Bill Pechter wrote:
Jerome Fine
replies:
Why did DEC not make such low cost systems available for hobby
users?
Bad management, no vision. The VT103 supply barely was enough
for the 11/23 and was designed to handle stuff like hasp
printing at IBM shops via RSX11-S downloaded apps with network booting.
Jerome Fine replies:
I think the manual says 16 A on the 5 Volts and much less on the 12 volts.
About 10 years ago, just for fun, I put in a quad 11/73, 4 MBytes of
non-DEC memory, a quad ESDI controller and a DHV11. I only ran it
for 15 minutes since that was probably stretching the power supply.
As I said, the ESDI hard drives were connected to a cable out the back
and ran on their own PC power supply, each with its own fan.
Prior to that it had been running with a dual 11/73, DLV11-J, 1/2 MByte
of memory and a 3rd party MFM controller that did MSCP - a total
of 2 1/2 slots. the hard happened to be an RD53 and it was under the
tube.
Obviously, the backplane had been upgraded from 18-bits to 22-bits
by the addition of 4 wires soldered to the backplane - 8 spots for each.
I think I acquired my first VT103 around 1989. Were the VT103s
first produced around 1980? Since all four quad slots were ABAB,
that allowed up to 8 dual boards. Which was almost equal to the
BA11 with 9 slots - all ABCD.
As for DEC, they seemed to be afraid of producing something that was
was both small and inexpensive. Essentially, the VT103 was a small
but complete PDP-11 that could run any of the operating systems
quite well, especially when the backplane was upgraded to 22-bits.
Did DEC ever sell any that they had upgraded to use 22 bits
themselves?
Sincerely yours,
Jerome Fine
