[ARC5] "Curing Chirp in Command Transmitters"

[WA5CAB--- via ARC5]

Glen,

I'm sorry, but your statement isn't technically correct.  Someone yesterday 
or the day before (I'm sorry but I didn't pay any attention to who posted 
it) already explained this.  Go back and read it. Plus the cathode bias on 
the 1629 will be screwed up and modulated at 60 CPS.

In a message dated 10/5/2014 6:20:36 PM Central Daylight Time, 
arc5 at mailman.qth.net writes: 
> Whether or not the heaters run from AC or DC doesn't really matter.  The 
> tubes have indirectly heated cathodes which are independent of the heater 
> voltage source.
> 
> Glen, K9STH 
> 
> Website:  http://k9sth.net
> 
> 
> On Sunday, October 5, 2014 6:13 PM, AKLDGUY . <neilb0627 at gmail.com> wrote:
> 
> 
> 
> >The justification is that airplanes of that time had DC power @24/28V!
> 
> Well gee, I knew that back in 1965 when I first started playing with
> Command sets.
> Yes, 1965. Maybe before you were born, lol.
> 
> Lately I've come to question the need to modify the VFO wiring when
> using AC for
> the heaters.
> 
> The typical mod back then was to disconnect the 1626's heater pins from 
> the
> VFO
> circuitry and connect them directly to heater line and ground.
> 
> On re-appraising the circuit recently, I think there's no justification 
> for
> doing that.
> 
> 73 de Neil ZL1ANM
> 
> On Mon, Oct 6, 2014 at 11:56 AM, Francesco Ledda <frledda at att.net> wrote:
> 
> >The justification is that airplanes of that time had DC power @24/28V!
> >
> >Sent from my iPhone
> >
> >>On Oct 5, 2014, at 17:49, "AKLDGUY ." <neilb0627 at gmail.com> wrote:
> >>
> >>Yes but what is the technical justification?
> >>
> >>73 de Neil ZL1ANM
> >>
> >>On Mon, Oct 6, 2014 at 11:26 AM, Kenneth G. Gordon <
> >kgordon2006 at frontier.com
> >>>wrote:
> >>
> >>>>On 6 Oct 2014 at 11:17, AKLDGUY . wrote:
> >>>>
> >>>>I can't think of a good reason to run the heaters on DC.
> >>>>Can anyone suggest one?
> >>>
> >>>Yes. Because the transmitters (and receivers) were designed for DC, not
> >AC.
> >>>
> >>>Ken W7EKB
> >>>_______________________________________

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