Sunday, March 8, 2009

Social Networking and the pileups, plus image rejection revisited

Last night I stayed wayyy tooo late, working DX. Well make that trying to work DX. I was hearing every one fine, I just mostly couldn't pound through the QRM. I heard KH2 Gaum, FK8 New Caledonia, H40 Temotu, ZL7 Chatham, KH0 Mariana, all coming through FB. My problem was I couldn't breach wall of RF coming out of Japan. All of these guys were running Japanese like crazy. There were virtually NO US stations calling save one K5 going toe to toe with me calling Guam. Neither one of us got him. A lot of these DX stations were working simplex, so there was no real pileup, but I just couldn't break through. The truly maddening thing was I had almost no propagation to Japan (they were still about 1 hour out of the picture) so I couldn't hear or see the competition. I was flying blind.

On the H40 there were quite a few US stations as he was on early in the evening, but the others were on between 3 and 5 AM. After a while I stopped calling and just watched the nature pf the pileup and low and behold I started seeing some people I know calling. I saw W9KNI and a few others. Earlier in the evening I worked ET3 Ethiopia. I sat and watched that pileup as the terminator started approaching the ET3 (almost sounds like something out of a schwarzenegger movie). I wanted to see if propagation was going to improve on him, and about 45 minutes after I worked him K3RR worked him. He did get louder as the grey line approached.

I therefore knew Joe was at the rig trolling for DX. I had a similar experience a few years ago. Joe and I had gone our separate ways in our lives. I was inactive for about ten years. I had the rig and antennas all hooked up, at that time I was using a FT-1000D. In the mean time I bought a Pegasus. I had a blast with that little radio. The RX wasn't very good but it was just fun to play with. One night I heard a Russian who was doing some work in Iran and somehow wrangled permission to get on the air. The Russian signing /EP Was blasting through on 80M that night. I gave a half hearted attempt, but I started listening to the pileup and low and behold there was K3RR working the guy. Wow. I looked up Joe in the EHAM data base and shipped him off an email and our friendship rekindled like we never lost a day.

Last night when I "saw" Joe in the pileup, I fired off an email, and we met up on the low end of 75, a little above the SSB band edge. The contest had not drifted down that far. Normally I wouldn't even turn it on during a phone contest weekend, but just watching the pile, gave me the info I needed to have a nice QSO in a nice clear part of the band where neither one of us would ever visit, while the helots were up the band raising helot hell.

When I was at Orlando this year Gerald had a pic of a PowerSDR console that included social networking as part of its character. His son Matt has been working on the development. The console had a means to connect to the Internet and your buddy list was shown. This way you could know if your friends were on the air, or in the shack, or otherwise available, basically the same as a Yahoo account or a gmail account. I spend a lot of time tuning all over 160 80 40 and 30, mostly just listening to CW QSO's but it also would be nice to know when my friends were available and to be able to chat with them in a chat window for example in the heat of battle, or let them know when I hear something they need and vis versa. I'm sure there are a dozen other uses for such an idea, I'm stodgy and old and not very creative, BUT the "YOUTHS" of today are not stodgy and old and are amazingly creative, and this kind of technology, the technology of social networking, Chat, SMS messaging, Facebook, Twitter etc is part and parcel of their lives and I see it very easily could be part of the Ham radio experience as well.

Yea Yea I know "You gotta have a Knob" and other old fart stuff like that .... And you wonder why Ham radio is dying. You know I saw a really good article in QST about how to solder a coax connector..... but you needed a couple hundred bucks of crimping stuff to do it.

Here is the scoop on the new image rejection algorithm hot off the presses from N4HY. Recall the RX in PowerSDR is basically a phasing RX. It works like a phasing TX in reverse. So how good your rejection is, is determined by how good your cancellation is. The TX part of this protocol is soon to follow!!!

Here is a preview:

"Non linearity introduced on purpose in a system hailed by all for the linearity and signal handling capability of its front end seems at best contradictory, at worst, immolation!"

I love Bob's hyperbole (mostly I just like using the word hyperbole in a sentence :P)

http://n4hy.blogspot.com/2009/03/image-rejection-along-road-less.html

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