[sdiy] Anyone recognize this schematic? It's a transistor ladder with PNPs...

[lanterma at ece.gatech.edu]

I found this interesting schematic while I was sorting through files - but I can't remember where I got it from, and my google fu has failed me!

http://users.ece.gatech.edu/~lanterma/ems11/CFR_ladder.gif

Did one of y'all draw this?

Anyone recognize the handwriting?

Or the particular circuit?

Almost every Moog transistor ladder VCF uses NPNs, but this one (whatever it is) uses PNPs.

- Aaron