built a dummy load using the same idea as in the book so just needed to build the electronics.
Very simple, an Arduino Nano, 0.96 inch OLED display, 2 resistors, 1 capacitor and 1 diode is all it needs.
There are only 5 pins used on the Nano, 4 of these go to the OLED display, the other is an analogue input to measure the dummy load RF voltage.
All the code is in the book (there isn't a lot of it so simple to type in) and worked first time.
So add this to your "I must do " list, it is well worth it.
Hmm! what other projects in the book do I need???????

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