Re: Follow-up Antuino question
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Tom
You got it!? analog VFOs used to drift all over the band.? Then came the Vackar design? which was very stable.? Next seems to have been H&P which made even a? Vackar design? better (cheaper components and less stringent builds) stabilized by H&P).? With PIC? and AVR/Arduino?came really good and inexpensive FLL designs.? PLLs were always? available, but seen by many as too complex and expensive (not really true but still hard? to dispel?the myth, mystique, hype, and traditions).
H&P was seen as an easy and quick fix for old equipment with drifty VFOs.
Arv _._
On Sun, Nov 15, 2020 at 5:24 PM Tom, wb6b < wb6b@...> wrote: On Sun, Nov 15, 2020 at 03:57 PM, Arv Evans wrote:
It tries to hover around one particular frequency.?
So in following the part of this thread that is strictly related to Huff and Puff, was the original reason for the Huff and Puff circuit to create a manual VFO that would jump and hold in accurate increments rather than be free to drift around uniformly. A way to allow operators to dial up drift-free discrete frequencies before digital frequency synthesizers became the primary way to set the frequency of a radio?
The non-drifting VFO settings were more the goal than the actual circuit details of Huff and Puff, itself. Huff and Puff was likely chosen because it was easily implemented with a simple type-d flip-flop, in the pre microprocessors everywhere days?
Tom, wb6b
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