QCX+ Polarity

Equipment Radios & Power
1

Hello All;

Basic question here. I’m troubleshooting a friend’s QRP Labs QCX+ and nowhere on the device or in the documentation can I find the polarity of the DC jack in. I suppose if I could read the schematics I could figure it out, but I want to make sure as it isn’t my rig. I would guess it is a center positive jack like most stuff, but I don’t want to guess, although I see it is protected from reverse polarity by a diode

TIA
Eric
KG6MZS

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2

Yes, the center is + .GL!

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3

Another way to find out is to use a multimeter and measure resistance between the bnc shield and any of the two pins on a barrel plug inserted into the QCX. The one with near 0 Ohm resistance is the correct one to connect the negative terminal to :slight_smile:

73,

Wouter Jan OE/PE4WJ

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