[ARC5] . Re: Why is the ARC-5 Tx rack so hard to find?

[Jim Horn]

On second thought, Robert is right.  You Can't use a keyed connector on AN/ARC-5 or SCR-274-N.  Plugging the unsed hole will work.



-----Original Message-----
From: WA5CAB <WA5CAB at cs.com>
To: zippypik <zippypik at aol.com>
Sent: Sun, Mar 13, 2016 9:51 pm
Subject: Re: [ARC5] . Re: Why is the ARC-5 Tx rack so hard to find?


All of the WW-II vintage Command Set connectors are keyed by the contact pattern, not by an external key.  If trying to use any of these 19-pin connectors on the MD-7 or control box (or for that matter on the BC-456 or BC-451), you first grind off the key.  Then you plug either Pin 1 or Pin 19 (IIRC) with anything convenient.  I've used a match stick in a pinch.

In a message dated 03/13/2016 17:59:49 PM Central Daylight Time, arc5 at mailman.qth.net writes: 

If you are going to use a BC-451 tx control box with the AN/ARC-5 you might want to compare diagrams for each and every connection on the plug.  For  instance, The Tx select function is grounded to select in both cases but is grounded by the selector switch in the BC-451 and by a relay in the MD-7 in the AN/ARC-5.
 

You might find that a copy of the pamphlet "A Users Guide To Aircraft Radio Corporation Receivers would be useful when dealing with AN/ARC-5, ATA, SCR-274-N, AN/ARC-60, A.R.C. Type 15 &A.R.C. type 12 (Not AN/ARC-12) equipments.
 

There exists a 19 pin plug that will physically fit the AN/ARC-5, SCR-274 or ATA equipments.  The down side of this is that there are 3 different pin orientations which are determined by a locating "key". The key can be filed off but then there are a multitude of incorrect ways to plug it in and only one correct one.   It may be possible to build up a new key, in the desired location with solder.  I haven't tried it.  A.R.C. numbers for these 19 pin plugs are: 14320, 12332 &12341.
 

Also helpful are Gordon Elliot White's articles in ancient issues of CQ magazine.



Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480


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