Video #3: Restored DEC PDP-11/23, 1983-1988. The purpose of this system was software development running under RT-11, for example: DCJ-11 based Single Board Computer, see my video #1. It is a very special, rare and unique design based on a Q_BUS/CTI-BUS converter. A lucky change was the reason to get a RD50,= 5Myte hard disk with attached controller board. I designed this Bus-Converter, wrote the the boot code, the format und (scope-loop) test programs and at least a RT-11 device driver. ( RH.MAC ). I was very surprised that my design as well the RD50 hard disk is still running without any problems after more than 20 years. The only big problem I got was the power supply with only 20 min uptime. I was able to replace via a standard PC 350W power supply ... but with a lot of barriers. All details, you will find in the video. The only remaining problem is the RX02 environment. I think, the problem is most likely related to these more than 20 years old floppy media. On the other site, I always get Hard Errors reflecting to a broken floppy drive or a faulty logic. Read operation works fine but any write operation results in a unusable Floppy media .I only have 5 remaining RX02 floppy media. Can anyone help me? I need one good RX02 media to verify where the problem comes from. Please contact me: Reinhard.Heuberger@gmx.de
PDP-11/23
DEC
Q-Bus
CTI-BUS
RT-11
RX02
RD50
historical
vintage
Computer
Reinhard
Heuberger
