What a lousy Sunday! Everything that could go awry, went awry. All my computers crawled to a halt (thanks FireFox), the MoveII telemetry software wouldn't install, nasty interference on both shortwave as well as 2 meters, Wxtoimg wouldn't decode weather-sat images even though signals were great, but what made me maddest of all was this....I tried to connect the ICOM IC820H to my computer. The CAT part worked, but not the audio IO. I tested the PTT and put some RF in the 70cm X-pol Yagi, after which it wouldn't receive anymore. SWR was 2.4:1 all of a sudden and no reception at all. Now I have to start troubleshooting another problem for which I don't really have time. And I was so happy that everything was working well.
Luckily I didn't put RF in the 2 meter yagi and luckily the evening pass of Fox-1D was a good one and netted me 80 DUV frames, which means I'm back at position 177 again (last time was Nov 19 of last year). Then when typing this my CMS acted up! Aarggghhhhh!
After five days of sporadic listening it seems that I really need a pre-amp for better 70 cm reception. There are signals coming in, but meagre at best. For telemetry reception a substantially louder signal is needed.
Had some luck on 2 meters today. Got a positive ID of the MOVE-II sat on 145.950 MHz. Every 10 seconds a beep and after three beeps a CW ID. Also some telemetry, but I haven't got the decoder installed, yet, so that will have to wait till next time.
The MOVE-II site is a really well made one and they even have a Linux decoder for telemetry. Unfortunately no other use of this satellite for us amateur radio users.
Good enough weather in the afternoon to put both the cross-yagis back into the tower. This time my sweet wife was helping me out with the lifting work. After some elbow grease they were proudly pointing at the sky again. Tested them out and heard/saw signals from CO-65, CO-66, Lilacsat (all new to me) and strong signals from FO-99, all on 70 cm. On 2 meter I monitored two Fox birds and got over 50 DUV frames to boost my score on the leaderboard. Everything seems AOK this time, so let's start enjoying.
My first satellite QSL card from the good folk at the Max Valier school. It's still my 'go to' beacon for testing 2 meter satellite reception.
Miracles do still happen. Lots of rain today, so the power lines were quieter as usual. My newly installed end-fed picked up lots of stations in the ARRL SSB contest on 40 meters at night and despite an awful SWR of 3:1 I still managed to work some stations; the first time I've been on HF in over a year!!! Two CA stations, two Japanese and two Filipino stations in half an hour. Not bad and even my wife was surprised that I took the mike and went on-air.
7153.5 1132 K6NA 59-CA / 59-100 (Glen from near San Diego)
7181 1132 JH4UYB 59-KW / 59-100
7196 1140 NO6T 59-CA / 59-100
7176 1143 DU3T 59-500 / 59-100
7171.2 1147 JE6RPM 50-? / 59-100
7179 1159 DU3ZX 59-500 / 59-20 (after tuning forgot to up my power)
Very good signal from the FO-99 Nexus CW beacon on 70 cm. Came in 20+ dB above noise level, so very much readable. Heard them on the 22nd, but not as good as this time.
Transcript: js1yav nexus 030065808E000178010101100a00d6ff9900530180015d
AO-92 was a disappointment, though. Hardly 20 dB over the noise and only 4 DUV frames decoded.
The coax transformer of the 70 cm cross yagi acts fine when receiving, but not when transmitting, so I took it out for further inspection.
Starting to test the 70 cm yagi again. Two signals identified tonight: FO-99's CW beacon and Athenoxat-1, both on 70 cm.
Because of the disappointing performance of both cross-yagis I took them down on Feb 10. I started rebuilding the 2m one from the ground up and found that by removing D4, the front most director, SWR improved dramatically. I tried spacings for other designs and opened a QRZ.com thread about it. The conclusion: first off, the design I made using the VK5DJ software is for long yagis and mine is not (too short), hence the disappointing SWR and most likely also radiation pattern. After removing D4 I also removed the coax transformer stub and used a coax switch to switch between horizontal and vertical and the AO-91/92 birds came in full quieting; never heard them so loud. SWR is fine on both horizontal and vertical yagis, so I'll take it for the moment and keep on using the yagi as a 5 element instead of a 6 element.
The 70 cm yagi was a different story. I removed all the plasti-dip from the elements and the resonant frequency dropped a few MHz. I also re-balanced the antenna, although I actually took it off balance by moving the mast clamp to the back. This meant more coax lead and I routed the horizontal yagi lead to the back and got a perfect SWR in the upper 70cm band. The vertical yagi has an SWR of 1.5:1, which might be due to the influence of the rebar in the terrace floor. In a cross configuration the SWR is 1.5:1 now, so acceptable. For reception it doesn't matter that much anyway.
Today little success with the new antennas. Had a close pass of FO-29, but saw only faint signals which couldn't be decoded. Then I noticed some CW at 435.780 MHz and caught the following.....
Sunny and 25 degrees today, which is unusual for Chinese New Year. Put the finished yagis onto the tower with help of Tim. It took a little elbow grease but it was done by noon. Disappointment came when I measured the SWR at the antennas: the VHF beam was resonant around 139 MHz and the UHF beam around 441 MHz. Due to my design parameters I already guessed the UHF beam would be a bit high, but at 436 MHz SWR is 2.4:1 and that sucks. At 145 MHz the VHF beam also has a SWR higher than 2:1 which sucks even more, because when I took the last measurements before putting it up it was 1.4:1. It almost seems antenna building is a black art.
Monitored two passes of AO-85 in the afternoon, but both times signals were weak and only one DUV frame was decoded. CAS-4a also came in, although not with stellar signals, but at least I could hear JR6RM in CW calling CQ without much problem (nobody answered him). Before the depression set in I monitored the evening pass of AO-92. It went from south to north and the first 15 degrees of elevation were lousy. But then signals started stronger and they peaked at +30dB over ground noise. Never heard AO-92 that strong and over the whole pass I decoded 80 DUV frames, which is also a record. The last frame was decoded just above 0 degrees elevation and when signals were strong I could even hear the DUV tones humming from my amplifier. So for reception the VHF side is working well and that is a great relief, because I am more into listening than transmitting anyway.
And with 20 meters of coax between the antennas and the shack my rig-on-loan is still happy, because the SWR is around 1.5:1 in the shack. I know this is cheating, but still.....
The final stages: everything but the leads are mounted and most of the nuts and bolts have been covered in PlastiDip.
Lousy weather, so time to do something in the shack for a change. Finished boxing up the impedance stubs and mounted them as well. SWR 1:1 across the 2 meter band, which makes me very happy. Another thing to cross off the list.
The box that will house the impedance transformer.
After a lot of prepping classes I started late working on the antennas. I finished mounting the N-connectors on the alu-box and mounting that on the mast plate. Did some other small adjustments, but then dusk already set in and no time (and light) to take photos. Will have to wait till Monday.
Sunny and warm, so I cut some tubing and finished the vertical 70cm yagi. Unfortunately I ran out of element clamps, so I have to wait for BV6HJ to bring them along when he gets up north.
Luckily I don't go to Taipei often: an hour parking cost me 75 NT dollars, but I did find some LMR-200 coax cable, which was "only" 170 NT dollars per meter. Better than RG-142 which was 380!!! Still, I spent more money than I should have. The shop where I found the LMR-200 is called JMO and I almost forgot about them. They have everything a ham could wish for, as long as that everything is cables and connectors. The owner is very knowledgable and will go out of his way to find the right product for you. It comes at a price, because everything is pricey there. But better have a place where you can find what you need than being without.
Last Saturday night I started with the build of the 70 cm yagi. On Sunday I finished the mast clamp and today I had a productive morning where I drilled and threaded all the holes for the elements (56 in total). I fitted the mast clamp and the remaining element saddles and the result looks like this.....
Will have to go to Taipei tomorrow to get some extra aluminum rod because I don't have enough to finish the build.