June-28th, 2013 Revised:
Upgrade electrolytic capacitors to Rubycon brand.

Positive/Negative Adjustable Voltage Regulator Module.
Based on LM317 / LM337 Regulator IC Design, AC Input, DC Output.
Complete Series of Protections (IC Function),  Current Limiting, Thermal Shutdown and SOA Control. With Protection Diodes Circuit.

This item has been assembled, and electrical test passed.
FR-4 fiber glass PCB.
HQ terminal blocks, easy connection wires.
Rubycon USC 4700uF/50V input filtering electrolytic capacitors, and other all Rubycon YXF long life and low impedance electrolytic capacitors.
3 Amp 200V high efficiency rectifiers HER303.
28 turns precision trimmer pots.
Metal film capacitor, conducive to filtering high-frequency noise.
0V(GND) to chassis DC blocking, high-frequency equivalent short-circuit.

Input Voltage: Dual 4 to 32V AC
Output Voltage: +/- 1.25 to 37V DC
Output Current: 10mA to 1.5A
PCB Size:  91 x 68mm / 3.58 x 2.68 inch
PCB Thickness : 1.6mm / 0.063 inch
Module Size(W x L x H): 91 x 68 x 40mm / 3.58 x 2.68 x 1.57 inch.
Module Specification: http://www.audiowind.com/pdf/A-240LM.pdf, No paper  specifications, please download this document.

Note: the item is a analog regulator, no step-up function.