[Boatanchors] URT-23/RF-130 Power Conversion?

[eugene at hertzmail.com]

(I see the links broke up, so I am resending with better,contiguous
links, I hope this works!)

Hello all (preface: this is a long and boring email - please feel free
to delete!),

I am trying to get a URT-23 radio on the air. This is very similar (and
may be identical to certain versions) to the Harris RF-130 set up.
Specifically, mine was made by Stewart Warner and is a URT-23B(V).  

There much more detail I can give, but here's the gist. I am trying to
get it converted to 230vac. It originally came with a 3phase 440Vac
supply.  I am trying my best to follow documentation. I have a lot of
documentation and I am hoping to reach out to the folks on the list who
may have first hand experience with this conversion.  I have made some
progress. The shack is wired, I know how to wire the connector, I have
the RF-124 230vac power supply strapped properly. The question really
comes down to necessary changes in the RF-110A amplifier itself --
actually an AM-3924B(P)/URT. 

My issue is that the documentation seems to say different, contradictory
things. Now this may be because of the various versions of this radio
that exist and therefore different versions of the documentation.  Lets
start with some documents.

The first page to show is from a document entitled "Harris RF-124
8913-0003F Dec-1980."  The page of interest can be seen here:
<http://www.hertzmail.com/URT-23/230conversion/RF-124_8913-0003F_Dec-198
0_(pg 2-2).pdf>  This document is for the 230vac power supply and it
explains the changes that need to occur in the 110A amp when the 124 is
put into service.

Page 2-2, bottom table indicates that a Jumper A1P5 must be placed on
A1TB2.  I located A1TB2 and there seems to be a phenolic (or similar)
board with various jumpers already on it. Photo is located here:
<http://www.hertzmail.com/URT-23/230conversion/IMG_5039.JPG> Can anyone
confirm that this is in fact, the proper A1P5 jumper as referenced in
the documentation?

The next change is the hard one. The document indicates to jumper
terminal board (barrier strip) A1TB4 as according to another section of
the document.  I cannot find any such terminal board.  In fact, in two
separate and different manuals I have (one for the URT-23D and one for
the RF-110A) neither has any indication of the existence of a TB4. This
could be explained either a) my version of the radio doesn't have it and
neither do the versions of the manuals I have or b) there is a typo in
the manual.  

So I looked at a different version of RF-124 power supply manual (rf-124
8913-0003E August-1976) to see what it says.  The page of interest can
be seen here:
<http://www.hertzmail.com/URT-23/230conversion/rf-124_power_strapping_89
13-0003E_August-1976.pdf>   This document seems to generally agree with
jumpering A1TB4, but says it should be done with 1A1P4 (presumably a
jumper, but I don't have it).  

A third manual I have, from an RF-110A manual (Instruction Manual
1935-005) page 2-2
<http://www.hertzmail.com/URT-23/230conversion/rf-110_power_strapping_19
32-0005.pdf>  This page says to strap A1TB1, not A1TB4 for 230Vac! This
is yet a different terminal board than the other two documents suggest.
BUT! What I noticed is that all of the other options on that table (For
440vac, 208vac, and even 115vac 3 phase) all of these options say to
strap, not TB1 (terminal board) but T1, the transformer! And, below the
table is a diagram of how to wire transformer T1 for the different
voltages!  So, could this be a typo that says TB1 and should instead say
T1? 

Here is a photo of my transformer T1. I have added numbers next to each
terminal because they were too faint to read.
<http://www.hertzmail.com/URT-23/230conversion/T1-annotated.JPG>
Looking at this, it looks suspiciously similar to the 440vac strapping
depicted in the above manual page (bottom half). Hmmm.. Could this mean
that this is what I should be focusing on?

My second question (I bet you were wondering when that would come).  Can
anyone familiar with this radio confirm that I should in fact, be
looking to rewire this transformer and not looking for some terminal
board? Before I blow anything up, I'd rather get 100% confirmation that
I should be changing the wiring on the transformer T1, not TB1 or TB4.

And my last question.  There is a single, thick, white wire that has a
lug attached that is not attached anywhere. It looks like it might be a
ground wire, I am not sure. It is in the major bundle of cables that
connects from the inside of the case to the actual RF-110A chassis.
Here are two photos. 
<http://www.hertzmail.com/URT-23/230conversion/IMG_5043.JPG>  
<http://www.hertzmail.com/URT-23/230conversion/IMG_5044.JPG> 
Can anyone tell me where this wire attaches? Maybe you have a photo of
your so I can see? If possible, if it is a ground, I would like to
attach it to the proper screw even though there are probably several
good candidates.

And lastly, thank you all for enduring this ridiculously long email. Any
comments or suggestions (or even answers) are greatly appreciated!

If anyone is interested in seeing pictures of the setup, they are here:
<http://www.hertzmail.com/URT-23/> 

73 Eugene
PS I have also posted this on the harris list