January VHF Sweepstakes 2010

I had considered trying to operate some from the WA4NZD club station in 4622, for at least part of the contest… Turns out that I didn’t, BUT I did go out there the week before with my new MFJ-269 antenna analyzer to check a few antennas. Here are some quick results:

The 6 meter beam (which only has an Armstrong rotation system) shows it’s best SWR of 1.1:1 at 51.8 MHz – which is plenty good for SSB. Most of the SSB activity I hear during these contests is between 50.130 and 50.200 MHz. We need to follow-up with more data points and see what the bandwidth curve will look like.

The 2 meter beam (which is a circularly polarized cross-beam type satellite antenna) shows a useful SWR of 1.8:1 at 144.7 MHz, which should be ok at 144.200 for the contests. It is likely optimized for satellite operations in the 145 MHz range. I noticed tho, it had a sharp dip down to 1.1:1 at 151.8 MHz, certainly worth the extra effort to sweep some points to construct a bandwidth graph.

The .7 meter antenna was not as forgiving tho. Again a circularly polarized cross-beam type satellite antenna, this shows the best SWR of 1.7:1 at 437 MHz (in the satellite sub-band). I would NOT recommend this antenna for a terrestrial SSB contest as the SWR of 5:1 at 432.100 MHz would not make for a happy radio.

Of course on other bands (not for the contest) the quick 80 meter inverted Vee we stuck up just a year or so back, has deteriorated and is not functional. The big beam on the tower likely has rotten coax, and the rotor shear-pin ist kaput, as it appears to free-wheel in the wind. So no HF antennas are currently available. Next chance I can get someone to meet me out there, we will make a run up the pole, and make-better the pully assembly so that we can easily run up a new 80 m antenna. Possibly a multi-band inverted Vee. We have some good enameled solid copper wire available, just need the time and effort to string it up… I had the old Kenwood HF rig active last year, so it is ready to run. The big power amp has not been checked out yet, so it can wait a bit longer. Antennas first.

Anyway, just a quick update. It has been a quiet winter, hardly any visitors to the 4622 club station. Hopefully things will be picking up this spring.
Thanks /;^)


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