VT-71 Ballast 17A485459 in a TS-4D?

[mbates14]

Doing some more searching, I found this:

http://antiqueradios.com/forums/view...80269#p2680269

Basically states that they removed resistor E, and moved the common tie point from pin 5 to pin 6.

So technically I could swap the wires from 5, and 6, but then I lose the 22 Ohm resistor.

But according to the TS-4D schematic, that resistor is in parallel with the audio preamp tube filament.

Question is, Why? and what would happen if it was "missing"?

[dieseljeep]

Originally Posted by mbates14

Doing some more searching, I found this:

http://antiqueradios.com/forums/view...80269#p2680269

Basically states that they removed resistor E, and moved the common tie point from pin 5 to pin 6.

So technically I could swap the wires from 5, and 6, but then I lose the 22 Ohm resistor.

But according to the TS-4D schematic, that resistor is in parallel with the audio preamp tube filament.

Question is, Why? and what would happen if it was "missing"?

The 1st audio tube is at the end of the heater string in the 600ma leg.
The 6SQ7 is a 300ma tube so the resistor has to be in parallel with the heater to equal 600ma. 22 ohm and at least 2 watt.