That's a very interesting comment, got me to thinking. The VR150 was
connected to a working Vax Station 3100 with the proper DEC cable and I
observed the non-working behavior. However, the color RGB output from
the VS3100 works just fine, I boot the machine into VMS and runs just OK
(but using a different monitor and video cable).
In the VS3100, at least the one I have M78, I think the monochrome video
output is separate from the RGB outputs. I wonder if that part of the
video circuit is not working correctly?
I understand your comment about the rate, the VR150 is a non-standard
video refresh rate. I think it is hard wired just for the DEC video output.
Doug
On 8/10/2020 1:37 PM, Bill Degnan via cctalk wrote:
One comment...if you don't have the correct cable and a system that is set
for the correct refresh rate, it may appear that the monitor does not
work. Be sure you have compatible equipment. This was a specialized
display.
Bill
On Mon, Aug 10, 2020 at 1:19 PM Douglas Taylor via cctalk <
cctalk@classiccmp.org> wrote:
Josh;
I have a DEC VR150 that is nearly functional; shows full screen but the
H/V are not in any sync at all. Would love to use it with a VaxStation
3100.
Opened it up and found it quite a complicated monitor, not like a simple
PC monochrome monitor.
Purchased a microfiche manual off ebay, but haven't been able to view it
yet.
Eager to hear how you do with your larger monitor.
Doug
On 8/9/2020 3:10 AM, Josh Dersch via cctech wrote:
Hi all --
Picked up a non-functional but otherwise nice looking DEC VR260 (19" b&w
monitor) on the cheap, hoping to use it with my VAXstation 2000. From
what
I've read, these were never the most reliable displays. Curious if
anyone
has any information on common failure modes, or has service docs
squirreled
away somewhere. I've at least found schematics, so I have something to
go
on, but it's not exactly the most straightforward design I've poked at.
Right now when powered up I hear a repeated low hum from the transformer
followed by a soft ticking noise so I'm guessing I've got power supply
issues at the very least. Unsure what I should expect the monitor to do
if
it's not being fed a valid video signal (I haven't yet tried to hook the
VS2000 up to it) -- whether it'll go into free-running mode or do mostly
nothing until it has something to sync to...
Thanks as always,
Josh
