JUMA DFR1 Direction Finder Receiver
JUMA DRF1 is a stand alone direction finder receiver for 160 and 80
It is designed for interference finding
but it can be also used as a general receiver on the go.
Click DFR1 picture to enlarge
is a four turn magnetic loop made of two layer FR4 PCB which provides good
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
The signals coming via ionosphere have many arriving angles which
means lower directivity.
Documents download (PDF ans Excel)
PCB top layout PDF
PCB bottom Layout PDF
Front panel PCB PDF
Part list Excel
Update 2019-07-07 OH7SV
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