A Tale of a Tall Tower
Part 2: Getting it together
 ur first episode last month found us doing a quick test of the W7LT 160 meter antenna, a 300 foot tall vertical, after building a matching network. That Friday evening the group gathered at the site to assemble the station for our first contest. With K7RUN leading, N7RX, KC7PXF, KD7INU, and W7PR got Neal's IC-765 transceiver and a TL-922A amplifier in place. We ran 220 volts AC to the amp, and feedline to the remotely-controlled antenna switch in the basement. At 2200 hours we watched the power output drop to zero on the AM broad-cast transmitter as it left the air for the night.
 K7RUN adjusting the matching network at the base of the tower, prior to the first efforts at using it on 160 meters.
We gathered up the new network along with John's test gear and went to the base of the tower. The network was installed, and while John was tuning it for a good match, we raised a rain fly over the now open cabinet housing the two networks. Standing in the light drizzle under the massive base insulated tower, we were all wait-ing in anticipation of getting on the air. The contest had started hours earlier in the day. After several adjustments and then connecting the coax at the switch, we did some on the air checks. John declared it "matched" to the station, some 200 feet away over the 2.25 inch Heliax feedline.
We returned to the new "shack" to find Neal tuning around to see what the contest activity was like. West Coast stations were heard and we began working all we could hear, after tuning up the 1200 watt amp, with no trouble. We began to realize the band was not in good shape, and we had to really listen hard for new stations to call or answering our CQs. The contest was CQ SSB World Wide DX (incorrectly reported last month as the ARRL Sweepstakes, my error) and there should have been foreign stations on the air wanting to work the US. But it was not to be, with high noise levels the problem.
As 0600 approached we shut down and disconnected our network, put the normal jumpers back in and watched as the 10,000 watt transmitter came back on for the day. We went home and rested up, ready to come back and reactivate W7LT again Saturday night. Things were easier to get up and running that night, and we again encountered the noisy band conditions that plagued stations trying to make contacts. Being near the peak of the sunspot cycle meant that the low bands like 160, 80 and 40 meters were actually worse than normal. But we stuck with it and made as many contacts as we could.
At about 0500 we heard a very weak station responding to our
CQs. After several "agains", we copied all of the exchange. It was VK6HD. W7LT had been heard in Australia! This development brought smiles and cheers by the remaining diehards in the group. As I later learned after an e-mail exchange, Mike had heard only W7LT and one New Zealand station that morning during the contest. And we were "10 to 20 dB over S9 very strong". As he learned of our 5/8 wave vertical, his reply was "Your tower is working!" As we wearily tore down the 160 station we began to plan our next attempt, and what we might do to improve it. More next time.
-W7PR
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