[TowerTalk] 4 square for 80

[jimlux]

On 9/25/16 12:05 PM, Guy Olinger wrote:
> On Sun, Sep 25, 2016 at 12:25 PM, Jim Brown <jim at 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.