I wanted to do SO2R contesting. My Expert 1.3k can do sort of SO2R but with a substitute antenna like a vertical. So I purchased PG XL, a SO2R amplifier designed for SO2R. I expected an amplifier that would generate 2 KW when pressed hard, and according to newer reviews, would be reasonable quiet. The ARRL review indicated that the amp can run 1.5KW with about 40-50W input. The amp does not have a tuner but can be interfaced with a SO2R tuner called TG XL. SO2R needs an antenna switch, and there is a corresponding one called the Antenna Genius (AG). What is interesting is that all the 4 components: 6600, PG XL, TG XL and AG can be connected via the Ethernet cables, without any other control cables. Simple!
I tried my luck with PG XL in the WAE CW contests as my Expert 1.3k could do only 1200W. But PG XL would not do more than 1200 with 50W input, and when transmitting for a few minutes, it was as as loud as a vacuum cleaner. Brrr. It turned out that with new updates to the amp, perhaps to reduce failures of LDMOS, up to 70W drive is needed for 1.5KW. The amp does not do any more as alarms called APC are activated. Also the amp has a special feature called Meffa to adjust the power supply voltage for each power level, to maximize efficiency; the feature did not seem to work too well.
I connected the AG and it worked really well. Then the tuner. Tuning is easy: press the tune button, then the amp is turned off, the tuner tunes at low power, and the amp is turned on. Different antennas can be pretuned at different frequency segments, and tuning can be turned off for frequency ranges or when SWR is below a prescribed amount.
My tuner seemed to work but on 160m when the antenna is nearly resonant, tuning seemed to make the match worse. So the SWR meter is off. On 10m, tuning increased SWR from 1.2 to 2.1. The tuner is going for service.
To reduce noise, I put the amp with a tuner below the desk. In the future, I will enclose the amp in a box glued with a noise deadening material. In a distant future, the amp can be moved to a separate room or building since the only connections needed are 2 coax cables + an Ethernet cable.
From bottom to top below the table: the amp, the tuner and a dummy load.
On the left wall, a 40m high power filter by VA6AM, the antenna switch and a triplexer by VA6AM.
Over the left side of 6600, two low power passband filters by DXE.
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