[ARC5] RAT, RAV, ARA, and RAX Questions and Observations

[Mike Morrow]

Dave wrote:

>The Aircraft Radio Corporation RAT (12 volt) and RAT-1 (24 volt)
>set of receivers were the first production sets built in the 
>familiar "type-K" style that has become commonly known 
>as "ARC-5."  Only 50 complete sets of RAT and 50 of RAT-1
>were produced. 

The RAT/RAT-1 is an interesting set.  I'm curious about:

1.  Was there a "non-preliminary" manual issued?
2.  Are there manuals of any sort surviving today?
3.  How was the 50 set total divided between the RAT and the RAT-1?
    (The RAT-1 appears to have been notably later than the RAT, judging
      CBY-46xxx designations.  See below.)
4.  What was the year of introduction?
5.  Is there any documentation of actual aircraft installations?
6.  When did the RAV (or xRAV) appear, compared to the RAT?
7.  What are the production figures for the full eight-receiver RAV?
    (less than RAT???)

I seem to remember seeing a RAT or RAV in Tony Grogan's (W4SOE/SK)
collection several years ago, which would be the only such component that
I've ever personally seen.

>and a local-tuning crank which is black anodized, rather than the later, 
>bare aluminum crank.

Th early ARA/ATA and SCR-274-N manuals show a crank that is black
anodized. 

It's interesting to look at the CBY-46xxx designations of all these "Type-K" 
derivatives.

CBY-46083   RAT               13.5 to 20.0 MHz
CBY-46084   RAT               20.0 to 27.0 MHz
CBY-46102   RAV               0.19 to 0.55 MHz
CBY-46103   RAV               0.52 to 1.5 MHz
CBY-46104   RAV/ARA           1.5 to 3.0 MHz
CBY-46105   RAV/ARA           3.0 to 6.0 MHz
CBY-46106   RAV/ARA           6.0 to 9.1 MHz
CBY-46107   RAV               9.1 to 13.5 MHz
CBY-46108   RAV/RAT-1         13.5 to 20.0 MHz
CBY-46109   RAV/RAT-1         20.0 to 27.0 MHz
CBY-46129   ARA               0.19 to 0.55 MHz
CBY-46145   ARA               0.52 to 1.5 MHz
(The last two ARA units are identical to the equivalent RAV units except
that the loop antenna connections and switch have been deleted, only
to reappear for who knows what reason on the R-23 and -24/ARC-5.)

If any significance can be attached to the sequence of these numbers, the
RAT sets appear to be significantly earlier than any follow-on sets including
the RAT-1.  The RAT-1 units share their designations with equivalent RAV
units, just as three ARA units share their designations with the three exact
equivalent RAV units.  Doubtless, ARA was assigned to three components 
after the RAV designation, but this list would seem to imply that the RAT-1
designation did not appear until after the RAV designation.  If the RAT-1 was
earlier than the RAV, then its CBY-46xxx designations would not be in exact
sequence within and identical to those assigned to RAV units.

GE's RAX-1 (CG-46115, -46116, -46117) must have easily displaced any 
potential for wide use of the RAT-1 and RAV.  The CG-46117 (7.0 to 27.0 MHz)
alone could replace all of those odd-frequency RAV and RAT-1 units, in smaller
space and weight, with better bandspread and more versatile controls.

It may be questioned if a run of only 50 sets, divided between two systems
could be accurately called a "production" set, rather than a developmental one.
For example, the VHF SCR-274-N, produced in numbers at least 20 times greater
than the RAT, remains in my opinion clearly a developmental set that didn't achieve
actual deployment status.  But perhaps the RAT can be considered to have 
achieved production status on the same basis that even in modern times, specialized
electronic equipment such as is used for intelligence collecting seems to have one-
or two-digit serial numbers.  It is doubtful that these 13.5 to 27.0 MHz sets were
intended for communications purposes.

Mike / KK5F