Zur DUR Treffen am 9.10.2009 habe ich einen kurzen Vortrag zum VNWA2 gehalten. Der Teil ueber die Messungen erfolgte praktisch und ist deshalb im Vortrag etwas kurz gehalten.
At the DUR meeting on 2009/Oct/09 i held a short talk about the VNWA2. The part about measurement’s was a live practice and therefore only covered in the slideset shortly.
Slides in german language only.
Last weekend i participated in the UHF/SHF Contest within the DM7A team from JO60LK (Fichtelberg). The day’s before i completed my laser station. (Mechanical stuff for adjusting the laser diode and modifications for getting modulation working). A first test via reflektion at a house in 500m distance was promising. With Marcel DK5WMA a sked was arranged for saturday afternoon. I mounted the laser transceiver at the Fichtelberg. Marcel’s QTH was the Hirtstein in JO60OM. I adjusted the telescopic sight to the prominent wind wheels at the Hirtstein and switched on the laser. Marcel was able to see the beam immediately. How crazy. The sun was still above the horizont. The test from JO60OM into my direction did not work at first and we decided to wait for sunset. We tried again right after sunset and after some minor adjustments at Marcel’s side the twoway connection was working properly. Amazing to hear the voice over around 20km distance. We both took a photo of the red dot at the other side. Obviously DK5WMA’s camera is much better ;) See some photo’s below.
Laser in JO60LK
DK5WMA as seen in JO60LK, my camera is not that sensitive.
Laser as seen by DK5WMA
Two days before the next contest at least the mechanical work is almost finished. First tests looking promising. There are still problems with the modulation of the transmitter. Let’s hope for good wheather at the weekend.
Laser Transceiver
I was once more QRV from the Triebenberg in JO61XA. The activity was a bit sobering but at least the wheather was nice. I got 13 QSO with a ODX of around 100km. Surprisingly there were some local stations active in FM on 1297,5MHz. The week before the contest i modified the transverter to solve the thermal problems with the built-in PA. This works quite well now without running away 10kHz anymore. Additionally i repaired an old 16Ele Yagi i got from DG2DWL. This antenna is around 6dB better than my old bi-quad. The biggest surprise came 15 minutes before the end of the contest. A beep from the voltage converter that supplies the antenna rotor told me that my car’s battery was empty. No chance to start the engine anymore. It was the first time i was happy that there are so much people hiking at the Triebenberg (and of course coming by car beeing able to help me starting my own one) ;)
Hear you next time !
Transverter, FT857D and voice keyer inside the car
In order to get the laser communication unit justified for the correct direction it is necessary to have the possibility for fine adjustment of horizontal and vertical angles. I made some progress in building a unit that can be mounted onto a tripod and will cary the laser transceiver in the future. Find some pictures attached below. It’s not finished yet but the horizontal adjustment works fine.
Laser justification unit
Laser justification unit
I participated in the July DUR Activity contest. This time i decided to be qrv from the Triebenberg in JO61XA. Because the hill is not open for everybody (there is an external laboratory of the Technical University of Dresden) i had to build up the antenna at the base of the hill. The Triebenberg is the highest hill in the area of the city of Dresden. The activity during the contest was much better than last time. This was mostly because of the OM´s from DF0MTL beeing active from JO61JF. Therefore i had only few time for 2m operation but i had only a bigwheel antenna with be anyway. At 23cm i am still using my tiny hybrid-quad antenna which appears not to be competitive ;) Next time i might use another QTH and another antenna, of course. After the contest i had to hurry up because the rain front came close really fast. Two minutes after i had all the stuff in the car heavy rain started.
Hope to hear you next time !
Tiny antennas in JO61XA
Dark clouds over the Triebenberg
DL2CH transmitter and optical sensor
Testing optical communication ...
Today there was another DUR activity contest and i used it to test some equipment. Because the OK/OM activity is in parallel i tried to setup my 2m Tonna yagi. Surprisingly this was a easy job. The only problem was that asseble the antenna took much longer than expected.
The activity on 23cm in the DUR test was low. I had 5 qso only. But i did some qso on 2m as well. ODX was a 9A station. I also heard a french station and some german’s calling a EA station. Maybe some sporadic E ? I did not hear anything from Spain.
For 23cm i have to build a bigger antenne until the next test. The single hybrid quad element is only good for some local qso.
DH5YM in JO61RB
all the equipment
After long time thinking about it i started to build up my laser station i edged the PCB´s today. The parts are on the way from the distributor. The diodes are already available here (2x 10mW, red). I also buyed some lenses in the past week. The biggest problem seems to be the mechanical fixture for fine adjustment of the direction of the 3 different optical axes.
Laser TRX PCB´s (DL2CH Design)
I tried to participate in the activity day of the “Dresdner UKW Runde” (DUR) last sunday.
So i drove to the Bayerhoehe (JO61RB) which is some km west of Dresden close to Wilsdruff.
Testing the equipment one day before gave me a good feeling but unfortunately the RX/TX relay of the transverter did not switch reliably with the 12V battery supply.
So i was just able to do two qso. Also the antenna was a bit tiny. So i have to look for a small Yagi before the next test. What worked fine was the antenna rotor driven by a 12V to 220V switched converter.
73s de Mario
DH5YM in DUR test from JO61RB
