Forty9er QRP CW TRX

Forty9er QRP TRX

I had noticed cheap kits from china for the Forty9er. A project originally designed by the NorCal QRP club. The Chinese kits cost £10 with the PCB and all the parts. Which makes a nice little project. They are advertised as being 3 Watt output. The reality is just over 3 watts.

The kit had good instructions and included a circuit diagram. A resistor and capacitor was missing but there were extras for others. I have a draw with bits and pieces in. So the missing parts was not a big issue. This kit does require the builder to wind a couple of inductors. Its not difficult and instructions are included.

The wave output looks clean and is stable. Its crystal controlled. So this is expected.

The Frequency plot of the output looks good. No meaningful harmonics can be seen.

A lot of people have said these kits dont reach the advertised 3 watts. The above image shows mine being driven into a dummy load. It is putting out 4 watts.

I decided to build a battery pack to power the forty9er. Which contains 3 parallel 18650 battery holders. All connected to an 18650 charger. This increases the current capacity and puts out just under 12 Volts.  The charger will charge the Cells when power is applied. When power is drawn it will supply power. Its very light weight and small.

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