[Milsurplus] ARR-41 Info

[Mike Morrow]

Breck wrote:

>You can find the Collins Brochure on the ARR-41 at the URL below.
>It states that the receiver was developed for the U.S. Navy under contract 
>and provides  the contract number. The Brochure was furnished to me by 
>Rockwell Collins.  Kinda blows away that BC-348 replace myth!

That's a myth I've been fighting for years!  It was very obviously just ham fantasy from the start, yet it seems that once someone sets his mind that the AN/ARR-41 replaced the BC-348, no amount of evidence to the contrary is heeded.   I'm sure there will be present and future "military radio experts" who will make this absurd claim on internet websites and in magazine articles.

The AN/ARR-41 was simply the auxillary receiver to the AN/ARC-38, which was produced by Collins for the USN at the same time as the AN/ARR-41.  The HF frequency coverage of the AN/ARR-41 and the AN/ARC-38 and their operating modes are identical.  The AN/ARC-38 is a real bear for "tuning the bands."  The master control box C-1398/ARC-38 selects the frequencies using one set of thumbwheel codes for manual frequency selection, and another set of pin codes for the memory drum in the 20-channel memory system.  Neither code system uses the actual numerical value of the frequency being selected.  A thick frequency vs. codes book is stored in a lower compartment of the master control box to tell the operator what codes are associated with the desired frequency.  The code system was not used because of any security issue, but because of practical limitations to remote frequency selection technology of that time.  This box was usually located at the radio operator's station.  A smaller control box C-1399/ARC-38 at the pilot's position could select any of the twenty channels stored at the master control box.

The AN/ARR-41 provided an easily tunable, direct frequency readout receiver matching exactly the modes and HF band coverage of the AN/ARC-38.  It was usually located near the master AN/ARC-38 control box.

Thanks for posting the Collins advertisement for the AN/ARR-41.  The photo showing an AN/ARR-41 installation is interesting.  It would be from a late era of AN/ARR-41 use.  The aircraft shown has had the original AN/ARC-38 (or more likely, the RCA USB-modified AN/ARC-38A) set(s) removed, and replaced by the AN/ARC-94, which began making its appearance in the early 1960s.  The AN/ARC-94 is the military version of the Collins 618S-2, and the AN/ARC-102 is the military version of the 618S-3.  The 618S-series is likely the most capable, long-lived, and widely distributed airborne HF set of all time, civilian and military.  The AN/ARC-94 was most often the set that replaced the AN/ARC-38/38A in the USN, but often the AN/ARR-41 remained.

The original AN/ARC-38 and AN/ARR-41 both date back to 1952.  They are US Navy systems that replaced the AN/ARC-25 (T-47/ART-13 and R-105(*)/ARR-15).  I have seen reports of AN/ARR-41 receivers in a few USAF aircraft, usually along with an AN/ARC-94, but only in aircraft that earlier in life had been USN aircraft.  The AN/ARR-41 sets were there as a sort of legacy installation.

The USAF radio sets that filled the same role at the same time as the USN's Collins AN/ARC-38 and AN/ARR-41 were the RCA AN/ARC-21 and AN/ARR-36.  The AN/ARC-21 is the set that replaced the venerable AN/ARC-8.  The AN/ARC-21, with the master control box that was normally used, is also a real bear for "tuning around," though at least the memory drum pins were set using the numerical value of the desired frequency.   Unfortunately, the associated HF auxillary receiver AN/ARR-36 also uses a control box identical to the one for the AN/ARC-21, so it was not designed for easy of tuning around, the way the USN's AN/ARR-41 was.

The RT-128A/ARC-21 is a 145 lb pressurized drum, and the R-224/ARR-36 is a 50 lb featureless remote-operated box.  Even though rated power output was about the same, total weight of the USAF's RCA system was more than 50 percent greater than the USN's equivalent Collins system.

I like studying these cold war sets almost as much as the more popular WWII sets.

Mike / KK5F