Re: HP & 800BPI / was Re: Tape cleaner on eBay

Brent Hilpert wore: >I had that problem with the stuck reel hubs. Failed to take my own advice-to-self to leave the reels unmounted and they stuck again, >although easier to get off this time as it hadn't been many years under pressure. I ended up covering the rubber hub with black electrical ta

Re: Q-bus I/O project

On Sat, Oct 10, 2015 at 11:38:45AM -0400, Paul Koning wrote: >Did you check the PHY latency for GigE? I know it's insanely large for >10G-BaseT, but I don't remember if GigE is still reasonable. I was worried about that, since other PHY data sheets list high-ish numbers (hundreds of nsec) as if t

Re: DEC H7140 (11/44) power supply revisions and general advice?

On Sat, Oct 10, 2015 at 8:44 PM, Josh Dersch wrote: > On Sat, Oct 10, 2015 at 2:38 PM, tony duell > wrote: > >> > >> > From a quick glance at the schematic I think that this part is related >> to >> > the fan driving circuitry. The diodes look like some kind of protection >> >> Yes. >> >> > diod

Re: DEC H7140 (11/44) power supply revisions and general advice?

On Sat, Oct 10, 2015 at 2:38 PM, tony duell wrote: > > > > From a quick glance at the schematic I think that this part is related to > > the fan driving circuitry. The diodes look like some kind of protection > > Yes. > > > diodes which is good to have when switching inductive loads. I have > re

Re: Dead PET4032

Hi Tony, On 05/10/2015 16:55, "tony duell" wrote: > And I would be surprised if you got nothing on the screen either. Odd bit > rot would mean the wrong patterns for some characters. But still something. The heater is working in the tube and now that I've got a proper DMM I'm getting the correc

Re: Q-bus I/O project

On 2015-10-10 2:10 PM, David Bridgham wrote: Wow. A pretty board indeed. Thanks for showing it off. This is also interesting to me since a friend and I have been talking about building something rather similar (and entirely different at the same time, we're just focusing on the mass storage f

Re: FS: Cray J932SE system

On Saturday (10/10/2015 at 02:51AM -0400), et...@757.org wrote: > > Long gone, but probably some of my favorite boxes were Papa Smurf > and Smurfette: > http://imgur.com/a/C2rGj > > (The big blue Challenge XLs) > > Other computers long gone in the pics as well, from the tinkering > over the year

RE: DEC H7140 (11/44) power supply revisions and general advice?

> > From a quick glance at the schematic I think that this part is related to > the fan driving circuitry. The diodes look like some kind of protection Yes. > diodes which is good to have when switching inductive loads. I have really > no idea why they have been removed. But I don't think it is

Q-bus I/O project

Wow. A pretty board indeed. Thanks for showing it off. This is also interesting to me since a friend and I have been talking about building something rather similar (and entirely different at the same time, we're just focusing on the mass storage function and using an FPGA). I'm curious about

Re: UNIBUS RAM with Parity vs. None

On Oct 10, 2015 12:27 PM, "Eric Smith" wrote: > > > Anyone disagree, and if so why did DEC want their 11/05 S to use "D" model > > core (D=parity) and not C (C=no parity)? The PDP 11/40 I have uses C. > > The H217D is the no-parity plane, and the H217C has parity. > > For the parity to do anythin

Re: FS: Cray J932SE system

That is quite an impressive pile of sgi. Do you have any of the big sgi gear around still? I have a bunch of the smaller workstations but have not managed to get any of the bigger desksides. On Sat, Oct 10, 2015 at 2:51 AM, wrote: > SYS_CRAYHOST="wopr" >> :-) >> -- >> Chris Elmquist >> > > :-)

Re: Symbolics MCD-405 tape drive / Georgens Industries

On 10/9/15 9:32 PM, Josh Dersch wrote: On 10/8/15 3:53 PM, Josh Dersch wrote: On Thu, Oct 8, 2015 at 11:15 AM, Al Kossow mailto:a...@bitsavers.org>> wrote: Does anyone have a loose 3M/Georgens MCD-405 tape drive they could take board pictures and firmware dumps from, or any of the

Re: DEC H7140 (11/40) power supply revisions and general advice?

lördag 10 oktober 2015 skrev Josh Dersch : > > > On Oct 10, 2015, at 4:15 AM, Mattis Lind > wrote: > > > > 2015-10-10 5:42 GMT+02:00 Josh Dersch > >: > > > >> Hey all -- > >> > >> > > First of all I haven't poked around in the PSU of my 11/44 since it > worked > > fin

Re: Computers in Election Vigils - take two

On 10/10/2015 10:44 AM, Paul Koning wrote: That's not the real problem. The real problem is that you had no way to be sure, no way to verify, that the machine was recording your vote and would accurately report it later. It might just as easily report numbers that someone had told it to re

Re: DEC H7140 (11/44) power supply revisions and general advice?

lördag 10 oktober 2015 skrev Josh Dersch : > > > On Oct 10, 2015, at 2:15 AM, tony duell > wrote: > > > >> > >> Once again, I find myself in over my head debugging a power supply, this > >> time an H7140 from a PDP-11/44. Here's the skinny: > > > > That doesn't surprise me, the H7140 is one of t

RE: DEC H7140 (11/40) power supply revisions and general advice?

If I remember correctly I had a problem in this area that turned out to be a loose/dry joint where the two thermistors that are across the relay joined together. In my case it was an intermittent fault though. Regards Rob > -Original Message- > From: cctalk [mailto:cctalk-boun...@class

Identification of IBM SMS backplanes

Found some IBM parts recently. Any idea what specifically these might have come out of? I'll be picking them up soon and getting more pictures, but here's a few for now. http://imgur.com/a/pikqG Thanks, Kyle

Re: UNIBUS RAM with Parity vs. None

> Anyone disagree, and if so why did DEC want their 11/05 S to use "D" model > core (D=parity) and not C (C=no parity)? The PDP 11/40 I have uses C. The H217D is the no-parity plane, and the H217C has parity. For the parity to do anything useful, you have to also have an M7259 module, and IIRC t

Re: DEC H7140 (11/40) power supply revisions and general advice?

> On Oct 10, 2015, at 4:15 AM, Mattis Lind wrote: > > 2015-10-10 5:42 GMT+02:00 Josh Dersch >: > >> Hey all -- >> >> > First of all I haven't poked around in the PSU of my 11/44 since it worked > fine when powered up. But the design of the H7140 is a lot similar to

Re: Computers in Election Vigils - take two

> On Oct 9, 2015, at 5:39 PM, Jecel Assumpcao Jr. wrote: > > John Robertson asked: >>> After the fiasco about the Deibold machines changing votes during the >>> Bush election of 2000, Brazil opted for them? > > To which Alexandre Souza replied: >>Yep. Welcome to the land of the stupid. >

Re: Q-bus I/O project

> On Oct 9, 2015, at 9:38 PM, John Wilson wrote: > > ... it's > supposed to be a Q-bus bridge that connects over Ethernet), but I wanted to > still be able to do something fun in the very likely case that the Ethernet > port doesn't work (no idea if my PCB layout is kosher for something as fast

Re: DEC H7140 (11/44) power supply revisions and general advice?

> On Oct 10, 2015, at 2:15 AM, tony duell wrote: > >> >> Once again, I find myself in over my head debugging a power supply, this >> time an H7140 from a PDP-11/44. Here's the skinny: > > That doesn't surprise me, the H7140 is one of the most complex PSUs you are > likely to come across... >

Re: DEC H7140 (11/40) power supply revisions and general advice?

2015-10-10 5:42 GMT+02:00 Josh Dersch : > Hey all -- > > First of all I haven't poked around in the PSU of my 11/44 since it worked fine when powered up. But the design of the H7140 is a lot similar to the design of the H7104, the PSU of the VAX-11/750 which I worked quite a lot with. http://www.d

Re: Q-bus I/O project

On Fri, 9 Oct 2015, John Wilson wrote: On Fri, Oct 09, 2015 at 09:48:18PM -0500, Jay Jaeger wrote: Do U17,U15,U10,U6 perhaps have some solder bridges, or is that just some flux hanging around? It's flux, but thanks for the heads-up! I went over everything with liquid-flux-soaked solder-wick

Re: Q-bus I/O project

On 2015-10-10 03:38, John Wilson wrote: This may never see the light of day (if the prototype turns out to be stillborn) but it's pretty and I can't resist posting a pic before I've powered it on and proven its uselessness: http://www.dbit.com/wilson/projects/qba.jpg Crazy amounts of p

RE: DEC H7140 (11/44) power supply revisions and general advice?

> > Once again, I find myself in over my head debugging a power supply, this > time an H7140 from a PDP-11/44. Here's the skinny: That doesn't surprise me, the H7140 is one of the most complex PSUs you are likely to come across... > When power is applied (plugged in, breaker switch flipped to "O

RE: WTT: My Amiga Mouse for your Atari ST Mouse!

They were switchable. There are some USB adaptors on Ebay... Dave G4UGM > -Original Message- > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Zane Healy > Sent: 10 October 2015 01:18 > To: General Discussion: On-Topic and Off-Topic Posts > > Subject: Re: WTT: My Amiga M