Hi Most of your deductions are correct. In 1983, the VT220 replaced the VT100 in text applications, with the VT240/VT241 used where remote graphics (ReGIS and Sixel) were required. So add a keyboard and monitor as per your deductions and an application generating ReGIS or Sixel output and there you have it. Rod Smallwood The DecCollector. -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of Tony Duell Sent: 22 August 2007 23:01 To: cctalk at classiccmp.org Subject: DEC VT240 terminal I've just bought the base unit (VS240) for a VT240 terminal on E-bay and know little about it (OK, I know it's a DEC graphics terminal). Perhaps somebody can enlightent me 1) One site i looked at said a VT240 is a monochrome unit, a VT241 is the colour version. Is the only difference the monitor? Can I use a colour monitor with my base unit? 2) On the back are obvious connectors for an RS232 port (DB25), current loop (8 pin mate-n-lock). There's a DE9 labelled 'PR', presumably a printer port, also RS232. A RJ11 keyboard socket, I assume an LK201 will work here (yes?). A BNC which seems ot be composite mono video. And a DA15 plug, also for a monitor. I assume a VR201 links here, or a V241 with the right cable. Also, can I connect the keybaord to, say, the back of the VR201, or do I have to use the RJ11 on the terminal itself? 3) How much is known about the insides? Of course I've taken it apart. It's really easy to get inside, just undo 2 screws on the bottom at the very front and remove the top cabinet shell (lift it up from the front). Then release 2 nylatch fasteners and lift up the metal screening cover. The PSU (a switch-mode unit) is inside the cover. Reach inside and unlug the PSU ribbon cable from the mainboard and remove the cover/PSU. The mainboard comes out by releasing 3 more nyl atch fasteners. On this board, there's an 8085, 2681 (dual serial chip), 8251 (USART, maybe used for the keybaord interface), 7220 (graphics chip) -- along with what seemms to be much the same circuitry as a Rainbow colour card, there are a couple of PALs, I've not checked to see if they're the same as the ones in the 'bow. Pletny of RAM and ROM, and some glue logic. And another 40 pin chip, DC310. For some reason this is saying 'processor' to me. Is it? -tony