At 09:23 AM 11/23/03 -0800, Bob Tellefsen wrote:|
One thing to check.
How rf-tight is the transmitter case?
Run a piece of transmission line from your TV set to the transmitter.
Move the loose end of the transmission line around the transmitter to
see where rf energy leaks out. Once rf is on the outside of your coax
feedline, no low pass filter can do much for you.
While the harmonic is there, it may not necessarily be the cause of the
TVI. some television sets in this country used to have their IF at 21 MHz;
others are subject to fundamental overload interference. Try a high-pass
filter on the input of the television (I assume it is only one set that has
the problem, or are there many? Anyhow, I think this is worth a try before
you go further with exploring why the low-pass doesn't appear to help.
73, Pete N4ZR
The World HF Contest Station Database was updated October 29.
2469 stations are listed -- 29 new and over 100 updated.
Are you current? www.pvrc.org/wcsd/wcsdsearch.htm
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