Simply great, Andy! Thanks for sharing those tips!
Just a couple of weeks ago, I was actually wondering how easy it might be to add DC restoration (probably using a single diode) to a Portacolor set..! [To me, the lack of DC restoration just gets visually annoying after a while, plus I thought it might be amusing to built a retro-looking cabinet for a cheap DVD player specifically to attach to my PortaColors and other sets from that general era. :-) ]
Now you just need to add automatic chroma gain...
--Marty
(yes, I'm the "In Living PortaColor" website guy...)
http://www.rwhirled.com/portacolor
I'm running a bit behind in updating that page, but, eh.