Vacuum Tube - 6KD8 / 6U8A, Triode, Pentode
New-Old-Stock (NOS) tube.
The 6KD8 is a medium mu triode and sharp cutoff pentode in the 9 pin miniature construction. It is intended for use as a combined VHF oscillator and mixer in television receivers.
Grid 1 to cathode spacing on the 6KD8 is of such low order of magnitude as to preclude the use of voltage between the elements of more than 100 volts DC or peak AC in commercial tube checkers and shorts indicating devices, particularly where mechanical excitation of the tube is employed.