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Microphone Pre-amplifier power supply

Project description

This is a compact regulator board designed to fit in a 1 Rack unit case. While the original intention was to power a microphone pre-amplifier it could also comfortably supply a smaller mixing desk or any other device that requires +/- 15 Volts at up to 1 Amp and 48 Volts at up to 250mA.

The circuitry in this project is pretty standard, a 7815 positive regulator for the +15 volt rail, 7915 negative regulator for the -15 volt rail and a TL783 set up to regulate at 48 Volts.

Using a voltage multiplier to generate the 48V supply, this power supply only needs a regular dual 15V transformer or centre tapped 30 V transformer.

The board was designed to fit into a 1 rack unit case, Although capacitors could take the height to 38mm, so it would probably be safer to mount the PCB vertically.

Note you will need a support bracket of some sort if you do this, although you could always use the side of the case for this purpose.

There are no Fuses mounted on this PCB, this was to save space and it is strongly recommended that you mount at least an AC mains fuse on the primary side of the Transformer for safety.

One alternative version of this board would be to set it up to supply 24V for older classic microphone pre-amplifiers and 48V (for phantom power). This can be accommodated by this PCB, and the instructions for doing so are here (note this addendum is intended to be read with the reference to the standard build)

Unfortunately the cost of Electronic components and shipping from Australia is not cheap, so I am selling these as short form kits (PCB, Instructions and any programmed parts) rather than complete kits.
At the moment I am selling these through Ebay which for this project includes:
PCB and

Email if you require any more info....
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