16-09-2021, 07:31 PM
(This post was last modified: 16-09-2021, 07:39 PM by Mike Watterson.)
Rod pentodes were made up till the USSR ended. Some older types had production as replacement parts, often more than really needed.
It looks like it's medium power, between the 1j24b and 1p24, likely about 125mA @ 1,2V filament. Almost certainly for proximity fuze rather than a radio. Lower filament power than the 1p24 which is about 220mA, but it's for serious transmitters.
I'd think the 1j29b family is more use as a QRP.
https://pogorily.livejournal.com/47454.html
https://fido7.su.hardw.schemes.narkive.com/IoTwMdnE/14
https://mobylplus.ru/lampa-1zh26a.html Though shows a top anode wire
Polish
https://pl.wikipedia.org/wiki/Lampa_pr%C4%99cikowa
The 1j25r is very odd having only one half of the rod pentode and bottom anode.
https://www.radiomuseum.org/tubes/tube_1j25r.html
Operational life may have been rated in minutes for high power proximity fuzes, i.e. a kind of radar on bombs, shells and missiles, but in excess of life of normal 1.4V battery valves at more modest anode current and voltage, when run off 1.2V filament supply.
It looks like it's medium power, between the 1j24b and 1p24, likely about 125mA @ 1,2V filament. Almost certainly for proximity fuze rather than a radio. Lower filament power than the 1p24 which is about 220mA, but it's for serious transmitters.
I'd think the 1j29b family is more use as a QRP.
https://pogorily.livejournal.com/47454.html
https://fido7.su.hardw.schemes.narkive.com/IoTwMdnE/14
https://mobylplus.ru/lampa-1zh26a.html Though shows a top anode wire
Polish
https://pl.wikipedia.org/wiki/Lampa_pr%C4%99cikowa
The 1j25r is very odd having only one half of the rod pentode and bottom anode.
https://www.radiomuseum.org/tubes/tube_1j25r.html
Operational life may have been rated in minutes for high power proximity fuzes, i.e. a kind of radar on bombs, shells and missiles, but in excess of life of normal 1.4V battery valves at more modest anode current and voltage, when run off 1.2V filament supply.
