[TowerTalk] 4 square for 80

[Guy Olinger]

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.

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 at 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 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.
>
>
>
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