[Milsurplus] R-648/ARR-41

[Mike Morrow]

> ... i am looking at the ARR-41 with changed feeling now. This was
> the final “NO” vote.

That would be a decision without sound basis, IMHO.

The R-648/ARR-41 represents the ultimate level of development for military LF/MF/HF aircraft receivers of the vacuum tube era.  It is in no way an aircraft version of a R-390* or R-392/URR.  It is a relatively light-weight (32.5 lbs) 15-tube single-conversion receiver that covers 0.190 to 0.550 and 2.000 to 25.000 MHz.  It uses two RF stages and three 500 kHz IF stages with two Collins mechanical filters (6.0 and 1.4 kHz).  I've owned three of them in the past 30 years and I've found them reliable, except one with a dead mechanical filter.

It is the auxilary receiver for the AN/ARC-38*.  Many seem to have remained in service in an aircraft even after the associated AN/ARC-38* was replaced by something like a RT-648/ARC-94 (Collins 618T-2).

The USAF also used their contemporary RT-128A/ARC-21 (and RT-400/ARC-65) aircraft HF set with a R-224/ARR-36 auxilary receiver.  It uses the same model control box as the RT-128A, which requires frequency entry by setting pins on a drum.  I have an R-224, but it could serve little real purpose to try to get running.  The AN/ARR-41 has this closest competitor beat.

One does not often read disparagement of the fine little R-648.  It brings very good prices for very good reasons when one can be found for sale.  I liked the fact that the MF merchant marine band was well-covered before that all went away.  It could serve the upcoming 630m band.

Mike / KK5F