+ + + - D L 4 X A V - jo 43 xn - h a m b u r g , g e r m a n y , e u r o p e , e a r t h + + +
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The FA SDR KITs are easy to build, the price is moderate. you need a computer with stereo soundcard and SDR-software. My VR-5000 has a 10.7 MHz IF out connector, so i ordered the 10.7 MHz IF version. at the moment i use baudline as a bandscope. software demodulation is possible with other software, for example linrad.
here is howto change SDR KITs for 600 KHz, 21.4 and 45 MHz IF (geman language).
the local oscilator of the SDR KIT laecked into the receiver. in AM an FM mode its no problem, but in SSB i heared a continius carrier. first i tried a 20 dB atenuator between the IF-out and the SDR-kit, the carrier diapeared but now the signals ware to weak. after some experiments i placed a 2 stage IF-anp between the RX and the SDR. now the sensivety is good and the carrier is below the noiselevel of the RX.
SDR KIT in a box with 2 stage IF-preamp
in the small box.
inside view
The VR-5000 has a fast AGC that you cant switch off, so the IF-out is always leveled and the dynamic range is reduced to about 40 dB.
cheap soudcards have a minimum dynamic range of 80 dB so a RX without AGC would be better.
dual use of a SAT transponder - military data signal and brazilian pirates in FM
RTTY sigal on a transponder

home rig sat ant qsl info feedback links homebrew H F V / UHF disclaimer

dl4xav 2010