I acquired a (large) used rooftop log periodic broadcast reception antenna and it didn't come with wiring. I figure I could use it for parts if nothing else but first I'd like to see if this thing actually works for receiving distant stations.
From passing from amateur knowledge, these log periodic antennas need to be matched to the impedance of coaxial cable, nevermind the balanced nature to the unbalanced nature of co-ax. So I'll need to locate a balun.
So I was wondering about people who worked on rooftop terrestrial broadcast antennas...are these log periodic "dipole" typically 300Ω and I'll need to get a 4:1 balun to attach to 75Ω co-ax? Should I feed twin lead 300Ω down to the house and have the balun inside the house or is it just like transmitting antennas where it's best to have these matching networks close to the feed point?
I just so happen to have a 4:1 300Ω to 75Ω balun but it's not sealed for outdoor use, so would be best to keep it indoors or perhaps take it in when it rains...
From passing from amateur knowledge, these log periodic antennas need to be matched to the impedance of coaxial cable, nevermind the balanced nature to the unbalanced nature of co-ax. So I'll need to locate a balun.
So I was wondering about people who worked on rooftop terrestrial broadcast antennas...are these log periodic "dipole" typically 300Ω and I'll need to get a 4:1 balun to attach to 75Ω co-ax? Should I feed twin lead 300Ω down to the house and have the balun inside the house or is it just like transmitting antennas where it's best to have these matching networks close to the feed point?
I just so happen to have a 4:1 300Ω to 75Ω balun but it's not sealed for outdoor use, so would be best to keep it indoors or perhaps take it in when it rains...
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