balun and image
Dear all,
I just noticed tonight that, while listening what seemed to be Bucurest radio on
5900 kHz between 2100 and 2200 UTC, I had a strong image of Vatican Radio. This
Vatican radio transmition was on 5885 kHz, much stronger (closer, I'm in Paris
surburbs, France) than Bucarest. I disconnected my external antenna with balun,
and Vatican radio image disapeared from 5900 freq just listening off the whip.
Then I tried the antenna without the balun : the signal improvement is less than
with the balun, but at least I don't have the image...
The balun is home made, with a ferrite core than comes in two clippable parts
(used to reduce noise on wires) : so it is not a perfect balun for sure, but it
gives good results anyway for me...
I had the same thing occuring with my Sangean 909 and Sony SW100.
Can anyone explain that image phenomena to the humble radio beginner that I am ? :-)
Thanks in advance !!!
Charly
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