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Old May 27th 07, 01:13 PM posted to rec.radio.amateur.equipment
Lynn Richardson Lynn Richardson is offline
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First recorded activity by RadioBanter: May 2007
Posts: 3
Default AGC curve for FM Rx

Some FM rigs use FM Rx chips that have a signal strength output, Lke the
Signetics NE-605. These can have a dynamic range of more than 80 dB with
excellent liniarity and temperature stability. In fact some DIY spectrum
analyzers use these in the 'video' IF for the level detector.

On Sat, 26 May 2007 14:01:53 -0400, Dave wrote:

I didn't know FM rigs had an AGC curve. FM does not need any AGC.

Once the input signal is strong enough to fully drive the Limiter, typically 10
uV, the magnitude of the input signal is a don't care.

Karl wrote:

I've been working on making a decent chart out of MS-Excel and still
trying to figure out the best "AVERAGE" syntax to use for the Y axis.
I've been browsing around the web, stopped by Tu-Cows.com to see if
they had any templates for excel. Any ideas for making a chart to
plot AGC curves? I have several (background) links on my voting
system and wanted to make some bench marks. At work we do it manually
in pencil, for our microwave RSLs.

Any input from you would be appreciated. It's for Amateur Radio.

Regards,