On 9/25/16 5:53 PM, Guy Olinger wrote:
The 1.5 kW PEP is at the amplifier output.
That has been clarified with the FCC multiple times. Tuner, feedline,
antenna system losses are your problem. You are diminished by those
losses unless you either have no losses, or run illegally.
Interesting, can you point to an opinion letter or enforcement action
that says this?
The commercial measurement scheme does not apply to the amateur service
except for a couple bands where that particular band references
effective radiated power. 1.5 kW is not allowed on those amateur bands.
73, Guy K2AV.
On Sun, Sep 25, 2016 at 7:07 PM, jimlux <jimlux@earthlink.net
<mailto:jimlux@earthlink.net>> wrote:
On 9/25/16 12:05 PM, Guy Olinger wrote:
On Sun, Sep 25, 2016 at 12:25 PM, Jim Brown
<jim@audiosystemsgroup.com <mailto:jim@audiosystemsgroup.com>>
wrote:
On Sun,9/25/2016 6:49 AM, Steve London wrote:
What problem(s) are we attempting to solve with chokes on
the 4-square
feedlines ?
Noise.
Noise, yes. Gotta give you that one, but the main reason for the
4 square
was TX gain, right? You do have listening antennas for 160 and
80? So we
have to worry about *loss*. Loss eats up gain from patterns.
Loss eats up
amplifier output. Your *system* gain past your transceiver is
antenna gain
+ amplifier gain *** minus LOSSES ***.
Diversion of power to miscellaneous conductor paths is almost
universally
lossy and never in directions and modes desired in our attempts at
directional arrays.
So measure your output power at the system interface to the
"antenna".. put 1500 watts (total) into your 4 antennas: sum the
powers at each element (including if you have phased them so you
have a negative element). That's what commercial broadcasters do,
isn't it?
The regulations don't say "amplifier output", they say
"PEP (peak envelope power). The average power supplied to the antenna
transmission line by a transmitter during one RF cycle at the crest of
the modulation envelope taken under normal operating conditions. "
"(b) No station may transmit with a transmitter power exceeding 1.5
kW PEP. "
If I define my "antenna transmission line" reference plane at the
antenna feed points, I think that works.
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