need help identifying primary's on my tube transformer its giving me grief and acting a little strange

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toe1111

Member
Joined
Feb 10, 2023
Messages
5
Location
Australia
hey guys how is everybody ive been really struggling to get my preamp going again,

i blew the reg and windings in my old transformer,

i built a really nice 6sn7 cascading mu follower line stage with a linier regulated high voltage supply, but originally i used a chinese unbranded transformer that was labled to be the correct current rateing i required but i suspect was fairly overstated

now after 3 months no pre i finally came across this old trimax transformer that should be 320-0-320 with filaments and 5v winding,

i have traced the winding groups as you can see in pictures bellow and those numbers on top are the ohms readings and the link is the CT,
i suspect its one of those 5ohm taps but cant be sure I'm connecting them to test on my 40w dim bulb and its lighting em up like a short another friend sugested a 200w bulb but ive had bigger on my little dim lightbulb tester and it dims slowly as the power builds up

ive also included pictures of the winding close up and colors its an old trimax transformer from the fifty's out of a trimax a54monoblock used for broadcasting
im really desperate for any help here guys no tubes in pre is like no sugar in the first morning coffee
 

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this is the closest schematic i can find but it doesn't look right to me I should add that it was running fine and giving me 320v no problems before i transferred it from chassis to chassis I'm not worried about the filaments and already know where my ht and ct for it is i just need help finding primary's
 

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primary will be low ohms, 5 to 10 maybe?

might be two of them for 120/240 in which case you will need to get the polarity right, if no output v just flip the primary leads,

320 is going to be a little hot for that circuit with about 400 volt dc,

you can fry bacon on those 6sn7's cuz everybody like bacon, xtra crispy that is, none of that limp shrimp for me,
 
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