test-drb May 2010

test-drb@ccmp.vtda.org

189 participants
248 discussions

[OT] Space Shuttle and ISS (was Re: Amiga 1000 helps winagainstpatent troll...)

by alhartman＠yahoo.com

I've always wanted to give Burt Rutan a run at a Space Shuttle replacement. I bet he'd do something really nice. His White Knight/Spaceship One combo seems pretty innovative. But, that's not intended to be a Shuttle replacement. Al

14 years, 7 months

Don't know if anyone cares, but...

by alhartman＠yahoo.com

My first PC was not a real IBM 5150/5160, it was a clone called the "American PC". It was a Taiwanese clone, and I got it from the company I worked for at the time which was an American Dealer. He was a bit unscrupulous as he would replace the BIOS it shipped with from Taiwan with home-blown IBM Bios chips. My system had 640k, was a "Turbo" system, and I replaced the 8088 with a V20. I still have the 8088 chip in my chip box. I also got it with two 360k drives, and two ST-213 drives which were 10mb versions of the ST-225. I even had a 2400bps Modem for it. It was in a case that looked like a 5150, but had a flip top like a car hood. It was a pretty nice system. I used it to run my BBS at the time, running TBBS software. It had a Clone CGA card that I attached to a Composite Zenith Green Screen display. I think this was circa 1983. I remember going to TCF and seeing the IBM 5150 Cassette units there for about $1000.00US. I really wanted one of those. I think I ended up paying about that for this one. I ended up selling it when I built a 286 system a few years later. I'm kinda sorry I did. It was a nice system for the time. I have a 5150 board built into a clone XT case right now. It only has 256k, so I need to configure one of the two RAM cards I have for it to bring it up to 640k. I put an 8bit OAK Video card in it that does MDA/MGA/CGA/EGA/VGA. So, I can use any monitor I can find on it. I do still have the PC style keyboard from that first system. I loved it so much, I couldn't part with it. Now, it will get use on this one. I found a 40mg Hard Drive on a card that I will use in the system. Al Keansburg, NJ

14 years, 7 months

Alignment Diskettes

by djg＠pdp8online.com

>Anyone have any pointers to places selling them, also may be looking for >3.5" alignment diskettes. > Try asking this person. I got 8" and 5.25" from him. Looks like he's only listing 8" right now but check with him. The 5.25" he wasn't listing but dug some up when I asked about them. http://shop.ebay.com/calcor4/m.html?_trkparms=65%253A15%257C66%253A2%257C39…

14 years, 7 months

Digital VIVACE

by quapla＠xs4all.nl

Hello All, Anybody familiar with an old DEC product called 'VIVACE'? It looks like it is a package for Win 3.11. Thanks, Ed -- Dit is een HTML vrije email / This is an HTML free email.

14 years, 7 months

San Fransisco area help needed

by h.j.stegeman＠hccnet.nl

Hi, Can someone in the SF area tell me if the Bethlehem-Steel-Administration-Building located at Northeast corner of 20th and Illinois still exists ? If it still there, is someone willing to check out if this IBM 3741 is still standing there. See: http://www.flickr.com/search/?q=ibm&w=55599586%40N00 It would be really great if someone can salvage its keyboard to repair my broken IBM 3741. Many thanks ! Regards Henk http://www.ibmsystem3.nl ============================================================================ ============================ Wanted: IBM 3741/3742 keyboard. Henk Stegeman h.j.stegeman at hccnet.nl Sat Apr 11 13:12:26 CDT 2009 * Previous message: (was) I [don't] hate E-Bay (was ...) Annoying bidding from buyer's perspective * Next message: HP262x keyboard to HP120 interface * Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] Hello all, Does anyone have a keyboard of an IBM 3741 or 3742 spare ? Mine has stopped working. IBM has used two custom LSI chip in this keyboard and makes it now non repairable :-( Please contact me off list if you can help. Thanks Henk http://www.ibmsystem3.nl * Previous message: (was) I [don't] hate E-Bay (was ...) Annoying bidding from buyer's perspective * Next message: HP262x keyboard to HP120 interface * Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] More information about the cctalk mailing list

14 years, 7 months

cctech Digest, Vol 81, Issue 20

by les＠frii.com

If the 100w bulb is not brighter than the 40w bulb, why would they make 100w bulbs? Just to waste energy? I realize that watts is not a measure of brightness, but for any given technology, the higher wattage bulb is brighter. >> >> But most people will, without thinking, say "Oh, a 100W bulb is >> brighter than a 40W, so the answer is obvious." And wrong.

14 years, 7 months

memory emulators, eprom programmers, embedded, etc.

by rdawson16＠hotmail.com

Hi, I querry all the sages out there for your recommendations for a romulator and burner set of tools. What I would like to have is a emulator tool like a USB device and a set of socket adapters (DIP and J lead for network cards); Some command line tools or open source that would let me pipe the result of a comple and link within a IDE, like eclipse (OK emacs if I must) for the compile debug test cycle; Then hardware to actually later blow (flash?) some parts, these would be 28 pin dips for my old z80 fun, and I would like to explore the boot ROM on a network card, so thats why I ask for a j lead socket adapter. Somebody brought up the B&C Microsystems guys a few pages back; I knew those guys. I think I was their largest customer; we bought hundreds of their programmers to ship with our product, a z-80 industrial terminal for PLCs. It was a build or buy decision; we went buy, as they gave them to us for $75 or so in volume. We had a few bugs, like buffer overrun and incorrect handshake over rs232, but they fixed it pretty quick. Nice guys. While I'm on the embedded topic, has anyone herd of this trick, their calling a 'glitching environment', wherein the fuse protected ROM of a CPU is made available, by bouncing the supply pin under DAC control and monitoring the bus? >From what I understand, it puts the processor into an indeterminate state occasionally, and allows you to access the bus of a protected ROM in the CPU. Secure microcontrollers are apparently, not that secure. I was looking into homebuilt spectrum analyzers (I'm KF7CJW) and ran across this hack from a kiddies texting IM toy, its a GHz tuner, display and processor for >$20 http://ossmann.blogspot.com/2010/03/16-pocket-spectrum-analyzer.html Processor glitching is discussed as part of their JTAG reflash of this toy. Not that I actually had to come clean by revealing processor glitching as an innocent discovery on another topic; I've been looking for ways to pick locks most of my life. Randy _________________________________________________________________ Hotmail has tools for the New Busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:…

14 years, 7 months

RD53 Restoration

by robert.jarratt＠ntlworld.com

Yes "blipping" the coil with a 9V battery moves the heads. When the drive was powered on I also measured the voltage by attaching a probe to each end of the coil cable, in that case I measured about 1.3V only. So I am guessing the coil is OK. Next step is to swap the boards back again. Regards Rob > -----Original Message----- > From: cctalk-bounces at classiccmp.org [mailto:cctalk- > bounces at classiccmp.org] On Behalf Of Rob Jarratt > Sent: 16 May 2010 20:13 > To: 'General Discussion: On-Topic and Off-Topic Posts' > Subject: RE: RD53 Restoration > > Thanks, never thought of the obvious, will dig out a 9V battery and try > that. > > Thanks again. > > Regards > > Rob > > > -----Original Message----- > > From: cctalk-bounces at classiccmp.org [mailto:cctalk- > > bounces at classiccmp.org] On Behalf Of Tony Duell > > Sent: 16 May 2010 20:03 > > To: cctalk at classiccmp.org > > Subject: Re: RD53 Restoration > > > > > > > > Many thanks for the reply. I am not an electronics expert > > unfortunately, but > > > > Alas sometimes I forget that not everyone had a mis-sepnt > shildhood... > > > > > will look at your suggestions. One thing I did (perhaps wrongly) > was > > measure > > > the voltage with one probe connected to the casing, not to the > other > > pin on > > > > This problaby is not the right thing to do. The point is that you > need > > to > > be able to pass a crurrent through the positioner coil in either > > direction (one way will exert a force to move the heads towards the > > spindle, the other way will exert a force to move the heads away form > > the > > spindle). Now if you had one side of the coil grounded (same voltage > as > > the chassis) yoy would need power supplies of both polarities wrt > > ground > > to be able to do that. > > > > What is more commonly done is a circuit based on what is called a > 'full > > H > > driver. Basiecaly it means both sides of the load (the coil in this > > case) > > can be driven. If one side is pulled towards ground tand the otehr > side > > to, wayu, +12V, the heads moce one way. But if the first side is > taken > > to > > +12V and hte second side to ground they move the other way. > > > > If oyu measure the voltage wrt ground on one end of the coil you are, > > effectively, only testing half the circuit. There could still be a > > fault. > > > > > the cable. I will try across the two pins to see what that is like. > I > > don't > > > have a DC supply I can use to "blip" the coil, unless I can press > the > > PSU > > > > Sure you do. I bet you'd get some movement using a small battery. P > > > > > from my MicroVAX II into service for this? Is there a danger I > might > > pass > > > too much current and burn the coil? > > > > There is, which is why you 'blip' it. Actually, a battery is probably > > the > > safest, a primary (non-recharageable) 9V battery is not going to > supply > > enough current to do much damage. > > > > -tony

14 years, 7 months

MicroVAX/VAXstation 2000 Memory Problem

by david＠marmotking.com

I have a MicroVAX 2000 motherboard which boots fine unless I plug in a 4MB memory expansion card. I already tried the following: [1] Attempted to boot with a different 4MB card. Doesn't work. [2] Booted a different MicroVAX 2000 motherboard with the original memory card. Worked. So, it would seem that the problem isn't with the memory card, since the card appears to work on another machine and another machine's card doesn't work on this machine. However, the odd thing is that it worked just 5 minutes ago. I know, if something's going to fail it has to fail sometime. Is there anything I should be looking for? Jumpers I should wiggle or anything like that? I'm doing this with the motherboad just sitting on the desk connected to a power supply and console cable (a special cable with pins 7 and 8 shorted) to make it a MicroVAX 2000 console cable.

14 years, 7 months

RD53 Restoration

by ard＠p850ug1.demon.co.uk

> > Many thanks for the reply. I am not an electronics expert unfortunately, but Alas sometimes I forget that not everyone had a mis-sepnt shildhood... > will look at your suggestions. One thing I did (perhaps wrongly) was measure > the voltage with one probe connected to the casing, not to the other pin on This problaby is not the right thing to do. The point is that you need to be able to pass a crurrent through the positioner coil in either direction (one way will exert a force to move the heads towards the spindle, the other way will exert a force to move the heads away form the spindle). Now if you had one side of the coil grounded (same voltage as the chassis) yoy would need power supplies of both polarities wrt ground to be able to do that. What is more commonly done is a circuit based on what is called a 'full H driver. Basiecaly it means both sides of the load (the coil in this case) can be driven. If one side is pulled towards ground tand the otehr side to, wayu, +12V, the heads moce one way. But if the first side is taken to +12V and hte second side to ground they move the other way. If oyu measure the voltage wrt ground on one end of the coil you are, effectively, only testing half the circuit. There could still be a fault. > the cable. I will try across the two pins to see what that is like. I don't > have a DC supply I can use to "blip" the coil, unless I can press the PSU Sure you do. I bet you'd get some movement using a small battery. P > from my MicroVAX II into service for this? Is there a danger I might pass > too much current and burn the coil? There is, which is why you 'blip' it. Actually, a battery is probably the safest, a primary (non-recharageable) 9V battery is not going to supply enough current to do much damage. -tony

14 years, 7 months

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test-drb May 2010