On a sunny day (18 Aug 2006 16:51:43 -0700) it happened "SparkySKO"
wrote in
om:

AFAIK, an Automatic Noise Limiter is just a diode that shunts off
spikes (zener diode?). Can anyone help shed any light on my quest to
homebrew one? (Like what they might use, or where it might go).

I couldn't find any examples of one or schematics of one, so I'm at a
loss.


One type of ANL in analog TV used a capacitance diode.
Anytime a big spike occurred, it de-tuned the circuit (38MHz IF).
This was Philips design IIRC, possibly patented.

If you wanted to go more 'advanced' you could delay the signal
with an analog delay line for a few micro seconds, trigger some
circuit on the spike, and then mute the delayed the signal _before_
the spike starts for some time...

Could be done digital too(when will CB go digital to 300 channels
in the same band? oh well...)

If you want to use the varicap system all you need is a varicap, capacitor,
resistor bias likely.