Filament grounding

[Frankie]

Why did Had ground the filaments with 120 r resistors. The ceriatone layout don`t show any resistors on the filaments.

[David Root]

Does the Ceriatone power transformer have a center tap on the heater winding that is grounded to the chassis? If it does that is doing essentially the same thing.

[Frankie]

Does the Ceriatone power transformer have a center tap on the heater winding that is grounded to the chassis? If it does that is doing essentially the same thing.

Yes it has a center tap to ground. but I`m not building a ceriatone, just looking at the layout, and on the hammond PT I use(290FEX), I´m not sure if there are center tap. Do I need to use those resistors to ground if I don`t have a center tap?

[Structo]

You need to be clear about which amp you are referring to.

There isn't just one Dumble amp.

[Frankie]

You need to be clear about which amp you are referring to.

There isn't just one Dumble amp. :wink:

I`m building a ODS, 100w, el 34, non hrm, Hammond Twin, dual showman PT, hammond Marshall OT. Pretty much a #0124 on the preamp side. skyliner tonestack.

[Deric]

According to Hammond's web-site there is no heater center tap on the 290FEX transformer.

http://www.hammondmfg.com/pdf/EDB291FEX.pdf

[Frankie]

According to Hammond's web-site there is no heater center tap on the 290FEX transformer.

http://www.hammondmfg.com/pdf/EDB291FEX.pdf

Thanks!
Anyone who knows what the org wire are for. I did ground that one. Is that correct!

[Deric]

The orange is a shield. It should be grounded.

[Frankie]

The orange is a shield. It should be grounded.

Thanks again! :)

Frank.

[Frankie]

The orange is a shield. It should be grounded.

Thanks again! :)

Frank.