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legg legg is offline
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Default Harman Kardon FM100 - early version?

On Tue, 31 Jul 2012 16:30:47 -0500, John Byrns
wrote:

The "rumble filter" circuit in this tuner is sort of interesting. Rather than
inserting a low pass filter in the audio section, it changes the time constant
of the AFC network, when the time constant is lowered more of the "rumble"
frequencies are feedback cutting the low frequency audio response. This means
that the "rumble filter" won't work when the AFC is off. Also the labeling for
the "ON" and "OFF" positions of the "rumble filter" switch appear to be reversed.


Going......going.....

http://www.ebay.com/itm/300757745636...84.m1555.l2649

gone!

RL