OBSERVATIONS GM1SXX 14 Jan 2010
GB3CSB on 1296 and GM6BIG on 1298
In a recent OBSERVATION I mentioned that I couldn't copy GB3CSB despite it having been 'spotted' by the builders on the EU.BEACONSPOT website. . I had been expecting to copy the beacon at 'Rock-Crushing' signal strength at my QTH IO75UV since the beacon itself is fairly local at IO75XX. I revisited the frequency for CSB on 1296.985 and had a more detailed listen while slewing the Tonna Yagi around. It transpires that I *can* copy CSB, but in the words of the prophet, it's as weak as p**s ! On my ICOM PCR-1000 virtual receiver, it's right down there in the noise. I'm being blocked by a local hill, probably the one I can see out of the shack window, that effectively blocks me in the NNE-NE direction. By using headphones and 'tuning my gob' (an old Royal Signals trick learned from LA2QAA) I was better able to copy the beacon and heard it's CW Ident and JT data. So for me at least, it's there, but VERY weak indeed at my QTH. The beacon uses a flat panel antenna beaming 150 degrees but even so, I expected it to be a lot stronger at my QTH. The offending hill is on the Barshaw Golf Course near my home. It does a good job of blocking most VHF/UHF signals to the NE-NNE of my QTH. Bloody hills! If I want to listen to the RSGB News on 2M from Bearsden of a Sunday, I have to be upstairs, and even then, it's VERY scratchy. I usually don't bother because it's just too much 'work'.
I retuned the PCR to 1298 and had a listen for GM6BIG's personal beacon which I use as an easy reference. It was absolutely booming in, stronger than normal, but without the usual portamento effect. I strongly suspect it's been revamped over the holiday period with a DDS core because IMHO it's simply not possible to produce clean FSK on 1296 using a varicap. Varicap driven exciters always have a 'charging curve' that leads to some frequency pulling.
I'm led to believe that the other two beacons in the cluster will come online sometime in the next few months.
73 Al.
GM1SXX