[Milsurplus] ART-13

[WA5CAB at cs.com]

Mike,

Well, you're right (of course).  The best photos that I have are of the T-47A 
modified to install the CDA-T out of the CDA-T documentation (8 x 10 
glossies) and I never paid much attention to the other photos showing the switch.  The 
switch is shown on the overall schematic of the AN/ART-13B in the later 
revistions to AN 16-30ART13-4 as S-117, and it's on the simplified schematic of the 
multiplier.  After going and explicitly looking for it, I found the one page 
Parts List for the T-412 showing the switch and capacitor.  S-117 is described 
as "1670 Kc. crystal selector switch".

The T-412/ART-13B front view photo in the manual is apparently of a T-47A 
modified to T-412 (it has jack covers).  I haven't come across any photos showing 
T-47 or COL-52286 so modified, but the CDA-T modification instructions cover 
them and that would appear to be what Rick has.  So as I've already told him, 
the added switch is "official", but without the label which is visible in the 
photo in the manual.

In a message dated 3/5/2006 5:37:43 PM Central Standard Time, 
AAF-Radio-1 at cox.net writes: 
> I guess I've never seen an ART-13B /without/ that switch.  I've had a 
> half dozen here at one time or another with the CDA-T, all with the 
> switch, and all with a nameplate to the right of the switch that sez 
> "Low Frequency Extended Range."  It introduces a small cap into the 
> doubler stage to allow for crystals down to 1.7MHz or so, IIRC.  Don't 
> quote me - all my docs are down south now.  You can see mine at 
> http://aafradio.org/flightdeck/b29.htm - about 1/4 way down the page 
> there's a closeup of the two transmitters, the bottom one being an 
> ART-13B (but without the CDA-T).

Robert Downs - Houston
<http://www.wa5cab.com> (Web Store)
MVPA 9480
<wa5cab at cs.com> (Primary email)
<wa5cab at houston.rr.com> (Backup email)