Topband: Hi Z Four Square/ FCP Commissioning
weeksmgr at hotmail.com
Tue Aug 21 22:17:59 EDT 2012
Over the last several weeks I and some others in WVDXA have been helping our friend Tim K8RRT gear up for the next topband season. First, we commissioned one of K2AV's FCP systems under a 1/4 wave 160 L. Preliminary Reverse Beacon Network signal comparisons between K8RRT's L /FCP and my similar inverted L using elevated radials indicate similar signal reports with both of us running the same power level. More testing is needed, after I do some minor repairs to my system. The band was not open to EU when our tests were run, but we had 5 or 6 NA spotting station reports with which to compare signals. The FCP is obviously working, but the jury is still out as to how closely in varying condx it will compare with a few elevated radials.
Tim had no trouble breaking a good pileup on CY9M for a first Q with the FCP and he has had no problem at all making QSO's with western EU in the last couple of days. We are encouraged by the operational results so far, although I concede they don't prove anything other than the antenna with FCP works.
On Monday Tim and I built a Hi Z Antenna four square array, with assistance last Friday from W8TN in laying out the vertical locations. This is the first one of these systems in use around these parts. We were very careful to accurately measure the array layout and all of the interconnecting cables. At the end of the day, it was with great anticipation and some apprehension that the power switch was turned on for the Hi Z system. Signals poured forth from Tim's K3 on the high end of the AM broadcast band, much to our relief.
Whenever I build a RX antenna, the first tests are always run on the high end of the AM band. The front to back ratio and sensitivity of the Hi Z system was amazing. On just about every AM channel, we could separate several stations simply by rotating the switch. On one frequency, the Hi Z four square produced an S9 signal which could not be detected at all by Tim's 1/4 wave transmit L. Later that night, Tim worked two EU stations on 160 that were not detectable on his transmit antenna. On 80 and 40M, Tim could copy signals that could not be copied and in some cases even detected on the xmit antennas. The first day results made a believer out of me! If my hilltop were not so congested, I would install one of these systems, without hesitation. Unfortunately, the clear space is just not available. Guess I am stuck with short beverages and dual flags on the sides of the hill, same as the last few seasons.
NH8S upcoming on Swains Island will have two of these Hi Z four square arrays for the low bands. I expect they will be able to hear well! WVDXA has two ops on the Swains expedition: W8TN and W8HC. GL in the chase!
73 Charlie N8RR
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