02-08-2020, 09:57 AM
Here you can see that an outer sleeve of about the same diameter as a B7G valve is possible, but more height is needed.
Replacement of any series type, 25mA or 50 mA will need a parallel ballast resistor. Though the datasheet shows 13mA for the glow current (literal Russian for filament) it's closer to 11mA for a1.25V supply. The 25mA and 50mA is also a nominal value. I need to measure some DK91/1R5, 1L6, DK92 and DK96 at typical series voltages / currents to see what voltage to set on the triode-pentode, measure actual current at that voltage and then calculate the ballast resistors.
A variable capacitor had the two rotor pins soldered to the screen and stator to the exposed anode wire connection / join on the mixer pentode to allow adjustment of capacitance to peak the IFT tuned for a DK96.
Replacement of any series type, 25mA or 50 mA will need a parallel ballast resistor. Though the datasheet shows 13mA for the glow current (literal Russian for filament) it's closer to 11mA for a1.25V supply. The 25mA and 50mA is also a nominal value. I need to measure some DK91/1R5, 1L6, DK92 and DK96 at typical series voltages / currents to see what voltage to set on the triode-pentode, measure actual current at that voltage and then calculate the ballast resistors.
A variable capacitor had the two rotor pins soldered to the screen and stator to the exposed anode wire connection / join on the mixer pentode to allow adjustment of capacitance to peak the IFT tuned for a DK96.
