Hamradio stuff

RedPitaya SDR project

I use RedPitaya as my base-radio for my 10GHz EME.

My setup is:

Redpitaya + g4ddk transverter 29/144 MHz / Kuhne MK2 transverter 2m/3cm

I had some issues on 10GHz with frequency stability so i have made a new LO for my G4DDK suffolk transverter using 1ppm oscilator. Another issue is the 125MHz oscillator on RedPitaya, at powerup it drifts at few Hz/minute. I plan to modify this and to use external reference-locked source, mod is describet here.

Guys from RedPitaya were so kind to give me the Audio codec. The schematics - how to connect codec can be found here.

WM8731 Red Pitaya
SCK --- DIO4_N (E1) Pin 12
MISO --- DIO5_N (E1) Pin 14
MOSI --- DIO6_N (E1) Pin 16
ADCL --- DIO7_N (E1) Pin 18
SDA --- (E2) Pin 10
SCL --- (E2) Pin 9
3,3V --- (E1) Pin 1 oder 2
GND --- (E1) Pin 25 oder 26

source: http://forum.cq-nrw.de/viewtopic.php?t=129  and  (from the same source)


For the EME digital modes i use PowerSDR and WSJT-X. The commands between the two are sent via Virtual serial ports (VSPE emulator) software.

Audio is transfered over VB-Audio virtual cable.

In the future i plan to discard the 28/144 xverter and to try with oversampling and filters. In order to be able to do so, i need a version of RP without installed LowPass.



VK7UM - S57RA / 16.386km contact with only 60cm antenna

After some effort - moving air-gun and extending tx waveguide, rx and controll lines, we managed to make a contact on 10GHz with Rex - VK7MO from Hobart/Tasmania. We repeated the contact the day after with smaller antenna and less power on his side. 

First day Rex used 120cm antenna and 90w and day later only 60cm antenna and 50W. Equiment on my side was 3m dish, abt 150w at feed, 0.8dB preamp, kuhne xvrtr and RedPitaya and PowerSDR radio.

Distance between stations (jn75ap in qe36wv) is 16386.66Km.

Echoes from the moon on 10GHz

Autumn 2017, new 10GHz setup, 400W power amplifier, SDR RedPitaya radio, 1.4dB preamp. See more photos or listen to the Moon echoes in the Video...