[Milsurplus] R-26M/ARC-5 autotuned receiver

[Mike Hanz]

Hue Miller wrote:

>Michael, 
>Is this correct, your spot tuned receiver does NOT have an "M" suffix?
>I have a manual, somewhere, on modifying the R-26 receiver by attaching
>the tuner. This is a Navy manual but right now i do not recall its nomenclature
>format. We can maybe therefore agree that a "field modification" was not
>extraordinary. However, this raises the question for me now, did the field
>mod include labeling the receiver with an "M"? I don't see how the field 
>forces could actually do this. The one R-26M i owned (regrets) did have
>a professionally, factory labeled nameplate. But such label equipment would
>not be available to field forces.
>
>Mike (Hanz), i (mis)read ahead the same doc referenced above. The field
>trials in the last week of WW2 indicate this combo never actually saw action.
>So there was a somewhat shortened span of time this receiver would have
>been used, the constraining factors being the decreasing numbers of TB- and
>SB- aircraft in the postwar period, and the arrival of the ARR-15, when, 1948?
>

Ah!  Okay, I'm familiar with Taigh's document, Hue.  I didn't read 
anywhere in that report where a standby receiver was recommended - they 
just plopped the test receiver into a standard TBM that already had an 
ARB and R-26 in it, thus the duplicate capability for the period of the 
test.  Whatever reason(s) the Navy had for having an R-26 and ARB in the 
aircraft remained the reason(s) after the evaluation, irrespective of 
the Yardeny's success or failure.  The whole purpose of the capability 
was to eliminate the coffee grinding associated with the other available 
receivers - give the crew something else to do with their spare time 
rather than creating mischief by tuning around.   :-)   More important, 
the evaluation was 4-15 August *1944* - an entire *year* before the end 
of the war, not the last week of the war.  A year during the war was a 
lifetime in terms of equipment deployment, with a sense of urgency that 
grows dim in peacetime.  Moreover, one has to be careful about assuming 
operational test recommendations were fully implemented, or even 
considered for implementation.  For example, among a number of other 
recommendations, the report assessing operational suitability of radio 
equipment in the B-29 recommends moving the radio operator back to the 
radar compartment!  Dent happen, wasn't gonna  happen. 

The two "official" channel switching methods eventually winning out in 
operational use on the Yardeny was a simple 6 position switch that is 
pictured in the modification instructions, and the  C-188/ART-13 control 
box.  This is identical to the  C-87/ART-13 with the exception of 
eliminating the pilot light and key, and adding a special  silk screened 
channel ID around the  ten position switch knob with rectangles for 
penciling in the frequencies for the particular mission.  No power 
switch.  Similar to the one in Taigh's photo, but without the confusing 
circular arcs outside of the channel numbers.  I have a small photo of 
one about halfway down the page on my wish list at 
http://aafradio.org/sidebar/Wishlist.htm if you're interested in what it 
looks like.

Like yours, my R-26M has an Navy official nomenclature plate (but silver 
colored  lettering on black background, not blue background as in most 
ARC-5 equipment.)

73,
Mike