Here is a cute circuit:
G to gnd and it goes off.
Tap D to G and it lights half-bright. It will stay that way for days. Easy way to test for gate leakage.
T to G is fun too.
G to
John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics
I recall your posting that one long ago—it builds up from noise like an ordinary oscillator.
Fun.
Cheers
Phil Hobbs
How about this one: On/Off with the same push button.
Jeroen Belleman
Yes. Dimmer too.
John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics
SPDT, cheating. ;)
John's original one from 2007(*) just used a lowpass RC from drain to ground, with an SPST from the gate to the capacitor. (I found it by searching for "builds up from noise", a phrase I remembered from the original discussion.)
The late great Vlad Vassilievsky memorialized it in ASCII art, which is good because the original ImageShack photo is long gone:
,---/\/\-----+----o LOAD o-- +V | | | |--' | ___ ||<-, +--o o---||--+ _|_ | --- gnd | gnd
Needs the button press to be not too long--if you press and hold, the drain goes to about +2V, depending on the device.
Cheers
Phil Hobbs
(*)"push-push on/off switch"
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