[600MRG] EIRP

[Eric NO3M]

An additional reference from FCC: 
https://apps.fcc.gov/eas/comments/GetPublishedDocument.html?id=204&tn=255011

WRC-2012 and most countries are defining 630M power limits in terms of 
EIRP, and most likely, also the FCC when they get around to it. However, 
many experimenters in the US refer to their power in terms of ERP.  
Therefore, what is claimed as 5W ERP is 8.2W EIRP.

ERP = EIRP / 1.64
EIRP = ERP * 1.64

(per definition, ideal dipole [free-space?] has 2.15 dBi gain over 
isotropic radiator, or 1.64 numerical gain).

So, if you are running 5W ERP, cut it back to 3W ERP to get 5W EIRP.

This all begs the question..... does anyone really know what power 
they're running other than what's coming out of the final amplifier 
stage?!?  I'm sure most of pretty darn close though.

73 Eric NO3M / WG2XJM

On 01/27/2015 01:24 PM, Rudy Severns wrote:
> Ed raised a question on my calculation of EIRP to Pr, radiated power.
> According to Fritz's note on the standard definitions ERP is defined with a
> different reference from EIRP!  ERP is referenced to a "dipole" in free
> space while EIRP is referenced to an "isotropic" radiator.  I find that
> distinction bizarre but from Fritz's note that appears to be what the FCC
> has done.  Neil's (XSV) posting last week on this subject has not only the
> calculations but Fritz's original note.  If you think Fritz's interpretation
> is wrong now would be great time to sort it out.  A couple of weeks ago I
> misinterpreted it, using an elaborate explanation, and bought us an extra 3
> dB.  It was very disappointing to lose that.
>
>   
>
> 73, Rudy
>
>