Re: OT: The Colpitts mystery
Posted by
Vic Rosenthal on
Apr 27, 2020; 7:00pm
URL: http://elecraft.85.s1.nabble.com/Voltage-drop-in-DX-Power-to-K3-tp7660188p7660254.html
Mine was the push-pull triode RF amplifier (not "linear"!), making sure
to show the neutralization circuit. They didn't want any high-powered
self-excited oscillators on the bands!
73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
CWops no. 5
http://www.qsl.net/k2vco/On 27/04/2020 21:03, Fred Jensen wrote:
> What was it with the FCC and the Colpitts oscillator schematic on the
> exams in the 50's/early 60's? It was on my General ['54] and Extra
> ['56] exams, and practically everyone else I've asked says it was on
> theirs too. There are other oscillator circuits of the day. Colpitts
> uses capacitive feedback which is somewhat more stable than a Hartley
> with its "Tickler Coil," but the FCC seemed fixated on the Colpitts for
> some reason. The schematic and operation of a dual-triode 1-shot was
> also popular.
>
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
>
> On 4/26/2020 7:28 PM, N4ZR wrote:
>> As for the licensing tests, did you have to draw a Colpitts
>> oscillator? IIRC, that was on my General exam in 1955.
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