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Re: L band survey : Thanks!

To all who replied to my request for what you are using for L band uplink:
my sincere thanks! Unfortunately, I seem to be running in too many
directions at once lately and my manners have slipped so I didn't thank
each of you individually. I got some really good info and will use it in my
Dayton talk.

In response to several questions: I use a variety of L band uplink
arrangements. A homebrew transmit converter (500 mW output, widely
variable; recently modified to cure some rather awful FMing) drives a
1-1/2W brick, which drives an M57762 brick (~10W) that sometimes is mounted
up on the tower behind the antenna and sometimes lives in the shack driving
another amp. The final amp is a homebrew firebottle amp.... a pair of
7289's in a sliding drawer cavity. While it is easily capable of >150W, I
just run it at a comfortable level to insure I am below the beacon. I use a
tower-mounted transfer relay to switch between a 15 turn helix (the one in
my ARRL Handbook article, with a housebrick as a counterweight when the
brick amp isn't up there) and a 55 el loop yagi. Makes for some interesting
comparisons, though I never put the time into quantifying their relative
merit versus pointing angles like I should have. Which is why I asked the
question. My own experience is in line with your responses; the 10W with
the 15T helix is satisfactory for SSB at good pointing angles (<15 degrees)
and CW way beyond that (why don't we use CW more?), but overall a little
light for easy conversation.

73 and Thanks! (and see you at Dayton!)

Ed Krome K9EK
editor/author  "Mode S: The Book" among other things

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