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Screening can apetrure radiation.

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dr pepper

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Ok I have a FLL transmitter circuit, the VCO works well on its own, however when I place the prescaler for the pic micro near the circuit the digital roar from the 74ac logic screws everything up due to harmonics etc.
I was wondering how big a cutout I could have in my screening can made from single sided PCB I could have.
I was planning on putting all the digital stuff in its own totally screened enclosure, just a cutout for the 2 line display, about 20 by 75mm, just wondered whether this would be an issue at 100MHZ.
 

Thats tighter than I thought, lambda/30 was a figure I seem to recall.
Yup I have 0.1s accross the rails and the power supply pins of the ic's.
The issue is more other equipment on the bench, the roar from the acl logic wipes out my dab radio, I think the square edges from the acl's are rich in harmonics which in turn radiates from the pcb, well 'dead bug' pcb are being radiated.
The pic micro itlsef doesnt create much trouble, must have slower rise times, for that reason I'm thinking of a 'hc (rather than an 'acl) buffer on the output of the presacler and just put the latter in the screening can as only the prescaler gives trouble.
 

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