Phantom power sag when Go-Between is plugged in

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LetterBeacon
Posts: 7
Joined: Tue Apr 26, 2011 10:46 pm

Phantom power sag when Go-Between is plugged in

Post by LetterBeacon »

I'm adding a JLM Go-Between to my DIY pre amp. I'm using this transformer to power the power supply. It's a 15VA 0-25 0-25 toroid which gives me 50Vac when wired in series. 50 / 15 = 100mA, which I think is well within spec for phantom power.

Without the Go-Between hooked up to the power supply, power supply outputs 50Vdc. When I plug in the Go-Between the voltage at the output of the power supply drops to 32Vdc. When I plug a condenser mic into the pre amp the voltage drops further to 22Vdc.

Do you know what could be causing this?

Thank you.

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Joe Malone
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Re: Phantom power sag when Go-Between is plugged in

Post by Joe Malone »

What power supply are you using to convert the transformer ac to a regulated dc power supply?
Joe :-)
JLM Audio
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LetterBeacon
Posts: 7
Joined: Tue Apr 26, 2011 10:46 pm

Re: Phantom power sag when Go-Between is plugged in

Post by LetterBeacon »

Hi Joe,

Thanks for your reply but I have just this second solved the issue! It turns out I had wired the power transformer incorrectly.

I'm using a power supply PCB that 'ruffrecords' produces over on the Group DIY forum.

Thanks,

Matt

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