test-drb December 2001

test-drb@ccmp.vtda.org

243 participants
1096 discussions

by dhquebbeman＠theestopinalgroup.com

> Rebuild a system the customer is satisfied with? Risk his > process again? Rather not. A special place in Hell awaits those unwilling to take risks... -dq

23 years, 11 months

Flashing Light Indicators un Simple Front Panels

by pete＠dunnington.u-net.com

On Dec 14, 16:16, Douglas Quebbeman wrote: > In particular, do any of you have familiarity with > systems that flash the on or power light as an > indicattor, sopecifiecally, of a power supply > problem? The only thing I can think of that's *designed* to do something like that is an SGI Indy; if you power one up and it can't even run the the code in the PROM, it flashes the power light (which is a two-colour LED). The usual cause id that there's no (recognisable) RAM at all in it. Probably not relevant to a PR1ME. Even less relevant, but in the same vein, is an Acorn Archimedes. If it can't boot, and can't set up the display, it flashes a 4-bit fault code on the floppy access LED. However, the code is RISC OS-specific. > Would anyone venture what a 2 Hz flash rate on the ON > LED of a Prime might mean? If it's a short "on" and a long "off", it might be a power supply that is starting up , detecting a problem, and shutting off again. And retrying, and ... Is there any accompanying, possibly fairly quiet, whistle/buzz/click that occurs at the same rate? -- Pete Peter Turnbull Network Manager University of York

23 years, 11 months

MITS 2SIO serial chip?

by ajp166＠bellatlantic.net

-----Original Message----- From: Ben Franchuk <bfranchuk(a)jetnet.ab.ca> >> Sure its trivial to do now but we were talking 1981 when PALS were >> expensive. Yes, they were compared to random logic, but if board space was costly they were cheaper. >I never heard about pal's until about 1990. In some ways the peripheral PALS are 1970s technology, really old to some of us. >chips are in a really sorry shape. You have vintage slow I/O (2 MHZ?) >or PC motherboard chip sets. Nothing in between. On my FPGA I can run >with a 250 ns memory cycle, but need to stretch it to 625 ns for I/O. Actually thats not true. BY 1981 you have peripherals in the 125ns read write timing range. Then again Z80 at that time was just hinting at 6mhz so z80 peripherals were of an according spped for that cpu. However, other parts were faster and often far cheaper. Personally if I wanted the SIO functionality for a NON-z80 system I'd never use the zilog part. Reason it was not cheap,nor was it easy to use for non-z80 systems. They were designed for the Z80, period. Unfortunatly they were slow. If you wanted faster the 83xx or 85xx parts from Zilog were a far better choice but Zbus was scary to most people and they weren't cheap. The other part of this is NEC and Intel did the MPSC (NEC D7201, INtel 8274) which was functionally identical to the SIO and was "tuned" for 8080/8085/8088/8086 style busses and faster as well. It was a more generic part than the SIO. Also around that time Signetics and friends were doing the 2681 part that was cheap and available in various flavors. Peripherals back then were quite varied. Allison

23 years, 11 months

Plastic latches for the Osborne?

by gibbsjj＠u.washington.edu

Hi all, Has anyone out there found a replacement for the plastic latches on the Osborne 1? I just got this machine, and one of them is broken off. What a bad design... considering how solid the rest of the machine is I am surprised they did not put some big hinged metal suitcase latches on the sucker! Thanks. Josh gibbsjj(a)u.washington.edu

23 years, 11 months

Apple DuoDisk (was Re: Stacking Apple ][ stuff)

by erd_6502＠yahoo.com

--- SUPRDAVE(a)aol.com wrote: > In a message dated 11/8/2001 5:06:19 AM Central Standard Time, > foo(a)siconic.com writes: > I do remember reading something of a faulty/out of spec component > inside the duodisk that would cause some issues with the floppy drives > but like I said, coming up 404 on it. Think I'll ask in comp.sys..... > and find out for sure. I'd like to hear more about this. I always used individual drives (typically SA400 mechs) when I did Apple development. The IIe and DuoDisk were too new and expensive for a low-budget shop like us (but we did eventually support the //c _and_ the Apple mouse) I have a DuoDisk but no cable. What pins were used? I think I _might_ have a cable that was sacrificed to the Amiga gods by having one of the pins broken out of one end for use as a modem cable (since the Amiga puts voltage on some of the pins). It was a stupid thing to do, but it was more than 10 years ago when Apple stuff was underappreciated. Anyone have an Apple part number for a DuoDisk cable? Will a 25-pin straight-through work? -ethan __________________________________________________ Do You Yahoo!? Send your FREE holiday greetings online! http://greetings.yahoo.com

23 years, 11 months

VS4000 hardware questions

by IVIE＠cc.usu.edu

> Well, I made room on my bench, opened up my grubby, new-to-me 4000/60, > and it only has one of the two RZ24 drives my partner paid for. I've > fired off email to the vendor asking him to ship the drive and mounting > hardware, but I don't expect that he'll have either. Take a closer look. Two drives can be attached to the plastic clip in the front middle of the machine, on on top and one underneath. Roger Ivie ivie(a)cc.usu.edu

23 years, 11 months

Hardest to Find Classic Computers (Was: RE: Way OT: Just say no t o squirrels & Pascal question)

by dhquebbeman＠theestopinalgroup.com

> When OT threads die and then get resurrected under even > wilder topics, its just not worth it. Ok, we've had threads similar to this one before, but maybe not quite... What are the hardest to find Classic Computers? What should not be counted: Systems that never went beyond prototype Systems that they made only one of Systems that were custom-designed for a single customer and were only in limited production Systems that were not "general purpose" computers Also not intended as the thrust of the topic: Systems you most of all want Rather, the systems I'me talking about would have been commercially produced, were general-purpose systems, made in quantity of say at least a baker's dozen. These systems might be generally available, and might go for a price you can afford, but you just can't *find* them where you're at. Around here for me, it would be PDP-8's and Lisa's. ??? -dq

23 years, 11 months

What 's a 3Com 3c515 worth these days?

by jhellige＠earthlink.net

>Well... I have no personal need for an ISA 10/100 in a WinTel box - I >have a 10BaseT network with 10Base2 and 10BaseFL branches going into >a port on my 10/100 switch. For old stuff, 10mbps is fine. If I were >going to buy this at all, I'd see about using it with AmigaDOS (and >working with Holger Kruse on an MNI driver, if he's still around) Holger isn't working on Miami any longer is he? I registered it a number of years ago but from the looks of it, it appears that development on it has stopped. I'm currently using an X-Surf with the MNI driver with the standard version of Miami (registered) on my A3000. Jeff

23 years, 11 months

Mike Stein

by mhstein＠usa.net

Sorry; trouble getting into ISP & mailbox filled up. OK now, c u off-list. m ---------------Original Message-------------- From: "Ernest" <ernestls(a)attbi.com> Subject: Mike Stein Hey, Mike. I've been trying to get ahold of you via email about your Apple II clone but your mail keeps bouncing back. Please contact me if you are still interested in selling those systems to me. Thanks. Ernest

23 years, 11 months

have a Happy ...

by oliv555＠arrl.net

>from Houston, wishing all list members a safe and happy holiday :) -nick o

23 years, 11 months

HP 1000/E

by steven_j_robertson＠hotmail.com

First, I'd like to say thanks to everyone that has provided help. The insight provided by this group is invaluable in getting a system like this going :-) I did a quick inventory of the cards in the rear of the machine plus a second 1000 carcass that I have and this is what I found: * (2) Time base generator * (3) Microcircuit A-2222 / 12566-60032 cards * (1) 55613 GMR-1 - I have no idea what this is. * (1) HS Terminal - 12531-80025 * (1) INTF - 1337 * (3) Natel 2101 R/D Converter I understand the "Time Generator" card but, really don't know the functions of the other cards. I know some of this info may be on the spies/~AEK site but, haven't had time to filter through those docs. The machine also has: * (1) 64K HSM 12747H - High speed memory * (1) MEM CONTR 2102B * (1) M.E.M 12731 I'm assuming these are just extended memory cards and controllers. At this point, the HP basic route certainly seems like the most doable. I did see those images on Jeff's site but, was pretty clueless as to how to get the data into the machine. Bob: exactly what is involved in your "Paper Tape Emulator". From the functional description, it doesn't sound all that complicated. This may be something, I could hack together. As a side note: I know where there are two more 1000/E that I could get for about $200 each. While I haven't inventoried them, each of those systems is a FULL rack of goodies including disk drives, X/Y data monitors, A/D converters, etc... One of the systems has a combo tape/hard drive and could possibly still have the OS installed. The other one has dual 8" floppies. I'm running out of room for rack sized systems but, those probably deserve a good home (mine). Happy holidays to all, SteveRob >From: Bob Shannon <bshannon(a)tiac.net> >Reply-To: classiccmp(a)classiccmp.org >To: classiccmp(a)classiccmp.org >Subject: Re: HP 1000/E >Date: Sun, 23 Dec 2001 09:56:42 -0500 > >Wow, you got an amazing deal! > >I've been looking for a spare 2113 for a while now, as I have a custom >instrument that is based on a HP 2113 processor. I would have easily paid >10 >times that price! > >As for operating systems and software, you have at least two options... > >First, the easy path... > >Simply run HP's stand-alone basic. You can download a binary image of the >media, originally a paper tape, from Jeff's HP2100 Archives. Now you need >a way >to get >that data into the machine, and a console port. > >You will also need a 'Buffered TTY Register' board to serve as a console >serial >port. Later HP machines (like the 2113) often use the BACI (Buffered Async >Communications Adapter) board, which is NOT compatible with HP Basic. > >Depending on what interface boards you have, we may be able to work out a >deal. > >I usually boot HP Basic from a custom tape reader emulator that holds the >binary >image of the paper tape in EPROM. This reader-emulator connects to a HP >'Microcircuit Interface' board, and the software is loaded using the >built-in >boot loader ROMs in the HP 2113. You simply power up, set a few switches >on the >front panel, then press IBL, Preset, then IBL once again, and the loader >code is >stored in memory. Pressing RUN at this point will load the tape image into >memory, and away you go. > >Now then the hard way... > >HP's operating system's for these machines are pretty nasty. The 'top of >the >line' OS was RTE-6VM, and the more common OS was RTE-IVB (RTE 4B). These >operating systems were unlike anything I've ever seen, cryptic, obtuse, and >fairly painful to use. As an example, to run a compiled program, you had >to >link the code into the OS itself. > >The hardest part here, is getting a useable disk system. RTE-IVB uses what >were >called MAC interface disks, while RTE-6VM also supported ICD drives, using >a >specialized version of the IEEE-488 interface. > >Supporting the original operating systems is a lot of work, and I strongly >reccomend you run HP Basic. > >Now, what exactly do you have? > >The HP 2113 was one of the last machines in a long series going back to >1968. >Your 2113 is binary code compatible with the original HP 2116, the first HP >product to use the then new-fangeled IC chips. HP2113's were still selling >for >$13,000+ in 1983, and are exceptionally well-built. > >It has no stack, but executes subroutines much like a PDP-8. In addition >to the >original HP 2116 instructions, the HP 2113 also adds several new registers >and >instructions, as well as a virtual memory scheme that can address 1 >megaword of >solid-state memory. > >Oh yes, many of the original interface boards from a 1968 HP 2116 will plug >right into your 2113 and work perfectly (but not the cool oscilloscope >point-plot display board...). > >I have a MS-DOS based version of the HP assembler, so you can assemble >small >programs on your PC. I am also working on a program for the PC that will >send >the paper tape image from the assembler into the HP via my tape reader >emulator. Once this is working, it should be possible to boot the HP >directly >from a file on the PC's disk. > >Take a careful inventory of the interface boards you have, and we can see >if >there is something in there you can use to get your machine running HP >Basic. >(many generic HP interface boards can be made to serve as psudo-tape reader >interfaces). _________________________________________________________________ Send and receive Hotmail on your mobile device: http://mobile.msn.com

23 years, 11 months

RS/6000, cheap to good home.

by doc＠mdrconsult.com

Well, most of one anyway. I have a 7011-250 upgraded from a 7011-220, which means that I replaced literally everything but the case. So I have the 220 entire, if you want to mount it on something. This includes PSU, system board, MCA riser, 8-bit color adapter & riser, floppy drive & cable, and the lock barrel & key. A standard >2G scsi disk & cable will work. I've heard that the graphics adapter is not supported past AIX v3.25, but I promise you don't want to run X on this dog anyway. Or you could use a standard MCA graphics adapter. I need an internal SCSI cable for my VS3100 m38, a memory expansion board for the PS/2 8570, and a GXT130P graphics adapter. I'd consider Q-Bus drive controllers for the VS-II I may or may not be rebuilding, depending on whether the trade for CPU & RAM goes through. If you have something that's worth more than the RS/6000 pieces/parts, let me know what else you need. I'm suffering no delusions concerning the value of an orphaned 7011-220. Doc

23 years, 11 months

MITS 2SIO serial chip?

by ajp166＠bellatlantic.net

From: Ben Franchuk <bfranchuk(a)jetnet.ab.ca> >Since I have no way of having a chip of 80's technology made I have to >limit the design to what looks realistic for that era. I dont get that? You want a 4mhz z80 or 5mhz 8085? Those are relatively common. Now, if your doing PDP-8 era then 1.2uS instruction cycle was the number, slow by todays standards. >This is what this is -- a hobby/ learning tool -- In the early 80s, I really was trying to do what zilog eventually did, make a Z280 more or less. That and figure out what this ucode thing was all about. >If it was $$$ making I would have to move to Seattle. :) Now that's depressing. ;)

23 years, 11 months

6502/Z80 speed comparison (was MITS 2SIO serial chip?)

by ajp166＠bellatlantic.net

Z80 uses it's time differently... Then again how many instuctions would it take to do a 16bit add (result in register or convenient place). The fact that both are still viable suggests they have adaquate speed and a rich enough instruction set to do many tasks. Last item, z80, Z180 and Z280 do not have the same timing. For example the Z280 can be run at a bus speed slower than the CPU speed and with the MMU and cache running in burst mode you get a very different bus utilization model. Generally the only things that count is: Can the cpu do the task? What cpu are you familiar with? What is the total cost to implement the task (firmware/software counts)? Politcial impacts (company prefers, owns, has, used before). Do I think z80 is better than 6502? Yes, I'm biased. Is 6502 a good cpu? I think so, it certainly beat the 6800 and a lot of others in the 8bit space. Would I design with it? No, lack of experience, no on hand software base for it, limited tools to work with it. Would I consider it, likely. I have 6502, 6800, 1802, SC/MP, SC/MPII, ti9900, 8048/9/874x, 8080, 8085, z80, Z180 Z280, 6809 and T-11 to pick from. For a new design (personal) of some size say to run an OS then Z280 or T-11 for single chip I have 8748, 8749 and 8751s around. For simple controllers 8085 is easy to use if it grows out of the 8749. Then again I also have upd78pg11s too. Allison -----Original Message----- From: Richard Erlacher <edick(a)idcomm.com> To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org> Date: Thursday, December 20, 2001 4:17 AM Subject: 6502/Z80 speed comparison (was MITS 2SIO serial chip?) >I've been on both sides of this question on a number of occasions and I've found >that the real challenge is to figure out what defines a level playing field for >such a comparison. I once concluded that running each processor at a rate >amenable with the same memory bandwidth was appropriate, but there are a number >of quesitons, still that have to be resolved. > >(1) the 6502 is designed in a way that lends itself very well to shared use of >its memory, i.e. using the memory for the CPU during phase-2 and letting a >memory-mapped video refresh circuit have it during phase-1. That's quite >reasonable and impacts the 6502 very little, but, if you try to do the same >thing with a Z80, you get tangled up with its variable cycle lengths pretty >quickly. > >(2) the Z80 demands a pretty short cycle for its instruction fetch (M1) cycle, >and, if that's to be the rate-determining step for the cmparison, i.e. if the >memory bandwidth requirement is determined on that basis, (no wait-states >allowed) then the 6502 will eat it alive. That, of course, is because 50% of >its memory bandwidth will be frittered away due to the fact that the M1 cycle is >short and has a wasted tail end (refresh cycle) while the 6502 doesn't have that >burden. Further, if that determines the memory bandwidth, then the M1 cycle >(~400 ns with 200ns memory of the era) means that a 4 MHz CPU wouldn't be able >to run with it. > >Fairness might demand a wait state, but that would then raise the question of >what's the bus bandwidth at which the 6502 will be run (assume a 20 MHz 6502 and >a 20 MHz Z80, but use memory of their own era.) Also, the refresh cycle itself >is a mite short for what the CPU does at 4 MHz. How would one stretch it to >where it wouldn't impinge on the next memory cycle? If you have to share the >memory bus of the 6502, why not the Z80 as well? If you can use timing tricks, >why not on the 6502? I'd say use whatever timing tricks the two CPU's can live >with, but run them to their best advantage. Run phase-1 on the 65-2 for only 25 >ns, then switch to phase-2 for whatever time the Z80 uses the memory. Let the >Z80 use a wait or two in the M1, and stretch the refresh so the cycle can be >complete when the next cycle is in progress. Since non-M1 memory cycles are 3 >clock ticks, the clock could be pretty fast, couldn't it? > >(Can you see how this gets tangled up in technical problems of fair comparison? >That's BEFORE the question of what sort of benchmark software is to be used >comes up.) > >The shortest 6502 instructions take two clock ticks, but some overlap the next >instruction fetch. The shortest Z80 instructions take an M1 cycle, followed by >refresh, to fetch, and I'm not sure whether they execute during the refresh >(they're internal, so that's conceivable) or whether they produce an idle bus >cycle. I also don't know what happens during that idle bus cycle. Simply >sitting down and calculating the relative instruction timing might not be so >easy. It certainly won't be easy to get right. > >My own experience has been that in controller applications, manipulation of >16-bit values doesn't come up as often as I once believed. Mostly it seems the >values that are dealt with are 8 bits or fewer. Others may see this >differently, however. > >Dick > >----- Original Message ----- >From: "Greg Ewing" <greg(a)cosc.canterbury.ac.nz> >To: <classiccmp(a)classiccmp.org> >Sent: Wednesday, December 19, 2001 3:30 PM >Subject: Re: MITS 2SIO serial chip? > > >> Ben Franchuk <bfranchuk(a)jetnet.ab.ca>: >> >> > what is the faster CPU -- A 6502 or Z80 style processor like >> > the rabbit. >> >> Back when I used to spend long blissful evenings hand-assembling Z80 >> programs [1] I got the impression that Z80 code was more compact than >> 6502 code, being able to manipulate 16-bit values with single >> instructions in many cases. Whether it was actually faster I don't >> know, but I suspect it was, as long as you stuck to the 8080-like core >> instructions which didn't take ridiculous numbers of cycles to >> execute. >> >> [1] I didn't do it in a storage locker, although I did often >> had the heater on in winter. >> >> Greg Ewing, Computer Science Dept, +--------------------------------------+ >> University of Canterbury, | A citizen of NewZealandCorp, a | >> Christchurch, New Zealand | wholly-owned subsidiary of USA Inc. | >> greg(a)cosc.canterbury.ac.nz +--------------------------------------+ >> >> >

23 years, 11 months

FS/FT: DEC TZ85 DLT tape drive

by mrbill＠mrbill.net

I'm not sure how old this is, or if it meets the 10-year rule.. but I've got a DEC TZ85 (first-generation DLT; also reads TK50 and TK70 media) SCSI DLT drive for sale or trade. Ended up not being enough capacity (does 2.6G on a DLT-III tape) for what I needed at home. I've got the TZ85-A in original DEC big loud and noisy desktop 5.25" enclosure (has Centronics-style SCSI-I connectors, and I'll throw in the DEC scsi terminator). If it helps, I'll also throw in 10 or 20 DLT-III tapes, if you want to pay shipping (these tapes also work with all current DLT drives, at 10/20G capacity if I remember correctly). Looking to sell, or trade for ham radio or scanner (radio) gear. I'm in Austin, TX, and this beast is heavy (as are the tapes), so a local or nearby deal preferred, but if you're not local, buyer pays shipping. Email me if interested. Bill -- Bill Bradford mrbill(a)mrbill.net Austin, TX

23 years, 11 months

Fairchild FST-2?

by neil.macmillan＠freeuk.com

The Fairchild FST-2 computer was used to control a family of Semiconductor ( chip ) testers I guess from sometime in the mid 1970s to around the mid 1980s. The family of testers were branded as "Sentry", "Sentinel" and "Series10" ( maybe some others ). The FST-2 was a 24-bit machine with its memory interleaved between odd and even addreses. When the CPU was reading/writing to an odd address, a peripheral could address an even address and vice-versa using DMA. Early machines were booted from tape, but newer machines had a PROM boot board which allowed booting from 8" floppy, hard-disk, tape ( and possibly a network. ) Early machines had 25 bit wide memory with a parity bit, while the later machines had 30 bit wide memory which provided error detection and correction. Control of the tester was via two busses known as the long-register bus and the short-register bus. If you come across an FST-2 which can be powered up, set the console switches ( piano keys ) to 06760000 in octal and press STOP, RESET, LDP, LDC and START. The machine should waken up. There are a few stand-alone FST-2s kicking around without any tester hardware. These were used as a FACTOR compiler co-processor for a development system which was based on the HP1000. Most FST-2s will be part of a chip tester. If the chip tester is still working, the whole system is still quite valuable. Even as a source of spares. Although the tester has a lot of different power supplies the FST-2 probably ony needs 5.0V and the RS-232 voltages to get running. The FST-2 ran an OS named M3 ( "M Cubed" ) and was programmed using a FORTRAN-like language named FACTOR, ( Fairchild Algorithmic Compiler Tester ORiented. ) Most Sentry testers could test digital chips with 60 pins up to 10 MHz. Some later Sentrys could test up to 120 pins at 20 MHz. I remember FST-2s being very slow to compile FACTOR programs. Most users ended up compiling their program and test patterns ( Vectors/Truth-Tables ) on a VAX. Fairchild ( and later Schlumberger ) provided really good in-depth training and documentation for the CPU and the testers for hardware maintenance and programming. The manuals which were up for grabs were either manuals/schematics which were shipped with a tester, or training manuals which some engineer picked up in San Jose or Munich.

23 years, 11 months

Wanted DEC VT1200 mouse and cable

by mcguire＠neurotica.com

On December 24, Bill Pechter wrote: > The cable that goes between the DEC VT1200 (looks like an N connector) > and their monochrome video monitors like a vt262 and a DEC VSXXX-AA > mouse. > > I've got a working VT1200 minus mouse and video cable. > I was going to cobble one up with some RG6 and a BNC connector and > an N connector (if that's really an N connector) but I'd really rather > find the right cable and spend more time enjoying the toy rather than > fixing it. FYI, if that connector is about the size of a BNC but threaded, it's a TNC connector. -Dave -- Dave McGuire St. Petersburg, FL "Less talk. More synthohol." --Lt. Worf

23 years, 11 months

Fluke, GRID and Daisy

by kenziem＠sympatico.ca

It's funny how once you find out about a certain machine they then seem to show up everywhere. Found a Fluke 900* yesterday they are asking $25 (Cdn) for it, looked like it was missing attachments. Picked up a GRID 1500 laptop it came with 6 batteries, external 3.5, 5.25 and tape as well as a vga adapter. It's missing a battery charger, and when it boots mentions a config error. The Daisy was sitting in the back, they had it put with office furniture. It looks like a desk but with a closer look, there is a 8" floppy drive on the side and at the base all of the usual connectors.

23 years, 11 months

More... Re: VS4000 hardware questions

by LFessen106＠aol.com

In a message dated 12/24/01 6:51:52 PM Eastern Standard Time, doc(a)mdrconsult.com writes: > The "disconnect your terminal" part was the thing. I find it odd that > the box won't even finish power-up diags if the terminal is connected > and turned off. > > Doc > That's not so odd.. The exact same thing happens with my 3 vs3100m35's, my vs3500, all my Decstations and my Alphastation as well.. I just leave them completely headless for the most part, and the ones I need a head on always have a terminal connected and running.

23 years, 11 months

CD32 and CD-TV (was Re: Hardest to Find Classic Computers)

by rachael_＠gmx.net

on 19-Dec-01 18:53:47, Ethan Dicks wrote: >I still have mine that I bought new. I use it to play CD+G discs and >not much else. Wish I had the MPEG cart - got some VCDs that would >be fun to play on it. I have an SX-1 adapter that turns a CD32 into >sort of an A1200, but I haven't had the time to check it out and put >it together. Does anyone have any docs for that? The jumpers are >labelled, so there's not much guesswork, but any docs are more than >I have now. http://www.amiga-hardware.com/sx-1.html, there is a PDF version of the docs there. Regards Jacob Dahl Pind -- CBM, Amiga,Vintage hardware collector Email: Rachael_(a)gmx.net url: http://rachael.dyndns.org

23 years, 11 months

M8650 async board problem

by djg＠drs-esg.com

One more thing you might want to watch out for with excessive +5 voltage drop on an 8/E is the 5V fuse. I have mine almost full of cards and the fuse holder melted. I have a maintenance handbook (which I got after the failure) which said that this was a known problem. I measured the current draw and found it was slightly above the power supply rating so added another supply to power half the backplane.

23 years, 11 months

Apple II serial number 2000?

by pete＠dunnington.u-net.com

On Dec 24, 6:31, Ernest wrote: > > I have an Apple II, serial number 2000. There is some question as to whether > or not this acurate so I thought that I would toss it out here and see if > any of you can verify it one way or the other. [...] > One person told me that it is in fact, a revision 0 board, and the edge > connectors are unusual (?) but someone else (Sellam) mentioned that he > believed that Apple began the A2 series with serial number 2001 (a spin on > the 2001 movie.) I would like to hear if anyone has any thoughts or opinions > about it. It certainly looks like an early Rev.0 board -- it has the memory configuration blocks, the right kind of sockets, old DRAM, and no extra video pin in the corner. It's an old keyboard as well (look at the power light). It's amazingly clean. You must have taken a bit of care over it, from your description. A nice find, anyway. > The pictures will expand to 640x480 if you click on the main images. Not, alas, in Netscape. But right-clicking on them works. -- Pete Peter Turnbull Network Manager University of York

23 years, 11 months

720k floppy

by Golemancd＠aol.com

anyone know where i can find some 720k floppies thanks Joee

23 years, 11 months

I'm back!!!!

by vaxman＠earthlink.net

Bet y'all missed me :) Got the new Covad/Earthlink DSL hooked up finally... The firewall may actually be working too... Need to check it out... Anything of great import happen in the last two months (since 31-oct-01?) Laters, clint

23 years, 11 months

720k floppy thanks

by Golemancd＠aol.com

thanks for the info i am going to see if i can find some on ebay will try the hole covering thing also i have a couple of computers that use 720k tandy and a toshiba laptop thanks again Joee

23 years, 11 months

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test-drb December 2001