Tube VCA 1Ж24Б









The device has feedback loop which is normaled to IN2 jack, so IN2 pot controls feedback amount when nothing feed into IN2 jack and feedback switch is on. When jack feed into IN2, IN2/FEEDB pot controls IN2 level. Distortion/clean switch controls two modes with more or less distortion which amount can be trimmed with trimpots through holes at panel. Drive/IN1 pot controls IN1 level. GAIN pot controls gain offset. CV pot controls gain CV level.


Power consumption: V+ 12mA, V- 25mA.


PCB - 2mm thickness, gold platted, black mask. $25


Two panels - 10HP front & back. Anodized alu, black print. $25


Tube 1Ж24Б. $5 (I don't sell tubes without boards)


SMD parts + soldering. $10


Shipping per set: $5 - only board, $8 - board+panels.


TOTAL for complete set with shipping: $73


Paypal: info(at)


Assembled module $260 + $10 shipping.


Thread at MuffWiggler forum












Warning! No music here. Technical data.














1. Zero CV level.

Feed some signal into IN1. 1 kHz sine vawe from an oscillator will be fine. Set IN1 knob to max, set GAIN knob to 0.

Adjust 100K_CV trimpot on a board to hear nothing at out.



Some interesting facts about soviet subminiature rod tube 1Ж24Б.



Rod radio tubes, where the control electron flow is not using grids, blocks the electron flow, as in conventional tubes, and rods using electrostatic lenses that change the intensity and focus the electron beam - this is a brilliant Soviet development.


They were developed in the USSR by V. N. Avdeev (1915-1972) in 1950 and meant the most significant change in design classic from the invention of electronic amplifying triodes in 1907.


They were created for battery powered military and space equipment. The mass distribution obtained in the early 60s. They have great reliability, shock and vibration, stability parameters, durability, comparable to the transistor, and the "lamp" radiation resistance makes them ideal amplifying device to operate in conditions of radiation and cosmic rays.


Very similar tube 1П24Б was on a radio transmitter on the first soviet sputnik in 1957. These tubes were into a radios on other manned and unmanned space vehicles, including the Vostok.
Sputnik transmitted "beep-beep"'s in two channels, 20 and 40 MHz, switching between two on-board transmitters having 1П24Б in output stages. All the initial animal and human test flights in Space used the Rod Pentodes.


As far as is known they were never used in Domestic Radio, but in Military and Aerospace including "man pack" radio sets. Production is believed to have ended as late as 1991 with one estimate of 200 Million made.


All soviet army radios used these tubes too.


Sputnik-1 Vostok-1 Vostok-1 spaceship
Vostok-1 controlpanel
Army radios





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