[GreenKeys] GNT punch on eBay

[Tom Jennings]

I believe that all of this vintage GNTs have 8-level punch blocks, but
most come with 5-level EPROMs, that never exercise the other bits.

My GNT 3501 (3601?) came this way; I contacted GNT, who put me in touch
some some outfit that sold me the ASCII, 8-bit EPROM. This was about 8
yrs ago. Mine started out as a TWX/Telex-capable reader/punch and is now
100% 8-bit. (Of course I can feed 11/16" tape still, flip the tape-width
thing, and send the right codes to punch 5-level tapes.)

If I had an EPROM reader I'd gladly make copies.