Triad FP40-300 wiring question

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doctord02
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Triad FP40-300 wiring question

Post by doctord02 »

In an earlier thread, I asked about ways to come up with bias voltage in a 4xKT88 bass amp I am building, and someone suggested I use a Triad flatpack transformer. So it looked about perfect and I ordered it... Now I'm getting ready to wire it up and I'm confused with the directions for wiring up the secondary...

http://system.netsuite.com/core/media/m ... 7&_xt=.pdf

The document that shipped with it says to wire it in series to get 40V center tapped, I should connect taps 6 to 7 and taps 5 to 8...

So where is my center tap? Can someone thats wired one of these or something similar give me a clue? I plan on using a full-wave rectifier to generate a negative voltage of ~ -56V which should give me enough range to bias up the 4 KT88's...
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da Geezer
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Re: Triad FP40-300 wiring question

Post by da Geezer »

The document that shipped with it says to wire it in series to get 40V center tapped, I should connect taps 6 to 7 and taps 5 to 8...
That would be parallel......for series, connect 6 & 8 together & those then become your CT.....5 & 7 then become the supply connections.
doctord02
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Joined: Tue Jan 18, 2005 4:21 am
Location: Northern California
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Re: Triad FP40-300 wiring question

Post by doctord02 »

Thanks, thats what I was thinking based on the illustration. The wiring text instructions are just wrong apparently.
Jana
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Joined: Sun Sep 07, 2008 10:40 pm
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Re: Triad FP40-300 wiring question

Post by Jana »

They still haven't fixed that? I worked with those transformers 20 years ago and the diagrams were wrong then.
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