Installing a IEC socket on a 400 and straightening the chassis.
- Thread starter George S.
- Start date
Using Joe's method to determine ihe primary winding closest to the core of a 400 S2 transformer. Line to solid color primary wires shows 14.9 mV. Line to the striped primary shows 13.5 mV.
This transformer will be wired with the striped primaries to the Line lug on the IEC socket. The lowest mV combination should be wired as Line for lowest noise.
Careful if you do this. There's 118 VAC under those two yellow wire nuts. That black cords going to the wall outlet.
This transformer will be wired with the striped primaries to the Line lug on the IEC socket. The lowest mV combination should be wired as Line for lowest noise.
Careful if you do this. There's 118 VAC under those two yellow wire nuts. That black cords going to the wall outlet.
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So I have a question. I'm injecting a sawtooth wave into the primary winding I identified as Line in the prior exercise. I have it distorted with duty cycle so I can look at it on the secondaries and observe phase. This works excellent, as seen in the two photos. On the scope, yellow is primary and purple is secondary.
The red secondary wire with the black piece of heat shrink is in phase with the striped primary. The red secondary wire with the white heat shrink is out of phase with the striped primary.
From what I read, this is related to the phasing dots found on some transformer leads. And, doesn't matter here as these red secondary leads are going to be connected to the rectifier.
Is this true? Phase no longer matters on the secondaries in this application in regards to the rectifier and B plus and minus?
The red secondary wire with the black piece of heat shrink is in phase with the striped primary. The red secondary wire with the white heat shrink is out of phase with the striped primary.
From what I read, this is related to the phasing dots found on some transformer leads. And, doesn't matter here as these red secondary leads are going to be connected to the rectifier.
Is this true? Phase no longer matters on the secondaries in this application in regards to the rectifier and B plus and minus?
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OK. So it doesn't matter here on the amps. Thought I'd investigate this. Those toroidal transformers I ordered for the preamps will need the two independent secondary windings connected to form a center tap. Hope they have phase dots on the leads. Have read that it's best to verify they're marked correctly rather than trust they're marked correctly.
Thanks Joe, those toroidals should be here this week sometime. Hopefully have time next weekend to check them out. Did some more reading about them. Looks straight forward.
AnTek sent me a couple emails today. They said they are having issues with the epoxy potting interfering with the covers center bolt or guide. Told them to send them and I can probably make them work no problem. Later!
AnTek sent me a couple emails today. They said they are having issues with the epoxy potting interfering with the covers center bolt or guide. Told them to send them and I can probably make them work no problem. Later!
Attach a green wire from one winding to the blue wire from the other winding to create your center tap. You can see by their drawing that the phasing dot is really the wire color. Just ensure that the green and blue are from SEPARATE windings, easy to find out the 2 separate windings with your ohm meter. Same deal with the primaries. For 120V, red to red and black to black. For 240, black to red from separate windings. and 240 across the remaining red and black wires.
