test-drb

test-drb@ccmp.vtda.org

101090 discussions

DEC power connectors (UNIBUS PDP-11s, mostly)

by jnc＠mercury.lcs.mit.edu

> From: Bill Degnan > is this info on or will be on your wiki? Well, it's not 'mine', but yes, I will be posting it when I find time. Noel

8 years

HP-2116 front panel lamps

by cc＠informatik.uni-stuttgart.de

Hi, I need to replace several broken lamps from our HP-2116B front panel. The old/original ones are CM-345 or OL-345. This makes sense, they are rated 6V 40mA 10000 hours. BUT: The maintenance manual says something different and is even wrong and inconsistent. HP part number is 2140-0035, description "Lamp, Incadescent, 6.3V, 0.75A" This can't be true. 92*0.75A would be 400W alone for the front panel lights... The manufacturer code is 71744 (Chicago Miniature Lamp Works), mfg part number 1775. That is indeed a 6.3V lamp, but 0.075A (better!). Problem: that is a midget _screw_ base lamp, so wrong socket and only rated for 1000h. The panel and switches need a midget flanged base lamp. Who wrote that manual? Was he drunk? ;-) Christian

8 years, 1 month

PDP-11/23 with RL02 on - eBay US

by u.tagge＠gmx.de

Just spotted this auction on eBay US Item: 263824036905 Location is: Glenview, Illinois Not cheap, but the seller is open for offers. Not affiliated with the seller.

8 years, 1 month

Scanned a few DEC manuals.

by mattislind＠gmail.com

http://storage.datormuseum.se/u/96935524/Datormusuem/DEC-MS11-HMSB-D_PDP11_… The MS11 main manual above seems to be a later version than the one already available http://storage.datormuseum.se/u/96935524/Datormusuem/DEC-11-H40SA-A-D_PDP-1… Earlier version then the one I found on bitsavers. http://storage.datormuseum.se/u/96935524/Datormusuem/DEC-11-HRJSA-B-D_RJS04… Didn't find much at all mentioning RJS04/03.

8 years, 1 month

by alemoco4＠gmail.com

Hi Are you still looking to purchase STC executel, I have just found my old one in the cupboard under my bed and could sell. Please email me if interested Regards Peter Sent from my iPhone

8 years, 1 month

Strange third party board in PDP-11/45

by jnc＠mercury.lcs.mit.edu

> From: Mattis Lind > I will take a picture of the boards in more detail so we can figure out > what they are doing later on. Thanks, that would be really useful. > My understanding is that slot 1AB and slot 26 AB is tied to each > other. So if there would be no expansion unibus there should be a M930 > in each of these slots. The same goes for slots 27AB and 28AB. Right, that's my understanding too. There's a diagram in the "PDP-11/45 Maintenance Reference Manual" (October, '73 edition, on pg. 60 - pg. 66 of the PDF), which gives: - slot 1 - UNIBUS A termination - slot 26 - UNIBUS A cable - slot 27 - UNIBUS B cable - slot 28 - UNIBUS B termination and my read is that the slot 26 cable is 'out to any UNIBUS memory, etc', while the slot 27 cable is 'in from the other machine in the dual-processor system'. (There's an interesting discussion in, IIRC, an RH11-AB - the dual-UNIBUS controller for the MASSBUS - tutorial manual which talks about the M9300, which is a terminator which can produce an NPG in response to an NPR; that is used when people want to attach the RH11-AB's second UNIBUS to the UNIBUS B, when there's no CPU on it. So the M9300 would go in slot 27, and the cable out to the RH11 in slot 28.) > I cannot see how a device in slot 26AB or 27AB would be able to > intercept MSYN here. Not _in_ slot 26 or 27, it's in the cable _between_ them! :-) Look at the common case, where UNIBUS A and B are connected: MSYN comes out of the CPU in slot 26, is jumpered across to slot 27 by the M9200, is carried across the backplane to slot 28, and then out (on either a BC11 or an M920). That dual-card thingy that comes with the Cache/45 would allow (if my surmise about what's going on is correct :-) the Cache/45 to place itself _between_ the MYSN out of the CPU (in slot 26) and the 'MSYN out to the rest of the system' (in slot 27). That does mean no separate UNIBUS A and B. But if my supposition as to how the Cache/45 works (that it fills itself by snooping on UNIBUS B in the MS11 controller slot) is correct, UNIBUS A and B would have to be connected together _anyway_, for that to work. (I _can_ imagine how to do it all without joining the two UNIBI together, but I will skip that for now.) Noel

8 years, 1 month

Strange third party board in PDP-11/45

by jnc＠mercury.lcs.mit.edu

> From: Mattis Lind > Here is how it is connected: Thanks for that - very informative! > The sandwiched dual boards are sitting in 27 / 26 AB. The board in 27AB > was empty (quick glance), while the board in 26AB has a few TTL chips > on it. Slot 26AB is the Unibus A slot, Slot 27 AB should be a > terminator on Unibus B. I'm more interested in _what_ the two boards are doing! :-) It seems they must be jumpering UNIBUS A and UNIBUS B together. (Which I didn't expect, but maybe... will have to ponder.) As to what _else_ it is doing, and why it has the cable to the main card... I think that it must intercept MSYN from the processor and only let it pass if there's no hit in the cache. (To explain why it would need to do that... normally with the MS11, there's a static partitioning between FastBus memory and UNIBUS A memory. So when the CPU goes to do a memory cycle, it can put the address out on both the UNIBUS and FastBus, with the certainty that it will only get a reply on one. But with the cache, if there's a hit, it would in theory get a reply on both, which might confuse it. Or if it takes the cache copy, and terminates the UNIBUS cycle, that might confuse the memory.) Or maybe I'm confused, because now that I think about it, UNIBUS A goes straight from the CPU to the UNIBUS A out slot, so the Able board couldn't intercept MSYN? I guess I need to understand the fine details of the UNIBUS A and B stuff, maybe it will make sense at that point. Oh, wait a moment: slot 26 is UNIBUS A out, slot 27 is 'UNIBUS B in', and slot 28 is UNIBUS B 'termination'. (27 is 'in' because when the M9200 is installed in 26/27 to join the two UNIBI together, obviously one has to connect an 'out' to an 'in'... and then 28 is not 'UNIBUS B termination', it's 'UNIBUS out' to the rest of the system. OK, so that works - MSYN coming out of slot 26 is intercepted by the dual double-card, and is only allowed to pass on cache miss. Yeah, that sounds like it should work. > The hex ABLE/ ACT board sits in slot 21 which is the memory controller > board for the MS11. One of two; the other is slot 16. > From: Paul Birkel > I wonder whether this CACHE/45 can coexist with MS11 memory on the > Fastbus itself According to that marketing thing you found, "User may optimize hit ratio by upper/lower limit switch settings", so one would have to configure the Cache/45 to not cache the block that the 'other' MS11 controller thinks it owns... otherwise both might respond to requests for addresses in that range.... :-) Noel

8 years, 1 month

Anyone in Europe with a North* Horizon or Advantage in working condition

by dkelvey＠hotmail.com

Hi I'm trying to assist Jeff with HxC to create a Gotek that can work with the North* hard sectored disk. It has been problematic because of timing constraints. Jeff has been working with several in the US but it is difficult to see what factors are important, working remotely. Jeff is in Paris, France. It would be great if he could get hands on access to one of these machines for a month or so, that was operational. Dwight

8 years, 1 month

Printerworks?

by cisin＠xenosoft.com

Has printerworks gone under? Their website is unresponsive. Does anybody have scans of their CX and SX "catalogs"? -- Grumpy Ol' Fred cisin at xenosoft.com

8 years, 1 month

RK05 spindle pulleys - trade 50Hz vs 60Hz?

by mattislind＠gmail.com

Hello! I have two RK05J-AA as part of a system that I guess has been imported used form the US. A DC-10 simulator. The only difference is the pulley, the motor position and a 230 / 115 V jumper inside. Is there anyone in 60Hz land that has the opposite problem and want to trade two spindle pulleys? The good thing for me that I would guess that it possible to use a lathe to get the diameter down to the correct 50Hz diameter. On the other hand going >from 50Hz to 60 Hz is tougher... Then there is a PC05 that has the wrong number of grooves on the motor pulley. Apparently it should be 16 instead of 20. Now in 50Hz land the only difference is that the punch would be slower than it should be. Using a 50Hz punch in 60Hz area might get you into problems, so maybe there is someone here as well that want to do a trade? /Mattis

8 years, 1 month

Jump to page:

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb