After I wrote the first message I ran a quick experiment adding the pullup I
alluded to in the previous message. It looks like this:

>
>
>          +--------+24
>          |         |
>          |       Load
>          Rc        |
>          |         C
>          |        /
>          +--Rb2--B
>          |        \
>          C         E
>         /          |
> PIC-Rb-B         GND
>         \
>          E
>          |
>         GND

It worked as expected. Rc causes the load transistor to conduct. When the
input is pulled to +5, the switch transistor conducts pulling the base of
the load transistor low causing the load transistor to turn off.

I'm still interested if the switching transitior in the arrangement above
is saturated or if it's conducting in the linear region. But since it
works, I'm going to roll with it.

The Rb2 was already in place from the original circuit. It didn't seem to
have any adverse effect.

BAJ

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