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Old January 18th 11, 10:05 PM posted to rec.radio.shortwave
bpnjensen bpnjensen is offline
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Default Five Basic Steps to Better Shortwave Radio Listening [SWL]

On Jan 18, 10:57*am, John Smith wrote:
On 1/18/2011 10:44 AM, bpnjensen wrote:

...
Actually, no, and I am sorry if there was a misunderstanding - I meant
an inline (in the coax) RFI reduction system.


Baluns/ununs really are NOT an RFI reduction system. *They provide
proper impedance matching between antenna and feedline. *Coax, with an
rf choke (can be a balun/unun) allows the feedline to run though noisy
areas and not pick up the noise there, such as when it enters a house
with noise present.

Baluns/ununs/rf-transformers, because of the use in gaining a superior
match (transfer of signal energy) improves signal to noise ratio, in
most instances, and this can appear to be functioning as a "RFI
reduction system."

Some useful links:http://users.belgacom.net/hamradio/s...alun/balun.htm

Regards,
JS


OK, understood, but I have always thought (based on what I have read)
that one of these matching transformers, properly deisgned and
grounded, can bleed off some noise to ground. Am I misled?