Linear power supply for Boss (and other) pedals

[laurie]

I've been using this type of power supply for years. I find a linear supply is far less noisy and I prefer the "old school" approach.

I've also been using these power supplies as a "buffer" between modern switched-mode plug-packs (wall warts) and older analogue pedals. Find an 18VDC switched mode wall-wart at the thrift store and use it to power one of these PSU boards. (PSU = Power Supply Unit)

When set up for 9VDC or 9.6VDC using a 7809 regulator, these boards can be powered by anything from 12VDC to 24VDC, and 12VAC to 20VAC. A non switched-mode wall-wart with a 12VDC nameplate is an excellent choice, as is an old monitor or laptop supply (typically 19VDC).

Higher supply voltages and higher output currents will necessitate bolting the 78xx regulator to a heatsink of some sort. If using D1 the tab of the 78xx will no longer be at ground potential, so an insulator between the 78xx and the heatsink will be needed if using the enclosure as a heatsink.

Currently I have a couple of these powering pedalboards - one running from an 18VDC switched-mode wall wart, and the other running from a 12VAC wall-wart. Both wall-warts from thrift stores for a couple of bucks.
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PSU_SCHEM.jpg (332.82 KiB) Viewed 2252 times

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PSU3.jpg (255.86 KiB) Viewed 2252 times

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PSU4.jpg (244.21 KiB) Viewed 2252 times

[laurie]

The unit in the pictures is set up to provide 9.6VDC at 200mA. With larger capacitors and bolting the 7809 to a heatsink these will supply over an Amp of current.

Note that the LED isn't shown - it will be installed through a hole in the aluminum case that the PSU will be mounted in.
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PSU1.jpg (384.17 KiB) Viewed 2250 times

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PSU2.jpg (359.72 KiB) Viewed 2250 times

[laurie]

I have a heap of these boards spare. Ordering 100 wasn't much more cost than ordering 5.

So ... if you are a long term member and we've "had previous interactions" (you know who you are) and you would like a couple of these boards, I'd be happy to just post them to you. Let me know by email only - if we've had interactions, you will have my email. I won't be answering DMs on here about this unless you can't find my email.

This freebie offer is just the boards, not the components. If you would like the board loaded with components, we can come to some arrangement.
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