On 3/25/2009 5:24 AM David spake thus:

Actually the circuit is not all that unworkable. Some
suggestions and comments:

1) Diode D1 is backwards;
2) You need a resistor in series with D1 to limit in-rush
current;
3) There is no discharge path for C1. A high value resistor
across C2 can fix that;
4) What do expect to place across the terminals labeled 24
VDC? The voltage there may have no relation to 24 volts.

Further suggestions contingent upon knowing what is at the
24 VDC connection.

Thank you for not automatically dismissing the whole thing out of hand,
as other respondents obviously did. Not helpful.

OK, answers:

1. Yeah, it's a *drawing* error. I can still not remember which way is
which, graphically speaking, for the life of me. When I actually build
stuff I check and double-check diode anode-cathode connections, and
haven't gotten it wrong once. I guess I just need a good mnemonic to
remember which way the damn arrow points.

2. OK; I presume this needs to be the same size (power capacity) as the
resistor in series with the load, right?

3. OK.

4, 5: The load would be a small annunciator device: a doorbell, chime or
other sound-generating device, *probably* operating at 18-24 volts. I'm
guessing current draw would be in the low hundreds of mA, certainly less
than half an amp. Does that help?


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