Hi. I have a transmitter 500w. I was operating my transmitter with low SWR
(250w FWD power and 0,5w RFL power). The antenna's match system is only a
series variable capacitor 0-500pf. With this variable capacitor i can achieve
very low SWR.
My antenna (the feed point i mean) was starting inside the transmitter's metal
house, and i have some problems with my pll's lock and the modulation. So i
decide to move the antenna's feedpoint out of transmitter's metal house. To
achieve this i used about 2 meters of coaxial cable RG214 between the variable
capacitor and the antenna's feed point. After this change i have very high SWR
!. With 25w FWD power output, i have 1w RFL power! What do you think is the
problem? The 2 meters RG214? I am thinking that these 2 meters of RG214 cable
are putting paraller capacitance between the feed point and the ground system.
How can i zero this capacitance? If i put a varable coil in paraller with the
RG214? Or it is wrong to use RG214 between variable capacitor and antenna's
feed point and i must use RG214 only between transmitter and variable capacitor?
thank you
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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