Apologies if this comes out of thread.. 

Thank you all, I truly appreciate it.  Still on the hunt, unless I can convince Nick or Brown to relinquish theirs ;).

I THINK the "uncommon" things I would need to source to build one would be the two filters in assembly A6 and the relay.  That said, I'm trying to follow the latter's path and understand what exactly it does when energized. 
Correct me if I'm wrong, but it seems:

1. AC comes in via the box, traverses the filters in A6 and then enters the amplifier.
2. AC comes out of the amplifier on pins R and S of the 41 position connector
   - S supplies common to all connected units
   - R supplies 115 to both the transmitter and receiver as well as the "left" side of the relay.  Someone please educate me here if there's better nomenclature here.
3. This is where I begin to get lost.  I ASSume that when 28V is applied to pin M of the transmitter, that energizes the coil of the relay, making the circuit and applying 20V to pin T of the amplifier for the carrier.

Bear with me here a moment.  My understanding of relays is that the coil has a minimum voltage requirement to make the circuit.  I ASSume here that's at least(?) 20V?  If pin T is expecting 20V for the carrier, then if/when the relay makes, wouldn't that effectively be 28V from its input?  

On Thu, Oct 2, 2025 at 4:22 PM Reuben Popp <reuben.popp@gmail.com> wrote:
Hey all,

I come seeking some help from those of you who have been into collecting and rebuilding these radios for far longer than I.  I am, short of an exciter parts unit, short one piece from having most of an AN/WRC-1 system to rebuild.  That's the exciter, the receiver, the amplifier, the antenna tuner, and the handset.  What I am missing is the interconnect box (NSN 5895-00-973-1063).  Last year one was quoted to me from a logistics supply house for 24K.  YEOW!  There's pay to play and then there's where'd my kidney, spleen and lung go?

Anyway.. I look all the time  trying to find one.. any time I head to the hamfest, or on ebay, craigslist, you name it.. no dice.  Columbia Electronics doesn't have one, Murphy's told me maybe if I had asked about 30 years ago, and Surplus Sales of Nebraska said we won't know until it gets unburied (if it exists) in the warehouse.

So, my question to you is, in your time of having done this, how have you gotten over this hurdle?  The TM has the specs for the box.. at least the dimensions of it, so I could have one made, or fab it myself.. of course that also means having to try and source another set of connectors for the cabling in/out as well as building its innards.  At this point of waiting, I'm beginning to think this is my only real chance of finding one, unless one of you happen to have one squirred away, lol.

Any suggestions?  Thanks, and 73
Reuben