[ARC5] "Curing Chirp in Command Transmitters" T-53 Self Heating / Manuals

[Kenneth G. Gordon]

On 6 Oct 2014 at 13:01, Mike Morrow wrote:

> > I wondered about that heating effect, too.
> 
> The total resistance of the windings of T-53A and T-53B through which
> the filament current for the 1626 flows is, at most, 0.3 ohms.  If the
> rated 1626 filament current of 0.25 amps is flowing in those windings,
> a **very negligible** 22 milliwatts is generated against the very
> substantial mass of T-53's open ceramic coil form.  Self-heating of T-53
> is non-substantive.

Neither of my two questions have yet been answered. Therefore, I will repeat 
them here and add a third:

1) What effect is there on operation of the 1626 VFO if T-53A/B is NOT 
used?

2) Does the fact that filament current flows through the cathode tap of the 
oscillator coil cause localized heating which thereby contributes to drift?

(I would imagine that if there WAS localized heating, this would 
CONTRIBUTE to stability in the VFO in their original use at altitude and the 
accompanying low temperatures, but for OUR uses, that would have the 
opposite effect.)

3) Does applying AC to T-53 induce 60 Hz modulation into the VFO's output?

(Following unnecessary and perjorative crap deleted).

> That itself is NOT an informed attitude.  Frankly, I am certain that you

Frankly, in my "uninformed opinion", the main, and possibly sole, cause of 
chrip in commmand transmitters is wimpy power supplies...

Ken W7EKB