Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Tsquared on March 24, 2012, 04:13:34 pm

Title: Help Confirm OT wiring on Classictone JTM45 OT
Post by: Tsquared on March 24, 2012, 04:13:34 pm

I think I may have wired my OT wrong... SO

Which is the center tap on the primary? I'm not sure what the black dot next to the black primary lead means in the wiring spec sheet from Magnetic Components, but I assumed the center tap was the brown wire for some reason.
 Here is a link to the diagram: http://www.classictone.net/40-18039.pdf (http://www.classictone.net/40-18039.pdf)
Can anybody confirm the correct wiring, PLEASE??? I'm starting to go nuts!

Thanks,

Tod

Title: Re: Help Confirm OT wiring on Classictone JTM45 OT
Post by: TIMBO on March 24, 2012, 05:04:49 pm

Hi T2, Black wire, black dot to me is the more - side(i connect this to the power tube that is connected to the second side of the PI triode) Brown is CT (usually connected to A node) and Red more + side ( connected to the power tube that is connected to the first side of the PI triode) and Yellow is your -,ground for the speaker.

I don't know if the two PI triodes are split into + and - but this is how i see it. Thanks

Title: Re: Help Confirm OT wiring on Classictone JTM45 OT
Post by: sluckey on March 24, 2012, 07:17:56 pm

Quote

I assumed the center tap

It is. for that OT.

The black dots (notice one by the yel secondary wire too) are phase indicators. IE, when the AC signal on the black primary is swinging positive, the AC signal on the yellow secondary will be swinging positive also. IOW the signal on the yellow wire is in phase with the signal on the black wire.