[Milsurplus] panoramas at USAF museum web site

[Mike Morrow]

Nick wrote:

> A sample - Radio Op station on a B-36J
>   http://www.nmusafvirtualtour.com/media/062/B-36J%20Radio%20Operator.html
> Great detail - you can easily zoom in and read the tuning chart on the
> ART-13 for example

I surely do not understand what I see on that tuning chart...not at all.

The transmitter is a T-412/ART-13B built on a USN T-47 or ATC (there is
no vernier scale above VFO dial B, such as there is in USAF T-47A/ART-13
units).

The tuning chart is for a transmitter with the CDA-T MF/HF crystal unit,
as shown by the A and B columns for crystal control that would only be
applicable for a CDA-T.  The frequencies are listed in the VFO column,
with associated dial B settings listed to 0.1 dial division precision.
However, lacking the vernier scale above dial B, it is very difficult
to set dial B to that precision.  Secondly, many of the dial B data
values listed are not in agreement with data found in the calibration
books for either the T-47A/ART-13 or the less-precision-capable
T-47/ART-13.

In addition, the same tuning chart shows channel 1 as set for 500 kHz,
which would one of up to four LF/MF crystals installed in the CDA-T.
Blanks on the chart exist for the other three CDA-T LF/MF crystals.
The chart lists for channel 1 a switch F setting as 3 and a dial G
setting as 971.8 (right out of the cal data for an O-17/ART-13A on
500 kHz).  However, the CDA-T does NOT have switch F and dial G.
Listing F and G data on a tuning chart for a CDA-T is pure nonsense!

I wonder if the pictured transmitter is even USAF, or just some unit
that came from who knows where to fill an empty rack.

I also wonder why the C-544/APX-6 IFF control panel is located at the
radio operator's position.  I am not bothered by the C-451/ARC-21
and C-626/ARC-27 control units being there, since the pilots had control
through the C-455/ARC-21 and C-628/ARC-27 slave control panels.  I am
unaware of anything similar for the AN/APX-6.

Sometimes re-constructions raise a lot of questions with respect to
how accurately they reflect the actual in-service configurations.

Still...interesting pictures for sure.

Mike / KK5F