Ron, KU7Y compares DX77 and homemede 24' GP with 40 radials 40' long.
He claims 3S units DX77 advantage on 20/40m and the opposite at 30m of
FT-1000MP. Both antennas are fed with CATV 75 Ohm coax.
Ron claims: On 40 an 20m, 24' pipe is a very poor non resonant antenna
and has lots of loss!
Here on the Old continent we convert feet into meters and find Ron's pipe 7.2m
long which makes it long enough for 20m band and reasonable size for 40m.
Radiation resistance is even on 40m probably 3 times higher than ground
resistance with 40 radials 12m long on Nevada soil.
There is some reactance present on both bands as the antenna is not resonant
but I am sure Ron's tuner within FT-1000MP can match pipe to 50 Ohms nicely!
So I wonder where is all the energy lost apart from >75% efficiency on 40m?
73 de Mario, S56A, N1YU.
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