On Sat, 19 Dec 2009 08:51:01 -0700, Jim Thompson
/Snicker wrote:

snip
That was a circuit I remembered, wanted to use again, pulled it from
archive, then couldn't figure out how it worked ;-) Stewing over it,
finally it dawned, so I made it up as a teaser to see if anyone could
figure it out. So far only one person :-(

Oh, more than one person. But you don't read my posts. So you
wouldn't know. Regardless, I enjoyed this thread from you and thanks
for adding it.

Jon