[Milsurplus] My rescue trip (should I play a dirge?)

[Cletus W Whitaker]

de  WB2CPN  South Central Pennsylvania   2002.05.02

The interesting thing about the NM-20B (URM-6) was the input attenuators.
We used it at Andrews AFB and in Alaska during 1955 trying to measure the
25.8 KHz teletype being send from the Alexanderson Alternator in Marion
MA.  It used six little coax type attenuators which had slip-on plugs at
both ends.  To change the attenuator value a big knob had to be pulled out
about an inch which disconnected the attenuator in use.  Then the knob was
rotated to select the new attenuator which was one of six held in a revolving
holder, (something like a 357 Magnum Revolver), and then the knob was pushed
in to complete the job.  Noise wise, it measured peaks and quasi-peaks which
I had never heard of before.  I don't remember that thing having an IF filter
wide enough to listen to the AM band very well.  It was for measuring...
         73   Clete