Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: acheld on July 26, 2021, 03:19:00 pm

Title: Hammond transformer primaries
Post by: acheld on July 26, 2021, 03:19:00 pm

I am curious about the purpose of the "Orange" wire which is present on the primary side of a Hammond 290DX.   What is it for?   I have no plans to use it, but Hammond does not put arbitrary wires in their products . . .

Title: Re: Hammond transformer primaries
Post by: Joel on July 26, 2021, 04:01:55 pm

EMI shield.  Its connected to a copper band that surrounds the coils.

Title: Re: Hammond transformer primaries
Post by: acheld on July 26, 2021, 05:06:43 pm

Quote from: Joel on July 26, 2021, 04:01:55 pm

EMI shield.  Its connected to a copper band that surrounds the coils.

Should I ground the orange wire to the chassis?   I figured the transformer was grounded via the mounting bolts.

Title: Re: Hammond transformer primaries
Post by: sluckey on July 26, 2021, 07:02:47 pm

Quote from: acheld on July 26, 2021, 05:06:43 pm

Should I ground the orange wire to the chassis?

yes