Egnator 40

[Helmholtz]

You mean measure ACV green to green, red to red & yellow to yellow?

I don't have a schematic (please post).
But if same wire colors belong to the same winding: Yes. The idea is to measure the voltages between start and end of each winding. In case of doubt check for continuity (low resistance) between the wires without power.
I would tape all wires to a piece of wood or cardboard to prevent accidental shorts.

[Perkinsman]

I checked continuity from the 5 sets of same colored secondary wires with no power first. All pairs had continuity, pink pair did not. Resistance results: Yellow-15 ohms, Green-.3 ohms, Pink-117 ohms, Red-.2 ohms, Orange-.3 ohms. With power on (probe on each wire) Yellow-65v, Green-6.87v, Pink-680v, Red-0v, Orange-16.4v

[g1]

Sounds good. Meter continuity is not something you really want to use unless you are checking for a connection (yes/no).
The meter will have some random number (40 ohms for example) where it beeps below but not above. So you did not get a continuity beep for the pinks because it was above the value chosen for your meter. But 117 ohms is good as proven by the 680VAC there.

[The Dude]

That's good news. The transformer appears to be ok, so your current draw is elsewhere. You can reconnect the secondaries. Did you ever pull the tubes and check for current draw like I suggested in post #2?

[Perkinsman]

I corrected my last post, please read again. I am trying to determine whether this is a bad transformer since this amp has many issues regarding the PT. Here is the schematic for the power transformer. https://el34world.com/charts/Schemat...ormer_spec.pdf

[Perkinsman]

I pulled all tubes & still have a rising current

[The Dude]

Here's a pic of the transformer I/O diagram from your pdf. It looks like you have all of the right voltages on all 4 taps. Not sure what the red is? Also, the fact that it powered up and didn't blow a fuse with secondaries unhooked indicates that the transformer is likely good. See my post #19.

[The Dude]

Do you have a schematic? If so, please upload it. If not, I'd next check rectifiers for shorts.

[The Dude]

Does it blow the fuse/draw excessive current even if the amp is in standby mode, or only after B+ is applied? That may help us narrow it down.

[The Dude]

I'm not saying this is the problem, but just passing it along. While looking for a schematic, I found a couple of folks who had this cap go bad (see pics). If the amp only blows fuse or draws excessive current when out of standby, it could be this.

[Perkinsman]

I'm not saying this is the problem, but just passing it along. While looking for a schematic, I found a couple of folks who had this cap go bad (see pics). If the amp only blows fuse or draws excessive current when out of standby, it could be this.

[ATTACH=CONFIG]57175[/ATTACH]
[ATTACH=CONFIG]57176[/ATTACH]

The current rises with standby off or on. I've been hunting for a schematic & only found one for what they call the Power Section which I'll attach. I attached the power transformer schematic in an earlier post.

[Perkinsman]

I checked continuity from the 5 sets of same colored secondary wires with no power first. All pairs had continuity, pink pair did not. Resistance results: Yellow-15 ohms, Green-.3 ohms, Pink-117 ohms, Red-.2 ohms, Orange-.3 ohms. With power on (probe on each wire) Yellow-65v, Green-6.87v, Pink-680v, Red-0v, Orange-16.4v

Before moving on, can someone please tell me whether the transformer is good/bad based on the info above?

[Mick Bailey]

Did the transformer pull excessive current with the secondaries disconnected? If not the problem lies elsewhere, as your voltages read fine.

[Helmholtz]

The current rises with standby off or on.

As there is no influence of the standby switch, there shouldn't be a problem in the HT circuit. Now disconnect the other two PT secondaries one after the other and watch mains current.

Edit: Please ignore post. I was referring to wrong schematic in post #25.

[Perkinsman]

As there is no influence of the standby switch, there shouldn't be a problem in the HT circuit. Now disconnect the other two PT secondaries one after the other and watch mains current.

I'm not sure what you mean by "other two PT secondaries". There are 5 pairs (same color). Are you saying to pull each pair one at a time to see whether the current rises. If so, do I pull each pair and if it doesnt rise, plug them back in & move on to the next pair?