problems with wiring for 9V DC power

[mordechai]

I've been following the diagram from the Beavis Audio site for wiring my negative ground pedal (http://www.beavisaudio.com/techpages/StompboxWiring) but it's not working well.  When running off battery power, everything is fine, but the moment I plug in the Boss style 9V adaptor barrel, it cuts out completely.  I can't figure out what I'm doing wrong, and I'd appreciate any help.

[JustinFun]

Sounds like you've got the positive battery and positive board connections switched - very easy to do (I usually check continuity by plugging a dc adaptor lead into the socket before i solder).

The sockets are designed so that if you plug in an adaptor, the positive connection to the battery is broken (so you don't run the battery down whilst using an adaptor).

That means if you get the two positive lugs mixed up, when you plug in an adaptor, the positive connection to the circuit is broken!

[mordechai]

Oh!  Well, that makes a lot more sense, I appreciate the explanation, Justin. 

What is the "sure fire" way to wire the DC jack so that I connect the battery and the PCB power wire to the proper lugs?  Which one is always the lug meant for the battery's +9V lead?

[Kipper4]

I go by
the positive lug in the middle is for the battery
the outer positive is for the wall wart
the other larger lug is ground

[mordechai]

Very helpful, thanks Kipper.