Can I use a halogen transformer as a power supply?
Listen to Spehro.

If you'd rather do things the hard way, take the transformer output and run it through a full-wave rectifier. Filter the output with a large (say, 10000 uF) capacitor, then drop the resulting 15 - 18 volts through a regulator (linear or switching).







simulate this circuit &ndash; Schematic created using CircuitLab

Note that the diodes must be power rectifiers, not signal diodes.

If you're planning on using the transformer with 110 VAC in, this may not work. If you draw several amps and load the transformer to 10.5 / 2 volts AC, the diode drops will probably keep the capacitor voltage too low, unless you are careful to use a LDO (Low DropOut) regulator.