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Spots per uW band today:
UK spotter or spotted only.

Solar data:
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Date:21/11/17 Time:11:42
Temp:13C
Wind Speed:10mph
Wind Dir:202deg
Pressure:1002.78mB
Humidity:118%
Dew Point:16.6C
UKHASnet
500W+ 1296MHZ Amp Project

The latest amplifier is much more capable, it is based on the boards that are available from Jim W6PQL and capable of delivering about 600W!

I bought the boards and high power splitter/combiner in late 2009 with intentions of getting it up and running rather quickly but it did not progress until late 2011, just about complete now in July 2012.

Currently i have tested it briefly to around 500W with an external coupler but the meter is not accurate enough to say precicely, DC input current is ~37A @27v on max output so seems to tally up. I have not used expensive ATC capacitors for the output of each amp stage (only Farnell uWave ones rated at 200v) nor the trimmers so this is probably why i have a little less than what maybe possible...

I did not like the idea of snowflaking and tweaking the amp in close proximity at 500W!! so quite happy with the output power as-is, no need for any adjustment, I just put the lid on and installed it near the tropo antennas & dish.

The previous DG0VE 60W amplifier is used to drive the big amp as i only have max 2W available at the end of the coax at the mast where the amplifier will be located.

The controller/Sequencer is The ultimate Amplifier Control Board by W6PQL.

The home made directional coupler made from 0.25" copper coax works fairly well, i had to enclose the coupled port ends in the tin box to stop RF pickup from the output combiner due to proximity.

The output N socket is fairly good quality but had to be bodged to accept the different size coax.. it has held up OK so far!


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