Re: Taking the 'hummm' out of a circuit

From: peterken (peter273_at_hotmail.com)
Date: 10/12/04 

Date: Tue, 12 Oct 2004 17:31:36 GMT

simple
as far as I see the output of the regulator is totally under-buffered
try putting an extra elco at the output of the reg, say 2200u something

"anonymous" <anonymous@catfarm.com> wrote in message
news:hkZ9d.212267$MQ5.19587@attbi_s52...
Im working on a power supply for some musical bits. Unfortunately its
producing a great deal of "hum" in the circuit. Is there any way to filter
out residual AC in the DC line?

What I have:

+18V (wall wart) ---->3500uF
(electrolytic) ---->.22uF--->7809--->.1uF--->out
                                     |
| |
                                     ground
ground ground

the ground is common between the wall wart and all components. There are 4
7809s in parallel at the output.

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