Nov 12-13 was the ARRL EME contest. In contrast to the last year, the moon was visible, the weather was excellent, and I had a 1 KW Beko amp. I could make many QSOs.
My EME system is set up outside as I do a manual positioning.
I turned the radio on and the signals were strong. But the amp was turning itself off because of too high SWR. It was working at 200W but this is too little in EME.
I looked at my fixture that combines the two 9 element 2m beams (2M9X by M2) into a single cable. It consisted of 2 x 3/2 wave RG6 cable with F connectors, with the ends soldered and connected with a clamp to a LMR400 type cable.
That arrangement was supposed to last a month but lasted half a year until it broke at the worst possible time. I tried to fix it but at 11 PM at night it was hard.
A few days later I terminated the cable with the PL259 to F adapter and checked the impedances for each antenna separately. They were around 110 Ohm. After combining the two antennas with a UHF splitter, SWR was 1.6. It turned out that the connector had too much capacitance.
So I used a bar with several UHF connectors from a junk box. Now SWR is 1.1! How long will the connectors last?
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