Early 2007 Nick Roethe DF1FO published V3.3 for his FJRX2 double super receiver. I obtained a kit and finished assembling it end of June 2007. Delivery of the kit is fast, the kit is of high quality and complete. What Nick not included are the parts everyone has in the junkbox or want to change anyway. On Nick's website all needed info is available, including the Assembly source code for the Mega8 processor.

Now ARDF/IARU style of fox hunting is not my kettle of fish. So I have changed the software.

I started out with the software from DC7GB, Tom. He had taken Nick's software and added a number of  features which I liked.

My "project guidelines" were as follows:

  • Leave orignal DF1FO principle and touch and feel of Man Machine Interface in place as  much as possible. I.e. it should still be a very nice ARDF Foxhunting receiver.
  • Add VFO mode, AGC on etc
  • Easy switching between DF1FO/ARDF and PA2PIM/FP (Flying Pig) mode.
  • All changes preferably in software. 
  • Hardware changes if needed must be very very limited.
  • Modified software must run in standard DF1FO receiver and provide original functionality.

It took a lot of work but the extra functionality is coded and still fits in the original MEGA8.

A detailed description of what was changed is in this pdf file: RP001_FJRX-2FP_V2.0_3.pdf

The source code and the hex file to program in the Mega8 together with supporting information is in:

A description and short operation manual are also included in the zip file

I still had some more wishes but ran out of space in the MEGA8. I swapped it for a pin compatible MEGA168 with twice the memory size. To differentiate it from the MEGA8in the FJRX-2FP the receiver is called FHRX-2FP.\