Power Transformer - Am I Doing Something Stupid?

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CraigGa
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Location: Up in't north of England

Re: Power Transformer - Am I Doing Something Stupid?

Post by CraigGa »

So my replacement transformer is back in my chassis and everything is looking good so thanks everyone for confirming that the transformer was at fault not me!

On a side note,
During the transformer saga I ended up with a spare power transformer with a 100-120-230-240V primary.
Would it be feasible to use this as an auto transformer to give me a lower supply voltage (I'm in the UK on 240V) to feed my PT for the initial amp power up when I get that far?
I'd still be using the light bulb limiter of course.

Thanks
Craig
Thinking about my second build.
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martin manning
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Re: Power Transformer - Am I Doing Something Stupid?

Post by martin manning »

CraigGa wrote: Tue Sep 07, 2021 1:53 pmWould it be feasible to use this as an auto transformer to give me a lower supply voltage (I'm in the UK on 240V) to feed my PT for the initial amp power up when I get that far?
Yes, you'd basically have half voltage available, which would let you bring your capacitors up to working voltage in two steps.
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CraigGa
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Location: Up in't north of England

Re: Power Transformer - Am I Doing Something Stupid?

Post by CraigGa »

martin manning wrote: Tue Sep 07, 2021 1:59 pm Yes, you'd basically have half voltage available, which would let you bring your capacitors up to working voltage in two steps.
Thanks Martin,
That's what I was thinking but will I actually get any B+ with only half voltage on my rectifier heater?
If not could I leave the rectifier tube out and bridge it with a couple of diodes?

Craig
Thinking about my second build.
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martin manning
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Re: Power Transformer - Am I Doing Something Stupid?

Post by martin manning »

I think you will get something with half voltage on the rectifier filament. Maybe add silicon diodes as the next step?
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CraigGa
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Location: Up in't north of England

Re: Power Transformer - Am I Doing Something Stupid?

Post by CraigGa »

Thanks Martin,

I can get back on with build now.
While I was waiting for the new transformer, Sod's law struck and my trusty old soldering iron died on me!

Craig
Thinking about my second build.
thetragichero
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Re: Power Transformer - Am I Doing Something Stupid?

Post by thetragichero »

it's so nice to see a manufacturer (even in a niche industry such as ours) stand behind their product like that. i'm glad you got it sorted!
PRR wrote: Plotting loadlines is only for the truly desperate, or terminally bored.
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