Replacement for .7 to 1 interstage transformer - Printable Version
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+--- Thread: Replacement for .7 to 1 interstage transformer (/showthread.php?tid=21737)
Replacement for .7 to 1 interstage transformer - Patrick - 10-25-2020
Had a similar thread, but it wasn’t as specific as this, and therefore got lost. Anyone know a good replacement for this interstage transformer? Has a turns ratio of .7 to 1. It’s in a Sparton 28.
[Image: https://i.imgur.com/lNO85AP.jpg]
RE: Replacement for .7 to 1 interstage transformer - morzh - 10-25-2020
It can not be .7 to 1.
Just by the sheer DC resistance, even if accounted for the wire gauge, 700 Ohm to 1 Ohm means huge difference in the number of turns.
RE: Replacement for .7 to 1 interstage transformer - Patrick - 10-25-2020
Morzh,
Look at the schematic. Primary at 3580Ω, secondary center-tapped at 2985Ω (or 5970Ω total secondary). equals a turns ratio of actually .599 to one, but close enough to the rated value of .7 to 1. Am I missing something here?
RE: Replacement for .7 to 1 interstage transformer - Patrick - 10-25-2020
Morzh,
Oh, I see. Your're looking at the output transformer. I'm referring to the input or interstage transformer.
RE: Replacement for .7 to 1 interstage transformer - morzh - 10-25-2020
Oh..yes I was looking at the output.
38-116 has a similar one.
Lets' see if Tubes and More has something.
Nope. They have 1:2 and 1:3. Can't see that ratio around.
Maybe someone else can.
RE: Replacement for .7 to 1 interstage transformer - Radioroslyn - 10-25-2020
I found a 1:1.5 but that was the lowest. Did find a 1:1 but was discontinued.
RE: Replacement for .7 to 1 interstage transformer - morzh - 10-25-2020
1:1.5 and 0.7 to 1 are close enough.
RE: Replacement for .7 to 1 interstage transformer - Radioroslyn - 10-25-2020
It's a Hammond 124D
RE: Replacement for .7 to 1 interstage transformer - Patrick - 10-25-2020
Great! Thanks Terry. I'll get a 124D and give it a shot.
Pat