[Elecraft] FW: How far can the KPA1500 amp be from the PS?

[Edward R Cole]

I would agree.  If I invested >$5K in a shiny new piece of ham gear I 
would not risk it to damage from moisture.  Besides, I would want to 
admire it every time I sat down in the shack.

With that being said, I have a lot of equipment remotely located at 
tower top or bottom.  Most of my operating is VHF/UHF/mw where RF 
cable losses can be astronomical.  Everything at 900-MHz and up is 
remote in outside enclosures (usually fiberglass).  NONE are 
air-tight and are open on bottom for free air exchange.  I live in a 
coastal, sub-arctic climate which guarantee's moist air.  Temperature 
changes will pull outside air into sealed compartments which have no 
path to exhaust back outside.  Even if you live in the desert, 
temperature pumping exists (less extremely a air is drier).

I am currently in process of installing a 1000w 6m,1200w 2m, and 600w 
1296 amplifiers at base of their respective antennas (towers).  All 
will have cooling fans with exterior air exchange (typically drawing 
air thru openings in bottom of enclosure and exhausted by fans thru 
separate vents (shielded from water entry).

For HF, cable loss is insignificant if they are rated for QRO; keep 
it inside, warm/cool and dry.

73, Ed

Rick N6XI, writes (edited):

I would advise against putting the amp
outdoors. Even if the housing is 100% water tight forever, Murphy almost
guarantees that the first failure that causes you to want to access the
amplifier will occur during a downpour or snow storm.


73, Ed - KL7UW
   http://www.kl7uw.com
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