Gibson eh185 output transformer

[Simmie]

I am trying to identify colors of the 3 output wires one is possibly black with white stripe one probably black the other not sure,green, yellow.  Also trying to figure out the speaker jack connections.  Is one 4 ohm then switch to 8 when echo plugs in? Any help appreciated, thanks

[sluckey]

With nothing plugged into the echo jack, the internal 8Ω speaker is connected to the top lead (8Ω) of the secondary winding. Plug in the 8Ω echo speaker and it will be in parallel with the internal 8Ω speaker and the jack switch will also connect to the 4Ω tap on the secondary. The switching jack is a Switchcraft type 13A or equivalent.

Can't help with the colors.

[Simmie]

The box speaker is 4 ohm so when you plug in the echo it needs to switch to 8  right. Just have to figure which is which. Resistance is the same between any combo.

[Simmie]

The jack that's in it

[sluckey]

The box speaker is 4 ohm so when you plug in the echo it needs to switch to 8  right.

No. That's backwards. When you plug in the echo speaker the total impedance decreases because the internal speaker is in parallel to the echo speaker. The switch jacks selects a lower impedance tap whenever the echo speaker is plugged in. Look at the schematic...

     https://el34world.com/charts/Schematics/files/Gibson/Gibson_eh_185_6j7_pre.pdf

Just have to figure which is which. Resistance is the same between any combo.

The resistance is so low that most DMMs can't measure accurately. The best way to determine which wire is which is to disconnect the three primary leads. Also disconnect the internal speaker and don't plug into the echo speaker jack. Now connect 6.3VAC from your filament string to the two primary plate leads. Assume the black secondary lead is common. Measure the small AC voltage between the secondary common lead and the other two leads. The one with the highest voltage is the 8Ω tap and the one with the lower voltage is the 4Ω tap.

[Simmie]

That has the 4 ohm box speaker on 8 ohm tap. Won't that be hard on the amp

[sluckey]

I'm just telling what the switch jack does. I don't know for sure what the impedance ratio of your OT is. Do you?

Is the echo speaker supposed to be 4Ω? What is the impedance of the internal speaker?