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This Post Has Been Edited by the Author
In Reply to: RE: II. Power Supply posted by Garg0yle on December 06, 2014 at 18:04:02
The Classic Hammond 200 Series power transformers now are made with 115 VAC AND 125 VAC taps on the primary. If your home's line voltage is a typical 122 VAC, and you use the 115 VAC primary winding, you get a 1.0608 step up ratio. This makes the 350-0-360 VAC winding a 373.1 VAC winding, nominal.Also, you used 165 Ohms as the PSUD PT DCR. That, without looking, is likely the end to end ( 350 - 350 VAC ) total winding. On such a center tapped transformer, you only use EITHER end to center tap as the DCR.
But wait, it gets better, you can be more precise, and should be. You can measure the DCR of the primary, and the step up ratio of the primary winding, to the High Voltage secondary winding, to determine the "best " DCR numbers to input into PSUD 2.
I will look for that Formula and post it herein.
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Hi Jeff!
When you work with Duncan amps PSU Designer II, please use the formula for Rtransformer:
Rtr. = Rsec. + (n x n x Rprim.)
Rsec. = DC Resistance secondary [Ohm], measured between (0V - high volt) of one 'leg'.
n = step-up ratio (= voltage secundary / voltage primary)
Rprim. = DC Resistance primary [Ohm]
This is the transformer resistance as it's 'seen' by the rectifier
tube.
Jeff Medwin
Edits: 12/07/14Follow Ups:
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