Need help understanding this transformer

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ampedup
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Need help understanding this transformer

Post by ampedup »

http://www.hammondmfg.com/166.htm I have this trans powering two gz34s in my sunn 2000s clone. My question is about the center tap. I tried hooking it to ground and it was a direct short, popping my fuse. What is it if its not a ct and should I make an artificial ct?
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randalp3000
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Re: Need help understanding this transformer

Post by randalp3000 »

I assume you're using a 5 volt trans for the heaters if so you can not use the center tap. I found this out the hard way.

More info is always helpfull.
gldtp99
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Re: Need help understanding this transformer

Post by gldtp99 »

The 5V heater circuit does not use a center tap----- look at this schematic:

http://www.webphix.com/schematic%20heav ... _2000s.pdf

Disconnect the CT from ground, insulate the running end (shrink wrap), fold it up and tie wrap it in a secure location.......................gldtp99
ampedup
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Re: Need help understanding this transformer

Post by ampedup »

whats the red/yellow wire to ground on that schematic?
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Colossal
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Re: Need help understanding this transformer

Post by Colossal »

The red/yellow wire shown on the schematic is the center tap for the high voltage secondary. If the Hammond transformer you are talking about above (you haven't said what model it is) is a 5V filament transformer then you don't want to use the center tap (on the Hammond), if it has one.
Firestorm
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Re: Need help understanding this transformer

Post by Firestorm »

ampedup wrote:whats the red/yellow wire to ground on that schematic?
Center tap on the plate supply (where you do need one). Center tap on the filament supply can't be grounded because that's the rectified +DC "output" (and can actually be used for that with directly heated rectifiers).
ampedup
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Re: Need help understanding this transformer

Post by ampedup »

Sorry, its the 166rs . thanks for the reply.
shane
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Re: Need help understanding this transformer

Post by shane »

You could use the 5V transformers CT to supply the B+ instead of coming off one leg of the 5V winding.
A lot of Hammond power trannys have a 5V CT winding.
Cheers
Shane
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