[time-nuts] Are there SC-crystals out there in the wild that are not Overtone?

[jimlux]

On 2/27/20 8:45 AM, Richard (Rick) Karlquist wrote:
> OTOH, you could build a simple Colpitts
> oscillator and see where it oscillates.
> That's what they did back in the dark
> ages.
> 
> Any time nut should be up for that.
> 
> Rick N6RK
> 

But does a deForest Audion (ref Colpitts patent 1624537 1918) have 
enough gain at 5 or 10 MHz?

I guess so, by 1930 deForest was selling oscillators and receivers at 
15,000 kilocycles. Although I didn't see any indication of crystal 
oscillators - they're all LC tuned. (One mention of crystal control is 
in an article about a SW crystal controlled Transmitter by Lester 
Spangenberg)

https://www.americanradiohistory.com/Archive-Radio-News/30s/Radio-News-1930-05-R.pdf

(Timenuts - your experience and training probably qualifies you for a 
job in Radio-Television - Talking Pictures, see the ads!)

I seem to recall that crystals for frequency control (on a commercial 
basis) were sort of a post WW2 thing (partly because of developments in 
piezo hydrophones for sonar)