What is a SG-25 vs URM-25D

[Rob Dunn]

Hi All,

Quick question for the group.  I had a couple of boatanchor signal
generators follow me home yesterday and am trying to figure out what I have.
The first one had the following markings on it:

TRAD
Standard Signal Generator
Model SG-25   S/N 778
10 KC - 50 MC
Supply: 115V 1ph  50 to 1000 cps
Winslow Electronics Inc.
Ansbury Park, New Jersey


 This SG-25 looks like a URM-25D and in fact the lid is apparently from a
URN-25D as it has the 5:1 attenuator, the 10:1 attenuator, the antenna
simulator and an impedance adapter along with a few jumpers included in the
lid and all are marked URM-25D.  A very old and faded set of thermal
photocopy pages with URM-25D calibration procedures was also tucked in the
lid.

My question is what is the difference between the URM-25D and the SG-25?  I
guess a second question is what is TRAD?  It is in big red letters on the
metal tag above all the other nomenclature.  I have a HP-606B that I use now
but one can never pass up a good piece of boatanchor gear.

I also have questions about a Hickok 156 "Traceometer", a General Radio
1001-A 5 KC - 50 MC Standard Signal Generator, and an Acton Type 310B
Z-Angle Meter (Some Sort of Impedance Bridge) but haven't  had much of a
chance to look at them.

Thanks

Rob