07-10-2016, 09:03 AM
I've had no problem with any of the Ukrainian, Russian, Bulgarian suppliers of ex USSR gear on eBay. Your own mileage may vary.
All the types are really different filament currents, like old Telefunken Y8 series metal can battery vales/tubes. Not designed for overall series mode like D9x series.
All are designed for 0.8V to 1.3V rechargeable cell operation (nominal 1.2V) rather than the 1V to 1.6V of the normal dry battery valves (nominal 1.4V).
Very long life if filament voltage is carefully set. Useful operation down to 0.7V
They had several applications:
Proximity fuses in bombs, shells, missiles.
MiG fighter radar and two way radio
Early satellite and spacecraft beacons and two way radio
Military man pack and vehicle radios
At least one commercial two way radio for forestry workers.
No Domestic stuff known.
1j17b: Older version of 1j18b, not worth buying unless stupidly cheap.
1j18b: medium filament current, lower performance, older type. Good for old 1920s to early 1930s circuits. Cheapest.
1j24b: Very low filament current, about 12mA, can replace DF97, DC90, DF96, DF91 etc, but really no AGC, sharp cut-off like 1U4 or DF92. About 24V to 70V HT. Screen grid Vg2 is best gain at 55V and very low gain at 20V, so Vg2 can be used for amplified AGC in or DC gain control, like 1U4.
1j29b: higher current, series or parallel for the two filaments or even just use one for 1/2 power and 1/2 gain. Better performance as RF preamp or RF or AF power out. RF power, but can replace DL94 but at close to DL96 consumption. Can be up to 150V HT, OK at 45V.
1p24b: Very high filament current. Can be used linear, but designed for up to 800W peak! Probably three in parallel can simulate an earlier PX type triode. Really unless you are building high power class B push pull RF transmitter. HT 45V to 200V
1j37b: Simplified version of 1j18b (less shielding rods), but both g1 plates brought out rather than internally connected. Mixers, AGC, DC volume control, frequency doublers and active AM detectors etc. Simulated remote cut off. Quite high filament consumption. 12V to 90V HT. Can be used as a gammatron.
1j42a: Last ever design. Optimised for 6V HT. Works 4V to 12V, similar but not identical filament current to the 1j24b, about 12mA. Completely different design to suit the low HT. The g1 plates brought out separately like 1j37b to facilitate Mixers, AGC, DC volume control, frequency doublers and active AM detectors etc. Simulated remote cut off. Can be used as a gammatron.
1e4a: Magic Eye at about 12mA filament current. Not a rod tube and very small. Intended for use in Military sets using the Rod Tubes.
IV15, iv15: Really unrelated to Rod Tube radios. Similar idea to the DM160 VFD, http://www.radiomuseum.org/tubes/tube_dm160.html designed to be a long life lamp replacement but with on/off electrode for transistor voltages, unlike a neon. Two in series will run off one NiMH cell as they are 0.6V filament. Medium current. They will work as a low gain triode amp. Pretty.
There are also some neon based bargraphs!
All the types are really different filament currents, like old Telefunken Y8 series metal can battery vales/tubes. Not designed for overall series mode like D9x series.
All are designed for 0.8V to 1.3V rechargeable cell operation (nominal 1.2V) rather than the 1V to 1.6V of the normal dry battery valves (nominal 1.4V).
Very long life if filament voltage is carefully set. Useful operation down to 0.7V
They had several applications:
Proximity fuses in bombs, shells, missiles.
MiG fighter radar and two way radio
Early satellite and spacecraft beacons and two way radio
Military man pack and vehicle radios
At least one commercial two way radio for forestry workers.
No Domestic stuff known.
1j17b: Older version of 1j18b, not worth buying unless stupidly cheap.
1j18b: medium filament current, lower performance, older type. Good for old 1920s to early 1930s circuits. Cheapest.
1j24b: Very low filament current, about 12mA, can replace DF97, DC90, DF96, DF91 etc, but really no AGC, sharp cut-off like 1U4 or DF92. About 24V to 70V HT. Screen grid Vg2 is best gain at 55V and very low gain at 20V, so Vg2 can be used for amplified AGC in or DC gain control, like 1U4.
1j29b: higher current, series or parallel for the two filaments or even just use one for 1/2 power and 1/2 gain. Better performance as RF preamp or RF or AF power out. RF power, but can replace DL94 but at close to DL96 consumption. Can be up to 150V HT, OK at 45V.
1p24b: Very high filament current. Can be used linear, but designed for up to 800W peak! Probably three in parallel can simulate an earlier PX type triode. Really unless you are building high power class B push pull RF transmitter. HT 45V to 200V
1j37b: Simplified version of 1j18b (less shielding rods), but both g1 plates brought out rather than internally connected. Mixers, AGC, DC volume control, frequency doublers and active AM detectors etc. Simulated remote cut off. Quite high filament consumption. 12V to 90V HT. Can be used as a gammatron.
1j42a: Last ever design. Optimised for 6V HT. Works 4V to 12V, similar but not identical filament current to the 1j24b, about 12mA. Completely different design to suit the low HT. The g1 plates brought out separately like 1j37b to facilitate Mixers, AGC, DC volume control, frequency doublers and active AM detectors etc. Simulated remote cut off. Can be used as a gammatron.
1e4a: Magic Eye at about 12mA filament current. Not a rod tube and very small. Intended for use in Military sets using the Rod Tubes.
IV15, iv15: Really unrelated to Rod Tube radios. Similar idea to the DM160 VFD, http://www.radiomuseum.org/tubes/tube_dm160.html designed to be a long life lamp replacement but with on/off electrode for transistor voltages, unlike a neon. Two in series will run off one NiMH cell as they are 0.6V filament. Medium current. They will work as a low gain triode amp. Pretty.
There are also some neon based bargraphs!
