LD7 is a transmitting or UHF/dezimeter-wave triode intended for oscillator and RF amplifier service as specified in the approved German technical sheet.
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
1 physical section, each with unique specifications.
Section 1
Published ratings and characteristics promoted where directly established; additional values retained as parameters. Telefunken LD7 forced-air-cooled metal-ceramic decimetric-wave transmitting triode for self-excited and driven transmitters. Maximum DC anode voltage 2500 V in continuous Class B service, reduced to 1500 V for anode modulation; much higher anode pulse voltages are conditional and must not replace continuous limit. Maximum grid dissipation 3 W. Transconductance published as 18–28 mA/V at 1300 V and 150–170 mA; plate dissipation depends on cooling, with 300 W used as a documented cooling/operating example rather than an unrestricted universal limit. Nominal indirect heating 12.6 V / about 2.1 A.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
Heater Voltage
12.6 V
Published technical-data value
Heater Current
2.1 A
Published technical-data value
Published Capacitance
5.6 pF
Published technical-data value