The SCH ver 5 gets past three big problems with the old versions. First,
tweaking the resistor, though Wilf got rid of that. Second, the PSH had
blinking lock on lights, while the SCH didn't. Third, the **14 had
limited driving abilities. People might add a **245 as a motor driver,
but the **245 can be so much more when used as the non-Schmitt portion of
the head. Using the **245 as the driver frees up most of the **14. In
fact, there are enough free inverters to make a microcore based walker.
So now you can quickly and easily make your walker phototropic, either by
Nv influencing, or shifting the center of gravity. Using the **245 as
the non-Schmitt part makes the circuit 100% reliable under any light
level, with CDS photocells, photodiodes, or reverse biased LEDs
(pictured).

On another topic, Circad is great! I still have to erase all the extra
labels in Paint, but it sure is an improvement!

-Martin

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