05-10-2016, 06:45 PM
(This post was last modified: 05-10-2016, 06:54 PM by Mike Watterson.)
Performance actually gradually deteriorates above 10V HT!
See
http://www.radiomuseum.org/tubes/tube_1j42a.html
This is seriously the oddest of the Rod Pentodes, which are pretty odd.
Datasheet English PDF here
http://www.radiomuseum.org/forum/142_dat...glish.html
If you ground g2, g3 and anode, then the two g1 grids will work in gammatron mode, with filament as cathode and one grid as grid and the other as anode (either way round).
It may be possible with a 19kHz common mode choke for filament to feed stereo multiplex to filamentary cathode and have it work both as a frequency doubler 38kHz and mix in the 38KHz L-R to g1a and g1b, and then have a single valve stereo multiplex decoder. Grundig had a one valve decoder for early stereo on exports as Majestic to USA, though the mixer part was done with semiconductor diodes as switches.
I'm transferring workshop to a different shed right now.
See
http://www.radiomuseum.org/tubes/tube_1j42a.html
This is seriously the oddest of the Rod Pentodes, which are pretty odd.
Datasheet English PDF here
http://www.radiomuseum.org/forum/142_dat...glish.html
If you ground g2, g3 and anode, then the two g1 grids will work in gammatron mode, with filament as cathode and one grid as grid and the other as anode (either way round).
It may be possible with a 19kHz common mode choke for filament to feed stereo multiplex to filamentary cathode and have it work both as a frequency doubler 38kHz and mix in the 38KHz L-R to g1a and g1b, and then have a single valve stereo multiplex decoder. Grundig had a one valve decoder for early stereo on exports as Majestic to USA, though the mixer part was done with semiconductor diodes as switches.
I'm transferring workshop to a different shed right now.
