30 Nov
2005
30 Nov
'05
4:18 p.m.
Subject: Re: PDP-11/73 booting!
From: David Betz <dbetz at xlisper.mv.com>
Date: Wed, 30 Nov 2005 18:53:32 -0500
To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at
classiccmp.org>
Well, I have bad news and good news. The bad news is that I was
unable to fix my RL01 cable. I tried a few approaches to reconnect
the pins I could see were disconnected and wasn't able to get it to
work. However, the good news is that I was able to acquire another
cable and that fixed the problem entirely. In fact, the PDP-11/73
booted off the RL01 pack the first time I powered it up. I have three
packs and was able to read all of them. One contains RT-11 V5.5,
another is a TSX-Plus system disk but appears just to boot RT-11SJ.
It does have lots of files on it with ".tsx" extensions but doesn't
seem to boot TSX. The third is a blank scratch pack.
First, Congrats!
You need TSX.SAV and TSX also is built on RT11.
I'm now in the market for a cable and breakout
panel (cab kit?) for
my RQDX3 controller so that I can connect an ST225 drive and an RX50
floppy drive to my 11/73. I know it's possible to build one of these
but from my experience with attempting to fix the RL01 cable, I don't
think I want to tackle that project. If someone has a cable and
breakout panel they'd like to sell please get in touch with me.
There isn't a "cab kit" for RQDXn. The cables were all internal
and you used RQDXn in one of the BA23/123 boxen. So you either need
a M9058 from a scrapped BA123 or a mostly torn up BA23 (micro PDP11
or microvax) you can pull the pannel from. You also need the little
switch pannel inserts from the BA123 to enable READY/OFFLINE and
Writeprotect.
You need:
1 50 pin female to female IDC cable (max length 18") RQDXn to breakout
1 34pin female to female IDC cable (max length 30") (RX50)
1 26pin IDC to card edge (RDxx)
1 34 pin IDC to card edge (RDxx)
If your not using either of those boxes then your doing what I did
which was to build something DEC didn't document. The cables are
seriously are trivial and not a big a deal like those breakout boards
and the switch pannels.
Having done this I know.
Anyway, thanks to everyone who has given me help with
this machine. I
now have a working PDP-11/73 with 1.5mb of memory, an RX02 floppy
drive and an RL01 hard drive and it's all working!
Sounds like mine. ;)
Allison