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Phil Allison[_2_] Phil Allison[_2_] is offline
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Default Why would an FM signal amplifier make some signals disappear?


"Jeff Liebermann Radio Ham ****wit "

One guess(tm) is that the Radio Shock amplifier is rather noisy. The
additional noise generated by the amplifier is stronger than the
previously weak signals. If really awful, weak signals will be
totally lost in the noise.


** ********.


The Radio Shock amplifier might be oscillating, thus creating the
in-band strong signal necessary to create the blocking effect.


** More ********.

Results would be very bad all over the band.


The FM tuner might have an AGC section. This is required for direct
digital receivers that have an A/D converter in the front end of at
the IF frequency. The AGC is necessary to use the entire range of the
A/D. These usually have a limited dynamic (amplitude) range and are
easily overloaded. When amplified, this would cause a strong signal
to disappear as it runs out of head room.


** Massive pile of ******** !!!

FM signals are not affected by amplitude limiting - cos limiting is just
what the IF stage is designed to do.

****WIT !!!




..... Phil