[ARC5] "Curing Chirp in Command Transmitters" MO T-53, Vibration, AC Heater Power

[Brian]

Hello Mike,

Sounds like Sarnoff's ripping off others' ideas again. Dr Drake's design 
preceded the RCA patent by many years.

BTW, Sarnoff also wrecked the life of Major Edwin Armstrong over patents for 
the superheterodyne principle and frequency modulation.

73 e Brian, VK2GCE.

On Tuesday, October 07, 2014 6:07 AM , you said:

Ken, I hope you won't mind my reply below being made to the list.

Ken wrote:

> I have two questions concerning T-53B:
>
> 1) what, exactly, is the EFFECT on the VFO stability when T-53B is NOT
> used, and...

The circuit is designed to eliminate **vibration-induced MO frequency 
changes**.

US patent 2,189,402 (applied for June 1938) was granted to RCA on February 
6,
1940 for an oscillator circuit that is functionally similar to the one used
in the "command set" transmitters.  See

  http://pdfpiw.uspto.gov/.piw?docid=02189402&SectionNum=1
  http://pdfpiw.uspto.gov/.piw?docid=02189402&SectionNum=2

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