Consider yourself lucky -- when I hit this issue about this time last year
(maybe it's seasonal?) I got excoriated off-list by a particularly irate
listmember for not having the foresight to just try reversing the cable
before asking on the list... :)
- Josh
On Tue, Mar 29, 2016 at 6:13 AM, Camiel Vanderhoeven <iamcamiel at gmail.com>
wrote:
  It's done on purpose, sort of an initiation rite.
All traces of this
 conversation will be wiped out so future /34 owners won't miss out on this!
 ;-)
 Camiel.
 -----Original Message-----
 From: cctalk [mailto:cctalk-bounces at 
classiccmp.org] On Behalf Of J?rg
 Hoppe
 Sent: dinsdag 29 maart 2016 13:28
 To: General Discussion: On-Topic and Off-Topic Posts <
 cctalk at classiccmp.org>
 Subject: Re: PDP-11/04-34 Programmer's Console manual error
 Noel,
 this is something every '34 owner must go through. Welcome to the club ;-)
 Joerg
 Am 29.03.2016 um 13:19 schrieb Noel Chiappa:
  So, something I just found out the hard way,
while debugging another
 'situation' with a PDP-11/04:
 The KY11-LB Programmer's Console maintainence manual contains a major
 error, in describing the configuration of the 20-conductor flat cable
 that connectors the front panel and the UNIBUS interface module
 (M7859). This is covered in Chapter 9, "Installation", which includes two
 figures, Figures 9-4 and 9-5.
 Those figures show the 20-conductor flat cable with the red edge
 stripe toward the outer edge of the front panel PCB (correct), and
 also toward the outer edge of the M7859 (WRONG). On the M7859, the red
 stripe edge needs to be oriented _away_ from the outer edge of the board.
 If it is plugged in as shown in these figures, the machine will not 
 operate:
  the four 'RUN/SR DISP/BUS ERR/MAINT'
lights will be on, but nothing
 else, and it will not respond to any keys. Fortunately, plugging the
 cable in reversed does not damage anything; simply reverse the cable.
       Noel