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RobertMacy RobertMacy is offline
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Default "Random" Circuit Needed.

On Wed, 01 Apr 2015 12:14:13 -0700, Jim Thompson

On Wed, 01 Apr 2015 15:07:54 -0400, Phil Hobbs

How random? You could use a 16-bit PRBS made from two HC299 and an
HC86. Feed back Q14 XOR Q13, and tap out four stages to a HC154 demux.
If you need better randomness, use four PRBSes of different length.


Phil Hobbs

I just need semi-random enough to test a fast AGC.

...Jim Thompson

Uniform distribution sounds like a great 'first' test.

However, often modulators are not always set up to 'scramble' the data to
create uniform distribution. Does that mean you should also check some
weird distributions reflecting fixed/sloppy modulation? Especially if the
16 level space has any type of one to one relationship, like text, mime
format, or images which have repeating patterns [don't they?]

Anyway, just to be sure, you may want to try some weird distributions just
to make certain the AGC doesn't respond to these 'patterns'.