Electrical Frequency Meter

Features

Specifications

• Overall Height:
  12.500 inches
• Overall Width:
  17.375 inches
• Frequency Rating:
  Between 1.0 kilohertz and 50.0 kilohertz
• Furnished Items And Quantity:
  Frequency meter fr-6/u 1, case meter cy- 1501/u 1, cord cg-409/u 1, frequency data book 1
• Frequency Response Range:
  +100.0/+500.0 megahertz
• Features Provided:
  Internal frequency calibrating crystal
• Phase:
  Single
• Functional Classification:
  Aa-6.3
• Functional Description:
  Portable instrument capable of measuring any frequency within the range of 100 to 500 mhz w/accuracy of porm 0.001 pct. Uses heterodyne principle for determining frequency of an unknown signal; measurement is accomplished by heterdyning a known signal from the test instrument against the unknown signal. Check points are used to calibrate the instrument throughout its operating range. Used to test the following avionics systems: an/akt-18; an/ara-31; an/arc-54; an/arc-60; an/arc-73; an/arn-3 (); an/crd-4; an/trc-68; an/urr-35c; r-508/arc; r-509/arc, and t-366() /arc
• Entry Date:
  70-01-09
• Reference Data And Literature:
  Dept of army publications: tm11-5096 w/changes 1 and 2, oct 55; tm11-6625-312-12p w/change 1, jul 59; tm11-6625-312-35p w/change 2, jul 59; tb11-6625-312-35/1
• Type/model Designation:
  An/urm-81
• Federal Supply Class (fsc):
  Electrical and electronic properties measuring and testing instruments
• National Stock Number (nsn):
  6625-00-539-9910