The Bliley VF-1
I was reading about the death of Ross Hull, the editor of QST, in the November 1938 issue of QST.
https://archive.org/details/QST_1938_11
Then I browsed through the rest of that issue and came upon an ad for the Bliley VF-1, variable crystal.
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| I'd never heard of this before |
Wow, what a neat idea although I can see why other crystal companies never got into the act. Selling someone one crystal versus a handful probably wasn't considered a good business decision.
Doing a little internet searching came up with a boatload of info, especially this page.
http://www.bliley.net/XTAL/Variables.html
The frequency was varied by mechanically distorting the specially ground crystal. There are patents, promo info and other ads on the internet. Also there was a VF-2 and patents for a variable crystal that would have covered 200 kHz of 40 meters, take that super VXO !
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| theVF-1 patent drawing 2079540 |
Plugging $7.50 into the BLS calculator: https://data.bls.gov/cgi-bin/cpicalc.pl?cost1=7.50&year1=193811&year2=202203 results in a price of over $150
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| $7.50 was a fair bit of money in 1938 |
So naturally I did some searching on ebay as well and yikes,
expensive ! And as you might imagine, the coverage of the VF-1 units
for sale isn't always amenable to the modern usage of the bands.
Still, what a neat idea.
Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm