Uploaded January 2026 | Updated September 2026, 2 weeks ago

---

First fielded in Vietnam in 1967, the AN/PRR-9 receiver and AN/PRT-4 transmitter (collectively known as the PRC-88 system) were intended to provide portable, short-range platoon and squad-level communications. While the system showed great promise in testing, it performed poorly under actual combat conditions and was quickly withdrawn from service.

Special thanks to viewer Jim Henson for sending me this unit, and to Julian Horn for helping me decipher the internal circuitry.

0:00 Intro
1:12 Other Squad Radios
1:50 PRC-88 Origins
3:14 AN/PRR-9 External Features
5:52 Heterodyne Receivers
7:27 Internal Circuitry
12:25 Operational History
13:58 Outro

Crystal Radios video: youtu.be/6HqgWcTnWTk

RT-159A/URC-4 Survival Radio video: youtu.be/6mq2jYFRl8A

SOURCES
vietnamgear.com/kit.aspx?kit=600
vietnamgear.com/kit.aspx?kit=47
vietnamgear.com/kit.aspx?kit=517
radiomanual.info/schemi/Surplus_NATO/AN-PRT-4A_AN-PRR-9_serv_TM11-5820-549-35_1969.pdf
radiomanual.info/schemi/Surplus_NATO/AN-PRT-4A_AN-PRR-9_serv_user_TM11-5820-549-12_1966.pdf
n6cc.com/prt-4-prr-9-squad-radios