[Milsurplus] AN/URT-18 transmitter??

[Jim Whartenby]

Sure John, pictures are welcome!
I have some manuals which I would be happy to copy if that will help.  Also have 
gained some experience working on two URC-32s and one 310F-6 so I know some of 
the pitfalls.  Reworking the power supply and blower motor are first order 
issues, followed by getting the SMO back in sync.  The Interpolation Oscillator 
is the problem there.
  
You say that the frequency selector is different?  I guess that there is no 
mechanical odometer type frequency readout?  If the frequency selector is rotary 
switches then this radio could be like the 310F-1 which is an auto-tuned radio.  
Look for two servo amplifier modules, one 5 watt, one 2 watt, easily identified 
since there are two small pots on the module front.

I can take a picture of the 310F-1 to give you an idea what it looks like.  All 
is mounted on the rack except for the motor-generator.  I will have to make a 
one inch spacer for each side of the rack so that the back of the M/G assembly 
doesn't hit the plenum.
Jim


----- Original Message ----
From: John Vendely <jvendely at cfl.rr.com>
To: milsurplus at mailman.qth.net
Sent: Sat, November 13, 2010 11:24:22 AM
Subject: Re: [Milsurplus] AN/URT-18 transmitter??

Hi Jim,

Thanks for the reply.  Yes, the AN/GRR-13 has exactly the same style of 
construction as all the KWT-6 variants--the familiar light gauge metal 
covers with toggle snaps, with the entire set mounted in an open relay 
rack.  The individual chassis are designed to unlatch and swing out for 
servicing.  The frequency selector unit looks a bit different from the 
310F-6, as does the number and arrangement of subassemblies.  I always 
assumed it was merely a military nomenclatured version of a standard 
product, but I don't see anything in the Collins catalogs of the time 
which looks identical.  I really have never spent much time analyzing 
it, though I'm sure it must be just another variation on the KWT-6 
theme.  Manuals for the other variants might well serve as a guide.  
This discussion has certainly piqued my interest, and I could furnish 
some pix in case you're curious about it...

73,

John K9WT