- VCF East 2023 - April 14-16 - InfoAge Science and History Museums, Wall, NJ
- VCF Southwest 2023 - June 23 - 25 - Davidson-Gundy Alumni Center at University of Texas, Dallas, TX
- VCF Midwest 2023 - September 9, 10. More info to come
- VCF West 2023 - August 5, 6 (Tentative dates). More info to come
-
Please review our updated Terms and Rules here
Need advice on DEC RAINBOW adapter
- Thread starter VERAULT
- Start date
VERAULT
Veteran Member
Well I now have a real VR201 monitor. So my next step is taking this broken membrane DEC LK201AA keyboard and seeing if I can repair it. IF I disconnect the membrane from the keyboard PCB I dont get the error. So there is a pretty good chance I may be able to repair it.
So if my LK201 works perfectly fine on a VT320, but I get that Keyboard Erro 13 on the Rainbow... where do I look, the Motherboard? The cables have all been swapped with alternates... Keyboard and the 15 PIN. Maybe the IO chips on the MOBO that bring the signals in and out?
VERAULT
Veteran Member
Hmm thats strange. What kind of monitor are you using on the rainbow?
Radix
Experienced Member
Just a bit of information from back in the 80s when LK201 were current... There was a DIRE warning from DEC about NOT using normal telephone curly cords to replace the LK201 cables, if they got damaged...
Many telephone cables are "tinsel cable" and only rated to about 100mA - the LK201 was said to draw over 1A and could cause telephone cables to overheat and/or melt.. It may only be 5V but there are 1 - 2A available (USB is only 0.5A) - so do check the cable rating if you are using a real DEC keyboard - or even a replacement and telephone cable...
Many telephone cables are "tinsel cable" and only rated to about 100mA - the LK201 was said to draw over 1A and could cause telephone cables to overheat and/or melt.. It may only be 5V but there are 1 - 2A available (USB is only 0.5A) - so do check the cable rating if you are using a real DEC keyboard - or even a replacement and telephone cable...
sorry i'm late but for future readers/reference, i did actually summarize the adapter process a few months ago when i had the same problem after buying a DECmate II: https://wiki.syspro.gs/#DEC/PDP8/DECmate_II_VR201_cable_replacement.md
the OSSC is entirely optional, but if you're into retrogaming they're worth having! i suspect you can use the same instructions to adapt for a VR241 color display as well, but i haven't tried because i don't have a machine capable of outputting color. i do have a rainbow 100, but my mother is kindly holding onto it for me while i work on moving back home so i can't play with it just yet
the OSSC is entirely optional, but if you're into retrogaming they're worth having! i suspect you can use the same instructions to adapt for a VR241 color display as well, but i haven't tried because i don't have a machine capable of outputting color. i do have a rainbow 100, but my mother is kindly holding onto it for me while i work on moving back home so i can't play with it just yet
Last edited:
VERAULT
Veteran Member
Scan converters. BAH. I never understood thier appeal when thier are so many good CRTS still out there.