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Author Topic: Par end fed EF-SWL antenna  (Read 279 times)

Offline IZS4

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Par end fed EF-SWL antenna
« on: May 03, 2019, 1816 UTC »
Anyone ever use a Par end fed SWL antenna with a portable such as a Tecsun, Sangean etc? The length is 45'. Doesn't seem like it would overload too bad.

Online Ray Lalleu

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Re: Par end fed EF-SWL antenna
« Reply #1 on: May 03, 2019, 2310 UTC »
Don't use such an antenna with the compact SW receivers :
their antenna input is already high impedance.
Just used any length of wire that  is NOT resonant at any frequency you want to listen to.
edit : with the simple wire end to the antenna input of the receiver, 'resonant' means a quarter wavelength (or an odd multiple). In practice, just use a random length !

I feel that the problem is the line. For good results, take a roll of bifilar wire
(sold as 'HIFI speaker wire' nowadays), tear apart the two wires for a few meters, do a knot to stop the tearing apart, and use the remaining part as a transmission downline to your receiver. The two wires made apart are a doublet that should be drawn horizontally and at right angle with the feedline to get the least noise. The total length of the original roll should not be a resonant length an odd multiple of a quater of a wavelength for any frequency of interest.
« Last Edit: May 03, 2019, 2349 UTC by Ray Lalleu »
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Offline IZS4

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Re: Par end fed EF-SWL antenna
« Reply #2 on: May 06, 2019, 1940 UTC »
Thank you for your response.

Offline pinto vortando

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Re: Par end fed EF-SWL antenna
« Reply #3 on: May 06, 2019, 2147 UTC »
Have successfully used the PAR inductively coupled via a loopstick to various portables for LW and MW work.
For SW, the built in whip antenna or 10" to 20' of wire connected to the antenna jack (if available) generally
will work fine.
Das Radiobunker somewhere in Michigan