AN/PRC 77 Radio Set is a manpack, portable VHF FM combat-net radio transceiver manufactured by "Associated Industries" and used to provide short-range, two-way radiotelephone voice communication. It can provide secure voice (X-mode) transmission with the TSEC/KY-57. The radio consists of the RT-841 transceiver and minor components. In the Joint Electronics Type Designation System (JETDS), AN/PRC translates to "Army/Navy, Portable Radio, Communication."
The AN/PRC 77 entered service during the Vietnam War (circa 1968) as an upgrade to the earlier AN/PRC 25. Today it has largely been replaced by SINCGARS radios, but the AN/PRC 77 is still capable of inter-operating with most VHF radios used by U.S. and Allied ground forces. It is not compatible with the SINCGARS frequency hopping mode. It can be used with the KY-57 voice encryption device for secure communications.
The PRC-77 differs from its predecessor, the PRC-25, mainly in that its final power amplifier stage is solid state and not vacuum tubes.
|Channels:||920 channels across two bands using 50 kHz steps|
|Frequency Ranges:|| 30.00 to 52.95 MHz (Low Channel);|
53.00 to 75.95 MHz (High Channel)
|Estimated Range:||8 km (5 mi) Dependent on conditions|
|Power Output:||1.5w to 2.0w|
|Power Source:|| BA-4386/U, BA-398/U or BA-55984 |
or a Nickel-cadmium rechargeable battery cassette.
|Antenna:|| AT-271A/PRC 10 ft. multi-section whip "Static" Whip-a-way, or|
AT-892/PRL-24 3 ft. semi-rigid steel tape "Bush-whip",
|Type of Service:|| 30K0F3E|
Manpack Field Radio
|Weight:||6.24 kg (13.75 lb)|
|Note:|| A modified version of the AN/PRC-77 is available and is designated|
AN/PRC-1177. This version has been enhanced to allow a smaller
channel step of 25 kHz and to reduce voice bandwidth to 6 kHz. These
features combine to double the number of available channels to 1840.
The only army still using the AN/PRC-77 as a main source of radio communication for regular forces is the Norwegian Army, but a radio set called MRR (Multi Role Radio) is being used by special forces and prioritized units like Telemark battalion
The Austrian Army still uses the AN/PRC-77, though it seems as if it is only used for training cadets in radio communications. For border patrol the Austrian Army now uses a new device called "TFF-41", which is capable of frequency-hopping and digital encryption. The Austrian Army also uses the AN/PRC-1177 for example the Austrian AN/PRC-77 have a special switch for a 25 kHz mode, which reduces the bandwidth of the selected channel by 25 kHz and therefore doubles the number of available channels.
In the Swedish Defense Force the radio system goes under the name Radio 145 and Radio 146 (Ra145/146), predominantly the Homeguard (State militia) is issued the Ra145/146.
The Pakistan Army has also used the set for the past 25+ years. Purchased from different sources including the US, Brazil and Spain, it is scheduled to be replaced in the next 5 years.
The Finnish army uses this radio as a "battalion radio", using it as a common training device. The radio is designated LV 217 'Ventti-seiska' (ventti being the Finnish word for Black Jack  and seiska is the slang term for seven). The army also uses a modernized version designated LV 217 M.