[Milsurplus] Manual advice...

[Mike Morrow]

Robert wrote:

>Although the manual says that T-412's are modified T-47A's, the original 
>CDA-T crystal controlled oscillator conversion instructions also cover 
>converting 52286 (ATC) and T-47. 

The unit that just sold a few days ago on ebay at:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5852578110

is an interesting example.

An original late-WWII style US Navy nomenclature tag is shown with a tag rivited over it that has T-412/ART-13B stamped on it.

It seems certain that this unit was originally a USN T-47/ART-13 and not a USAAF T-47A/ART-13. The main difference between the USN's T-47 and the USAAF's improved T-47A is the T-47A's vernier scale on VFO dial B which enables setting the dial in 0.1 increments (T-47A calibration books were different from T-47 calibration books because of this), and the control power/top lid interlock safety switch.

The photos of the ebay unit seem to show that the original T-47 has had the lid interlock switch and the dial B vernier scale added, just like on a T-47A, in addition to having the CDA-T installed to make it a T-412.

It appears that T-412 units, when made up from USN ATC or T-47 units, also had the major mods done that improved the T-47 to the T-47A.

Mike / KK5F