JUMA DFR1 Direction Finder Receiver

JUMA DRF1 is a stand alone direction finder receiver for 160 and 80 metes.
It is designed for interference finding but it can be also used as a general receiver on the go.

Click DFR1 picture to enlarge

The antenna is a four turn magnetic loop made of two layer FR4 PCB which provides good sensitivity.
The two band DSB receiver is implemented in the handle
with a 9V battery and a small speaker.
Best listening experience
can be achieved with phones connected to the 3.5mm jack.

The antenna is
mechanically very symmetrical and the coupling is electrically very well balanced
which provides very deep minimum during direction finding.

The tuning of the magnetic loop and the VFO is using capacitance diodes.

The directivity is best for ground wave signals like near by interference sources.
The signals coming via ionosphere have many arriving angles which means
lower directivity.
Documents download (PDF ans Excel)
Schematics PDF
PCB top layout PDF
PCB bottom Layout PDF
Front panel PCB PDF
Part list Excel

Update 2019-07-07 OH7SV

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