[ARC5] A.R.C. Types and Military Usage

[Michael Tauson]

Hi, Mike,

On 5/7/07, Mike Morrow <kk5f at earthlink.net> wrote:
> >For instance- right now on ebay there are A.R.C. ads for
> >Type 11 and for Type 21- a navigation set.

> The A.R.C. Type 21 is the commercial model number of the AN/ARN-59 ADF,
> but I suspect the principal buyer of the Type 21 was the US military, not civil
> aviation users.  I think the same is true of most of the Type 12 and Type 15
> components.  Almost every one I've seen *without* JAN nomenclature still has
> something (such as an ink stamp, military contract number, or "US" label) which
> indicates military rather than civil service.

Probably.  But then, civilian users would swap out equipment at a
radio shop on an individual basis and those shops would do any of a
number of things with them including throw them out if they lost type
certification.  When the military surplussed out equipment, they did
it wholesale numbers, not the onesy-twosy way civilians did.  As a
result, the vast majority of the equipment found on the market is
military and not civilian.

With the increase of channel density from 180 to 360 to 720, the low
power transmitters with just a few channels simply weren't practical
for civilian use.  On the other hand, the military usually used the
UHF channels and had little use for VHF as a rule.  They'd have 121.5
and a handful of others but that was it.  But even the military got
caught up in the problem with channel counts and wound up shuffling
the Type 12s off for more up to date equipment.

> Even the sale flyers that A.R.C. was publishing around 1960 list A.R.C. Type 12
> and similar units as available ONLY for sale to the government.  I suspect this
> was because these components by 1960 were considered obsolete for civil
> service, yet were still available to the government for replacement use.

I tend to agree with this.  For example, the T-11 was one of the first
civilian offerings after WW II along with the R-11 as a nav-com set.
(The "nav" part was LF/MF beacons.)  By the time 1960 rolled around,
360 channel sets were pretty much the norm as was higher power (Type
210: 15 watts vs T-11: 2 watts) which pretty much shut the older sets
out.

> My vote for the most interesting 1950s-era A.R.C. set is the Type 210, which
> used the RT-11A VHF-AM transceiver.

Late 50s ... one of the last pre-Cessna A.R.C. designs.  Possibly
*the* last, I'm not sure.

> Speaking of A.R.C. type numbers, it's always bothered me a bit to see the
> A.R.C. Type 12 noted very inaccurately as the ARC-12, or even worse, the
> AN/ARC-12.

You, me and a lot of other folks here.  Sadly, it will continue even
with a gene pool cleansing so I suppose all we can do is try to
educate the miscreants and hope for the best.

Best regards,

Michael, K3MXO/KH6