Tip (White) is the power supply for the enclosed preamp. 5v to 9v seems to work.
Ring (Black) is the line-level output from the preamp.
Sleeve (Shield) is Ground
Use a 9 volt battery, a Stereo 1/4" Jack for the line out, and an enclosure. Cut off and toss the elongated mini TRS.
Make the following Connections:
1. Black from the PlainTalk to 1/4" Tip.
2. White from the PlainTalk to + side of 9volt battery
3. Shield Ground Wire from the PlainTalk to 1/4" Sleeve.
4. Negative side of 9 volt battery to 1/4" Ring. When a Mono Phone plug is inserted into the 1/4" Jack the Ring will connect to the Sleeve completing the circuit with the battery.