[John Fields]

On Thu, 10 Nov 2011 00:51:03 -0800, DaveC wrote:

Exactly. Much easier than all these halved supplies, coupling caps and
multiple grounds.

d

So, how -- exactly -- would you create that negative voltage?

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SYMBOL Misc\\NE555 80 176 M0
SYMATTR InstName U1
SYMBOL voltage -176 368 M0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 16
SYMBOL res 896 272 M0
SYMATTR InstName R3
SYMATTR Value 1000
SYMBOL cap 336 400 M0
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SYMATTR Value 1n
SYMBOL diode 736 224 M270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D2
SYMATTR Value 1N4148
SYMBOL diode 640 352 M0
SYMATTR InstName D3
SYMATTR Value 1N4148
SYMBOL polcap 800 352 M0
SYMATTR InstName C4
SYMATTR Value 1µ
SYMBOL polcap 512 192 M90
WINDOW 0 0 32 VBottom 2
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SYMATTR InstName C2
SYMATTR Value 1µ
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SYMATTR InstName R1
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TEXT -40 536 Right 2 !.tran .01 startup uic

--
JF