heater center taps

[sst4270]

I'm new here. I've built several hi-fi amps and recently completed a 5E3 Deluxe. I'm in the process of building my version of a TW. I've been studying all the photographs of Francesca as well as all of your incredibly well made clones. [congrats] as well as the schematics... And my question is this:
I've never seen any mention of the two 100 ohm resistors that Francesca uses as an artificial center tap on one of the EL34 sockets.
Is this because all of you are using x-fmrs with a heater center tap?
And if so... Did Francesca's pwr x-fmr have a heater center tap that Ken chose not to use?
Furthermore the resistors are not in any of the schematics... They all show heater center tap coming off of the pwr x-fmr.
Your comments and advice would be appreciated.
-Steve

[Allynmey]

Steve, most people use Mooses trannys that have a center tap on the heaters. I've tried lifting the heaters, installing the resistors and there was no difference in hum.

Allynmey

[mhuss]

If your tranny has a heater center-tap, use it. The resistors are just a workaround for heater windings without center taps.

Elevating this center tap helps a little on high gain amps, don't know that it's needed for a TW style build.

--mark

[Krinkle]

I have the PT from Moose that has a heater CT. Where are you guys physically grounding the CT? I see that Rockstah's build has a screw added underneath the PT and he gorunds it there.

Darrin

[drhulsey]

... Where are you guys physically grounding the CT?

PT center taps are grounded with the mains ground in the back corner near the mains plug.