A211B tube FM Transceiver

“A” series VHF/FM field backpack transceiver is part of Sino-Soviet tech transfer pack signed in 1950.  With Soviet’s technology transfer, Chinese license produced Soviet’s R-105/108/109/114 FM field radios. Their Chinese model names are A130 (R-105, 36.0 to 46.1 MHz), A211(R-108, 28.0 to 36.5 MHz), A212(R-109, 21.5 to 28.5 MHz) and A233(R114, 20.0 to 26.0 MHz).  These four radios are basically the same radio but with different frequency range. They are defined by PLA as Regiment-Battalion level radio mainly for artillery units.  A130 was used to communicate between regimental artillery HQ to infantry units.  A211/A212 was used between regimental artillery HQ and artillery battalion HQs/artillery observation posts.  A233 was used to communicate between regimental artillery HQ and armored troops.

The A series radios are all tube radio with a mechanical vibrator unit to produced 150 V of voltages from 4.8V batteries. The A series radio came with four types of antennas, 1.5 meter wipe antenna, 2.7 meters wipe antenna (1.5 meter antenna plus 4 extension sessions), 10 meters wire antenna and 44 meters directional antenna.  Communication distance ranges from 6 km to 20km depend on antenna type and environments.  Additional to regular FM transceiver, The A series radios could also be used as a wired field telephone, or a semi/full auto repeater.

In mid-60’s, model B was introduced.  What I could tell is that a squelch mode sensitivity adjustment was added, but this sensitivity adjustment is not very sensitive.  The vibrator is still the mechanical type.  All A series radios were replaced in early to mid-70’s by 7 series all transistors VHF FM transceivers. My sample is an A211B made in 1969 with full set of accessories and spare tubes/parts.  The batteries came with my radio are long dead.  I used 8 D size 5AH NiCd rechargeable batteries to power this tube radio.   When I first turn my A211B on, no sound came out but the meter indicated the correct voltage.   I checked the manual, and it said the vibrator should make constant noise, but my radio was very quiet.  I found a new vibrator from the spare tube/parts box and replaced the old one.  Turned on the radio again, noise immediately came out of the radio from the new vibrator and static noise also flew out of headset.  My A211B is live again after over 40 years in storage.

A211B:

Type: VHF FM transceiver

Frequency: 28.0 to 36.5 MHz

Transmitting power: 1.2W

Dimension: 365X385X230 mm

Weight: 14 kg with batteries, antenna and headset

Auto receiver tracking +-10Kz

Power supply: 2 x Type 2NK24 2.4V rechargeable batteries

Tubes (12 tubes): 3 x 4J1S, 1 x 4P1S, 8 x 2J27S