OK I'm sorry, I see I asked a very short question with very little background.
I'd be very happy to accept the answer of can't happen, don't give it a second thought.
But in the example I gave above the 23 dBi number was not chosen arbitrarily just to test GroundUrMast's numbers.
I have/am designing a true 23-24 dBi home brew E-Z build parabola (96 sq. feet) with slightly higher gain than the horizontal stack of two 8 foot parabolas seen here.
http://www.wade-antenna.com/Wade/uhfparabolic.pdf
I can show you the nec models.
and this is my plot/report I did round -15.9 to -16 dBm
http://www.tvfool.com/?option=com_wr...3e476ecbd7806e
I will be building a full scale prototype to take modeling measurements, and of course to play with.
I wouldn't be using it to provide local channels, just a test/DX-toy but it could get accidentally pointed at the local flamethrower or a very strong reflection of it.
So with signal levels ~8 times what any mass produced antenna produces does this change your opinion?
Because if my math above is not flawed it looks to me like I'm very close to producing a potentially damaging signal level.
If that is the case I may want to try and trade some of the massive gain for more beamwidth at least for my personal one.
My development efforts were kind of paused when I noticed references to needing better than consumer grade down stream equipment to handle the signal levels of the wade.
And if it matters the feed is a log periodic dipole array originally designed for 470-800 MHz. with a native impedance of 75 ohms
So don't mistake my questioning your answers as disrespect.
More a quest for a more complete understanding.
BTW klitz tech says their lowest priced amp (maybe all of them) overloads at -5 dBm and didn't know what signal level damage occurred.(it was the sales dept)
But use of an amp would just switch my concerns to the health of the amp. instead of the tuner.
Is that .7fv the point where damage potential exists or is it some higher (unknown) number based on the actual failure value of the actual diode in question?