Admiral T102 scored

[bandersen]

Originally Posted by Big Dave

You definitely need to do the hot chassis fix. these were notorious for the cabinets being hot despite all insulators being in place.

What's the fix ? better insulators ?

Speaker of hot chassis, there's a big 54 ohm 20W resistor running down one side to drop the filament voltage.

Here's the series wired tube lineup:

3.15 - 3BC5
4.70 - 5J6
3.15 - 3CB6
3.15 - 3CB6
6.30 - 6BA8A
4.70 - 5U8
3.15 - 3DT6
12.6 - 12CU5
6.30 - 6CM7
6.30 - 6CG7
12.6 - 12DQ6
12.6 - 12AX4GTA
6.30 - 10ABP4
----
85 @ 600mA

I plugged that into this website Reece tipped me off to and got this.

note: I used 120 for the supply voltage. If I use 117, I get 53 ohms @ 19.2 W.

* Dropper resistor = 60 ohms @ 21.6 W

* Dropper resistor with diode = 1 ohms @ 0.3 W

* Dropper capacitor = 22 uF + 17 ohms @ 6W

I like the idea of shaving off most of that wasted 20W. Has anyone tried the diode or capacitor method in a series string TV set ?