[Milsurplus] ARC-5 Receiver and other tube questions

[Mike Morrow]

>Wasn't the ARC-5/BC-45x series of HF Command Sets made obsolete
>by the British/TR-1143 design SCR-522 crystal controlled
>channelized VHF Command Sets?

To be fair, Bendix did quite a significant revision of the original
British design.  With certainty, the SCR-522-A was one of the most
important command sets of WWII, especially in the ETO.  It was even
used in some USN patrol aircraft in the PTO.

About the time of SCR-522-A deployment, the USN was using the WE
233 four-channel limited frequency coverage set that became the AN/ARC-4.
W.E. Co. developed the VHF units of the AN/ARC-5 for the USN.  Late
in WWII the VHF AN/ARC-1 entered USN service, and the VHF AN/ARC-3
entered USAAF service.

I think the best of the lot was the AN/ARC-3, which when working OK
is very simple to re-channel with its largely automatic tuning system.
A WWII ETO radio tech told me years ago that the SCR-522-A was very
aggravating to re-channel, and drifted after setting as well due to
aircraft temperature changes.

In USN service, a common AN/ARC-5 configuration of three receivers
typically held an R-4/ARR-2 VHF homing receiver, a lock-tuned R-26/ARC-5
HF receiver, and an R-28/ARC-4 four-channel VHF receiver.  The two
transmitters would have been something like a T-20/ARC-5 for HF and 
a T-23/ARC-5 for four-channel VHF.  One would have HF, VHF, and homing
all in one integrated radio system, even for single-seat fighters, without
any receiver dials or mode controls for the pilot to mess with, all in
about the same space and weight as the earlier MF/HF-only ARA/ATA
three-receiver, two-transmitter command set.

>If the VHF sets were available and the crystal manufacturing perfected
>earler I don't believe we would have seen the widespread production of
>HF Command sets.

I'd bet it would have cut down their numbers, but I don't think they'd all
go away.  Well, maybe they would have mostly gone away in the ETO.  But HF
appears to have been very useful in addition to VHF in the PTO, given the
distances flown.

The beacon band R-23/ARC-5 was still flying in some older USN aircraft in 
the 1970s.

The USN was pushing even before the end of WWII for UHF command sets.  The
first such set was the RT-58/ARC-12 which could slide into existing AN/ARC-1
racks, and use everything in the existing installation except the VHF antenna.
But it wasn't out until a couple of years after WWII.

Mike / KK5F