> The triac only turns off when there is no /current/ flowing through the
> junction in either direction.  The TV may well be providing enough
> inductive kickback each AC cycle to prevent the proper turn off of the
> triac.

A TV, monitor, or computer SMPSU will have capacitive lead in the current
so there is no inductive kickback from it. However the triac/thyristor
must be steered with DC (on all the time it is to be on) because the real
conduction angle of the rectifier bridge in the smpsu can be as low as 0.5
degrees at low load. This means using a lot of power for the gate (a lot
when compared with what the PIC needs). Also as Spehro said the triac gate
becomes a voltage source when the triac is on. But I think that trouble is
jamming from the monitor to the IR receiver.

Peter

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