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AN/GRC-9 Radio Set ("Angry Nine")
The AN/GRC-9 (often called the "Angry Nine") was a 2-12 MHz, AM/CW, low power transportable radio set which can be vehicular mounted (as the AN/VRC-34). It was fielded in the late 1940s and used through the Korean War and later in the 1950s. The AN/GRC-9 replaced the SCR-284, SCR-288 and SCR-694 radios and was in turn replaced by the AN/PRC-62 and AN/PRC-74.
AN/GRC-9 Radio Set System of Components
The complete AN/GRC-9 is a set of components for operation on Continuous Wave (CW), modulated CW (MCW) or AM from 2 to 12 MHz across three bands. According to TM 11-263 (1956), range is 30 miles on CW, 20 miles on MCW and 10 miles on AM (voice). Operation in a vehicle had shorter ranges, about half the above.
The main AN/GRC-9 component is the receiver-transmitter unit, RT-77/GRC-9, operating on two pre-set frequencies determined by crystal.
In addition to the electronic components, the complete system includes canvas bags, whip antenna mast with counterpoise 1/2 wave sloping wire (and erecting kit), straps, a T-17 microphone, J-45 telegraph key for CW operation, HS-30 head- set and LS-7 speaker.
AN/GRC-9 Power Options
Multiple options are provided for power supply to allow operation using 6, 12, 24 volt DC or 115/230 volt AC sources:
Other options included the GN-58 hand-cranked generator (photo, right) and the PE-162 gasoline engine generator. When operating the receiver only, BA-48 or any dry battery of proper voltage will operate the set.
AN/GRC-9 Technical Manuals
The original technical manual for these radios was TM 11-263 (Air Force TO 31R2-2GRC9-1.) Later revision was TM 11-5820-453-10 Operators Manual and TM 11-5820-453-20 Organizational Maintenance manual.
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