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Jeff Liebermann Jeff Liebermann is offline
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Default Interference in FM radio reception.

On Wed, 11 Jan 2012 09:18:11 -0800, Jeff Liebermann
wrote:

Ummm... you have it somewhat wrong. The hi pass filter goes on the 27
MHz xmitter, in order to remove any spurious rubbish from the transmit
signal at 21.4MHz. A low pass filter would NOT work on the TV set as
the frequency range is 54 to 800MHz and a low pass filter would block
all of it. However, a 21MHz notch filter on the antenna would work
wonders.


Argh. That's all wrong. I somehow merged the 21.4IF feedthru problem
with the CB harmonic filter. The lo-pass filter should be on the CB
xmitter, to reduce the 2nd harmonic that trashed Channel 2. The 54MHz
high pass filter goes on TV, to keep the CB radio from generating
harmonics in the tuner section.

Remind me not to post anything before my morning coffee fix.

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Jeff Liebermann
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