Zane H. Healy wrote:
OK, I'm thinking of doing a wierd mod on a VT100,
just how much room is
inside one of them? I need room for a 7 1/2" x 9" x 2 1/2" board (the
2 1/2" is thanks to the heatsink and RAM), and would also like to be able
to fit in a smallish 250W PS (3 1/2" x 5 1/2" x 6"), and a 3 1/2" HD.
Jerome Fine replies:
I don't know if this information will help, but here goes:
The VT103 is based on the VT100 and used the same shell. Inside, the
power supply is a bit more powerful. There is also a small fan just under
the vent holes on the right hand side. In that same area is enough space
for a 4 * 4 Qbus backplane in addition the the normal video interface
board. To be specific, 4 quad Qbus boards can fit there.
In addition, I have also put a 5 1/4" full height hard disk drive under the
tube. I was a VERY, VERY tight squeeze as far as the width of the
drive is concerned. As for the length of the drive, there was a lot of spare
room where the cables were located. At first I used an RD51 and later
upgraded to an RD53. Since power was very limited, I normally supplied
the power to the hard drive via an external PC power supply, but for
short periods of time, I did use the VT103 power supply.
I've got 2 or 3 VT100's, but they're so
buried it's going to take a lot of
work to get to them so was hoping to get an idea if there is room first.
Basically I'm trying to build a PDP-10 into a VT100 by using an Intel
D810EMO MicroATX board.
I hope the above information in helpful.
At one point, I wanted to see how far I could push the envelope. I used
a dual M8192, a DLV11-J, a quad 4 MByte memory card (a friend attached
the extra wires to convert the 18 bit backplane to 22 bits), an RQD11-EC
(quad ESDI hard drive controller) and a DHV11. In this case, the ESDI
hard drives were attached to cables running out the back, as were the
cabinet kits for the DHV11. Power is very limited to 16 amps on the
5 Volts for the VT103. Whenever I used and ESDI hard drive, I always
used an external PC power supply for the power for the ESDI hard drive.