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Build your own cd4 demodulator scans

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2K Club - QQ Super Nova
QQ Supporter
Mar 30, 2009
London, England
Thanks so much for posting this, excellent stuff and the passage about the High Blend function is fascinating, not least because the Braun demod I picked up recently has a Blend switch on the rear panel so I'll have a fiddle about with that now I know what it does.


500 Club - QQ All-Star
May 28, 2011
NW Ontario
I don't think I've seen this article before, I became an avid reader of Audio about that time (or just after), I'm surprised that I missed it. The blend switch is a good idea, it should reduce a lot of the noise and distortion from those troublesome discs. You could put it in a small utility box inserted at the output of your Demodulator, I would try out different capacitor values as well.