I had a lot of fun last weekend in EA PSK63 Contest. Members of S55W contest team have a lot of RTTY experience but contesting with low power PSK63 is another story. We were very pleasantly surprised how 50W are just enough for a great race. And we were not so impressed with some distorted signals on the band.
Žane, S57CT, Kristjan, S50XX and me (as official ZRS examiners) were very pleased to promote 17 new radioamateurs on 20th of February at Radioklub Ajdovš?ina S59AAN . They all passed N class exam. Congrats! Soon they will take part in another course and we’ll greet fresh bunch of full licenced hams on all bands!.
Radioamateur high speed data links in my area are underutilized We have several webcams (capable of streaming H.264) , some servers, APRS gateways, a very busy Skimmer connected to dx cluster network … but all this rarely generate more than couple of Mbit/s. This evening I combined Raspberry Pi with USB DVB-T dongle into high performance network traffic generator. The initial idea was different I wanted to experiment with SDR stuff on R_Pi. I compiled rtl-sdr from osmocomSDR (http://sdr.osmocom.org/trac/wiki/rtl-sdr) . My USB DVB-T fob is a Sencor SDB522RT , a simple gadget that works well under various operating systems. After plugging-in the USB dongle I started rtl_tcp (with parameter -a and IP address of R_Pi … otherwise rtl_tcp defaults to localhost IP) and fired up SDR# on Windows7 machine. Selecting “RTL-SDR/TCP” as a source and configuring IP address of R_Pi before pressing Play was enough to connect SDR software to remote “converter”. Sample rate of 2048000 samples per second (about 2 MHz “window”) generates about 33 Mbit/s or 4.1 MB/s of network traffic … and this could be used in performance network testing
Raspberry PI with rtl_tcp feeding data to SDR#
Upper right window is a SSH (terminal) session with R_Pi .
Last EUHFC contest from my summer location JN65UX was not eco-friendly. I don’t have grid power here (yes, I’m posting this from nice cool porch 😉 ). The cabin is solar powered at for least two decades now but this is still an ongoing project. I pulled out old 1,5 kW chinese generator because my new inverter make all radioamateur band useless. Normaly I work QRP directly on 12V house wiring, but EUHFC doesn’t have this category. So for 12 (plus…) hours I polluted the peaceful wood with monotone brbrbrbrbrbrbrrrr.
It’s time to find a solution to RFI inverter problems and first results from today are very good.
Before the noise covered all bellow S 9 +40 dB on 80m band
With filter … wow … I can follow the S5 net on 3,605 MHz … 160m is still useless, 80m could go for local traffic and big contests, 40m also …. but 20m and up are completly clean!
Not for producion use 220 V contacts are exposed during the tests! .
RaspPi is now “entering production” at s56g/p site. First tests were successful and tiny computer runs javaprssrvr (no RF stuff at the moment). WX station is also planned soon. The most amazing thing is very low power consumption.
I ordered Raspberry Pi (Farnell) on 1st of March, 2012 … and little creature arrived yesterday (29th of May, 2012). I have rather busy schedule this week but few minutes were strapped here and there to first switch on the toy There is no remote access configured on debian image and I connected RPi to the only HDMI display in the household. Looks amazingly well Â on 45″ monitor 😉 With ssh daemon started and powered with HTC smartphone charger now runs as a “headless” server on home network.
I was offered to join small group of “students” visiting this year’s Montichiari Contest University Italy and there was no second thought 😉 Gregor, IV3WJP, decided to be a driver to 3 youngsters : Paolo, IV3BCA, Mauro, IV3AZV and me. I had a great time, MNI TNX guys!