synergetix@HOME.COM wrote:

> I need to use a PIC I/O line as a simple SPST switch, but I would
> rather use something lighter than a relay.  Would a 4066 work?

  Equivalent circuit of a 4066 is approximately a contact in series with
a 150 ohm resistor.  It isn't entirely linear either.  For a 74HC4066, I
think it's nearer 50 ohms (I suppose I could look it up at:
http://www.st.com/stonline/books/pdf/docs/1968.pdf - Yep, it *is* 50
ohms nominal ).

> If so, is there any interfacing circuitry required between the CMOS
> and the PIC?  (I'd rather ask before blowing any more parts, as my
> electronic habit is driving me into debt)

  No interface - as long as you only wish to switch voltages within the
5V supply voltage range you are using for both.  Actually, I am
surprised to find the Signetics "HC" part is rated to 12 volts; but to
use that you have to switch with 12V CMOS logic; would require level
conversion from a PIC.
--
  Cheers,
        Paul B.