Saturday, April 22, 2017

VFO Tribal Design Wisdom from Joseph Carr K4IPV (SK)

I had in my files somewhere this great article by Joseph Carr K4IPV about the design of ham band VFOs, but then I lost it.  Yesterday I found it, but the paper copy was in bad shape.  Internet to the rescue!  Here it is.  Go to page 79.  
http://www.americanradiohistory.com/Archive-Poptronics/90s/93/PE-1993-07.pdf

There is a follow-up article the following month, on page 78:
http://www.americanradiohistory.com/Archive-Poptronics/90s/93/PE-1993-08.pdf

Something I heard on 75 meter AM this morning may have gotten me thinking about VFOs: I hear that International Crystals is going out of business.  That might be the last manufacturer willing to make bespoke crystals.   If that is true, that has big implications for homebrewers.   We will now have to build stable VFOs or succumb to the siren song of the digi synthesizers.  "L and C FOREVER!"

Joe Carr K4IPV mad so many contributions to the radio art.   I have several of his books.  He had a real talent for explaining circuits.  Sadly, I find very little information about him on the internet.  I know he lived in the same Virginia town that I live in.  Does anyone know anything else about Joe Carr? 
http://forums.qrz.com/index.php?threads/joseph-carr-ki4pv-silent-key.50027/

1 comment:

  1. I recently bought crystals from International. must have been among their last customers. These very fine crystals cost my boss $46 a piece. Digikey has programmable oscillators from 1 to 125 MHz for $4.10 inclusive of programming. Perhaps it's just time to move on.
    Chip KM4SJN

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