On 9/9/20 8:45 PM, Richard (Rick) Karlquist wrote:
On 9/9/2020 8:19 PM, jimlux wrote:
But other than hams, who would that be? The state department uses
stainless steel cable folded terminated dipoles and amps that put out
1kW from 1mW drive.
AFAIK, those antennas are intentionally lossy so they "match" the
transmitter over a broad range of frequencies, along the lines
of the infamous MAXCOM dummy load/antenna.
Rick N6RK
Exactly - the termination dissipates a bunch of power, but so does the wire.
I suggested to someone who was involved in system design for this kind
of thing - you know, a 6dB pad and a random dipole would work just as well..
He said - sure - but we've got these in the catalog, and can you imagine
making a small, light weight, 6dB pad that can dissipate 750W without
glowing?
The SS is something they like from a mechanical standpoint - it doesn't
break, it doesn't corrode, etc. You can store it for 40 years, pull it
out, and it works as well (or as poorly) as new (!).
With ALE, they're making good use of the "if there's a ionospheric path
that supports the link, then EIRP isn't super important - you either got
a path or you don't" They're not in the business of breaking pileups or
digging out the faint DX, after all.
I covet one of those Harris SSPAs..
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