Having previously used parts of my 6cm eme system for portable DATV operation from Titterstone Clee, Brown Clee and Cleeve common it was very apparent that the large numbers of interconnecting cables and its lack of waterproofness was a handicap. A dedicated, waterproof system was needed , in the style of the 24 GHz system.
Having not used the Fujitsu amp in the 6cm FMTV system I had an amplifier. I also had a DB6NT preamplifier, however I needed a compact Transverter. The DB6NT mk4 had good performance but cost a lot. I looked around for a second hand one to no avail. In a conversation with G4DDK at Heathrow airport on our way to Frederichshaven we were discussing what we were looking for. He was toying with the idea of a 6cm DB6NT mk4 xverter to upgrade the mk2 in his eme system. I offered to buy his mk2 and this convinced him to go ahead with the plan. Problem solved
Sam shipped the transverter which produced over 200mW (too much for the Fujitsu amp) and could hear the GB3OHM beacon on a patch antenna, time for encapsulation.
I found another waterproof box like the one used on 24 GHz in which the Fujitsu amp just fitted. The Transverter was mounted on a plate on the sidewall of the box, the amplifier was mounted in the base of the box.
To offer some protection and to allow monitoring when masthead mounted a PIC controller was deployed. It monitors positive and negative volts, current and temperature. It also sequences the antenna change over relay and bias control
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