[ARC5] tuning knobs (and local controls)

[jcoward5452 at aol.com]

  I have two different PL-192's . One has a completely enclosed metal 
shell and the other has a solid phenolic disk where a wire loom disk 
would ordinarily be for a PL-152-A.The solid shell has PL-192 stamped 
into the end of the shell,the phenolic disk one has PL-192 stamped into 
the shell side like the -152 and also has PL-192  stamped onto the disk 
in white ink. (BTW,they are also from A.J.Link).
  As for local controls,I have two versions of FT-260-*. The odd one has 
a toggle switch in place of the 3 positin rotary.The stamped 
nomenclature on the housing is scratched out.The labeling of the switch 
positions looks facktory and the tip of the toggle has the little glow 
bead.Not a ham job at all.Could have been an upgrade for high altitude 
gloves?
 Jay KE6PPF


-----Original Message-----
From: Mike Morrow <kk5f at earthlink.net>
To: arc5 at mailman.qth.net
Sent: Wed, 31 Dec 2008 9:51 am
Subject: Re: [ARC5] tuning knobs (and local controls)



Jack wrote:

>Another rare item for a locally controlled receiver is the
>PL-192 plug for the receiver rack. This is a jumper plug for
>the receiver rack that completes the +28 volt supply line for
>on-off switching. There is an MX-something equivalent for the
>AN/ARC-5 as well...

Excellent point!  How could I have forgotten that?  The wired
plug for the SCR-274-N is indeed rare.  In all my years, I've
come across just one PL-192, and I got that from A.J. Link.

These local control plugs make up the LV power connection from
pin 1 to 6 on the back top of receiver rack, which normally would
be made up at the remote control box.

The official AN/ARC-5 equivalent is the "A.R.C. 6787 Wired Plug".
I've never seen one.  Another plug which could be used is the
MX-2/ARR-2 that Jack refers to.  It is wired like the A.R.C. 6787,
plus it has a connection between pins 2 and 8 to connect receiver
audio output to audio bus A.  This was required for AN/ARR-2
installations using the early MT-7/ARR-2 single receiver rack,
which does NOT have an audio bus A / bus B select switch.  (That
was later added to the MT-7A.)  There are a lot of MX-2/ARR-2 plugs
around because they were used every place that the AN/ARR-2 was
was installed.  Since all AN/ARR-2 and AN/ARC-5 racks other than
the old MT-7 have audio bus switches on the rack, the AN/ARC-5
manuals say that the connection between pin 2 and 8 should be
lifted on the MX-2.  Thus it becomes electrically identical to
the A.R.C. 6787.

Mike / KK5F


_______________________________________________
ARC5 mailing list
ARC5 at mailman.qth.net
http://mailman.qth.net/mailman/listinfo/arc5