Carlsbro top 50 OT installation

[cowboy]

I bought a new output transformer for my Carlsbro 50 Top! There is no problem installing the secondary side but would want some help with the primary. There is a "dot" by the black cable on the schematic for the OT(we don't have this in europe i think), what does this mean?

Carlsbro Schematic here: http://www.chambonino.com/carlsbro/50-top.jpg

OT schematic here: http://www.magneticcomponents.net/40-18025_Stock.pdf

Thanks!
JT

[Jazz P Bass]

Transformer Phase

The dot on the transformer is indicative of the phase of the primary to the secondary. There is a dot on the secondary, also.
According to the transformer schematic, blue (primary) & black (secondary), are in phase.
I would place the Blue primary on the "lower" end of the phase inverter.
Of coarse Black secondary is at ground.

There is a cute trick to tell whether or not your primary is properly connected.
Disconnect the negative feedback & monitor the output.
While monitoring reconnect the NFB path.
If the signal increases, then your primary needs to be reversed.
Link:http://www.allaboutcircuits.com/vol_2/chpt_9/4.html

[cowboy]

Thanks! I installed the OT but there is a great hum..What can be causing the hum? Im thinking of the caps.