[ARC5] My ARC-5 40 meter station

[Dennis DuVall]

Yes, the ARC-5s were plate and screen modulated but ran low screen  
voltage so didn't get any more power out than the SCR-274N.  Probably  
easier to tune up, though.  Would be interesting to up the screen  
voltage and see just how much undistorted audio one can get out of an  
MD-7.  Very small modulation xformer in the thing.

Dennis DuVall
Glendale, CA

****************

On Feb 22, 2015, at 4:58 AM, Mike Morrow wrote:

>
>
>>> The SCR-274-N and ATA transmitters mentioned in this thread use PA  
>>> screen modulation, not plate, in the military systems.  Only the  
>>> AN/ARC-5 transmitters are plate and screen modulated.
>>> Mike / KK5F
>
>> I didn’t know that. What modulator do they use? The only mod unit  
>> I’m familiar
>> with is the MD-7 and it is plate/screen.
>
> Refer to the article at
> http://en.wikipedia.org/w/index.php?title=AN/ARC-5
> for a concise presetation of these three command sets and their  
> differing components.
>
> The modulators are
> ATA:  CBY-50083 or CCT-50083.  Screen mod./one 1625
> SCR-274-N:  BC-456-A, B, or E.  Same as ATA except sidetone AF Z.
> AN/ARC-5:  MD-7/ARC-5.  Plate and screen mod./two 1625
>
> The differences may be studied in detail by referring to the manual  
> copies at the links cited at the bottom of the above wiki article.
>
> Mike / KK5F