Quote:
Originally Posted by Yamamaya42
Looking closer at the data for the 6AT6, it seems that it IS being used for something in the set.
The tube is... a “Duplex-Diode High-Mu Triode”
The diode part is being used for something, but not sure what, or how, it goes down to the contrast control, and to the tuner ( not shown on sams schematic, but I can see the wire in photo page 6 0074-3 )
not really sure what this does however  |
Good eye, I missed that. Those two diode plates share a common cathode with the triode section. It appears to me they are using the forward bias of those diodes as a voltage reference for the Picture(Contrast)control. That variable voltage is feed to the grids of rf and if tubes, which in turn varies the gain of those stages. Unless I'm missing something I don't believe the set has any automatic gain control, only that manual picture adjustment.