[cctalk] Re: Lunar Lander, bug

On 2024/06/17 12:26 p.m., Ethan Dicks via cctalk wrote: On Mon, Jun 17, 2024 at 1:53 PM Mike Katz via cctalk wrote: I remember running this program at school in the mid 1970's. This runs on 4K Focal '69 without the extended functions enabled. So it should run on a 4K PDP-8/L. ... It was

[cctalk] Re: IBM 360

On 2024/04/09 7:53 p.m., Murray McCullough via cctalk wrote: I had not realized the IBM 360 was 60 yrs. old this month. I worked on such a computer in the late 60s in Toronto. What one could do with 8 Kbytes of ram was remarkable! Happy computing Murray  One of my early summer jobs as a

[cctalk] Re: Double Density 3.5" Floppy Disks

On 2024/04/30 10:08 a.m., Anders Nelson via cctalk wrote: Having grown up with 1.44MB 3.5" floppies, I have a question: is it possible to use a 1.44MB disk and just format it as a 720K disk? =] -- Anders Nelson www.andersknelson.com As I recall you had to bulk erase the old diskette and then

[cctalk] Re: typical IC kits on Amazon and elsewhere

On 2024/03/30 7:53 p.m., Glen Slick via cctalk wrote: On Sat, Mar 30, 2024 at 5:11 PM Jonathan Chapman via cctalk wrote: Standard TTL 74XXX is drying up rather quickly. Futurlec still has some TTL but 7404s are all gone. Even LS is hard to find. Ours comes from Mouser, between two part #s

[cctalk] Re: FW: Re: ADM3a screen rot.

On 2024/01/29 12:45 p.m., William Sudbrink via cctalk wrote: Sellam Abraham wrote: I think you were fine. That's how you discharge them anyway. You were just missing the grounding wire :) Yes, I have one set up for just that purpose. Wire clamped to the shaft with an alligator at the

[cctalk] Re: Looking for 1970s OAK keyboard switches...

On 2024/01/25 6:28 a.m., Paul Koning wrote: On Jan 24, 2024, at 3:52 PM, John Robertson via cctalk wrote: I've been hunting for a while now for OAK PCB mount keyboard switches that I can't find a part number for. I've attached a product listing for the switch that shows it pretty well

[cctalk] Re: Looking for (WTB:) 1970s OAK keyboard switches...

On 2024/01/24 12:52 p.m., John Robertson via cctalk wrote: I've been hunting for a while now for OAK PCB mount keyboard switches that I can't find a part number for. I've attached a product listing for the switch that shows it pretty well. DPST-NO preferred. Only $0.40 in the early '70s! Any

[cctalk] Looking for 1970s OAK keyboard switches...

I've been hunting for a while now for OAK PCB mount keyboard switches that I can't find a part number for. I've attached a product listing for the switch that shows it pretty well. DPST-NO preferred. Only $0.40 in the early '70s! Any quantity considered... Thanks! John :-#)# --

[cctalk] Re: FYI: Hobbes OS/2 Archive logs off permanently in April

On 2024/01/10 10:56 a.m., Dennis Boone via cctalk wrote: > According to a warning on the site: "After many years of service, > hobbes.nmsu.edu will be decommissioned and will no longer be > available. You the user are responsible for downloading any of the > files found in this archive

[cctalk] Re: PDP 11/34 or 11/04 front panel question

On 2023/12/19 4:26 a.m., Tom Hunter via cctalk wrote: I just realised that I never followed up on this. After some research and a few phone calls to manufacturer support lines I settled on SikaBond SprayFix as the glue. ... The front panel has now been re-assembled and is fully functional and

[cctalk] Re: Free to good home HP 7510a Photo Plotter - UK

Location? On 2023/11/16 2:24 a.m., Dave Wade G4UGM via cctalk wrote: Folks, Trying to reduce the weight in my loft and I would like to donate my HP Photoplotter to a good home. . Photos of the plotter and some sample plots are on my OneDrive here:-

[cctalk] Re: ROM data for Lear Siegler ADM31?

Hi Peter, Thanks, I'll check with Ian if he tried those or not... John :-#)# On 2023/08/03 11:58 a.m., Peter Ekstrom wrote: Hi John, Would these be what you are looking for? https://bitsavers.org/pdf/learSiegler/ADM_31/firmware/ -Peter On Thu, Aug 3, 2023 at 2:47 PM John Robertson via

[cctalk] ROM data for Lear Siegler ADM31?

I sold my Lear Siegler ADM31 recently and the new owner (Ian) has found that one of the ROMs failed before he could archive it - or it was defective to start with. So my question to the list is - does anyone have the ROM codes (there are three of them) archived? I don't think Ian is a

[cctalk] Re: Don Lancaster has passed away at 83

On 2023/07/01 1:10 p.m., Sellam Abraham via cctalk wrote: Don Lancaster passed away on June 7. https://gilaherald.com/obituary-for-don-lancaster/ I hope his website is well preserved: https://tinaja.com/ Sellam web.archive.org has many copies archived:

[cctalk] Re: Recovering floppies attacked by mould

On 2023/05/25 5:11 p.m., Sellam Abraham via cctalk wrote: Tom, You may save yourself some time with this nifty contraption ==> https://www.ebay.com/itm/303620862566 It's a floppy disk cleaning apparatus. You place the floppy disk into the frame, apply your cleaning solution and cloth to the

[cctalk] Re: Schematics for Lear Siegler ADM31?

On 2023/04/23 3:16 p.m., Glen Slick via cctalk wrote: On Sun, Apr 23, 2023 at 3:10 PM John Robertson via cctalk wrote: Oh, I am missing two key caps for the ADM31, anyone have spares? Not sure what is printed on them at this point, but any caps would be better than missing ones to start

[cctalk] Re: Schematics for Lear Siegler ADM31?

On 2023/04/18 8:48 p.m., Tony Duell via cctalk wrote: On Wed, Apr 19, 2023 at 2:37 AM Tom Hunter via cctalk wrote: ... or four $20 power transistors to protect a 10 cent fuse like on the DEC VR-14 display. In general the transistor(s) will fail short-circuit, thus taking out the fuse too.

[cctalk] Re: flipchip cleaning and pin corrosion inhibition

On 2023/04/23 10:00 a.m., Paul Koning via cctalk wrote: On Apr 23, 2023, at 12:54 PM, Fritz Mueller via cctalk wrote: Hi folks, I’ve been picking my way through a PDP-8/L restoration lately. I’ve found that everything in the machine is covered with a uniform layer of dark “soot” (enough

[cctalk] Re: Schematics for Lear Siegler ADM31?

ly:* http://www.bitsavers.org/pdf/boschert/Boschert_OL25_Single-Stage_Power_Supply_Maintenance_Manual_May79.pdf and it was buried on bitsavers - where I went before bothering the list! Thanks folks! John :-#)# On Tue, Apr 18, 2023 at 12:20 AM John Robertson via cctalk < cctalk@classiccmp.org&g

[cctalk] Schematics for Lear Siegler ADM31?

I've checked bitsavers.org (Al does a great job!), and a number of forums, but no luck finding schematics for my ADM31 that I am trying to resurrect. The power supply has issues and I need to identify a blown out resistor - the switching supply is a Boschert model 1001 date code 7943 Revision

[cctalk] Re: HP9825A for sale

On 2023/04/17 9:12 a.m., Sellam Abraham via cctalk wrote: My initial reaction is that $2,000 seems a "bit" optimistic. That being said, I'm surprised to see (on eBay's Terapeak) a couple of these sold within the past year for around $1,100. Sellam One sold on eBay for $2492USD...Apr 6, 2023:

[cctalk] Re: Looking for EPROMs

On 2023/03/27 2:10 p.m., Mark Linimon via cctalk wrote: On 03/27/2023 5:38 PM GMT rescue via cctalk wrote: have a number of 2764, 27256, have some 27128 I think too Myself as well, probably down to 1702s. Right now with some current money trouble they are looking like assets :-/ mcl I'm

[cctalk] NOS Tapes 3 X 3M DC 600A 60MB Cartridges (1991)...(speaking of tapes)

Anyone interested in 3 tapes - has Olympics logo - still in original wrapping? Ether pick up at my shop or pay for postage and handling... John :-#)# -- John's Jukes Ltd. 7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 Call (604)872-5757 (Pinballs, Jukes, Video Games)

[cctalk] Re: Identifying a Failed Diode in a Rainbow H7842 Power Supply

On 2022/11/27 1:21 a.m., Rob Jarratt via cctalk wrote: I have done a little more probing around. I have found that the 7812 regulator that drives Vstart on sheet 1 of Tony Duell’s schematic is shorted, so I will have to replace this too. I have not found anything else that looks obviously

[cctalk] Re: Shipping help in Brunswick, GA

On 2022/11/06 8:37 p.m., John H. Reinhardt via cctalk wrote: So, I screwed up and in my excitement to find a DEC BA123 chassis (and MVII parts) I bid on an Ebay auction where there is no shipping and it's "Local Pickup Only".  The problem is that I'm near Fort Worth TX and the MVII/BA123 is in

[cctalk] Re: 7485 chip history??? (Solid State Music SB-1)

On 2022/09/19 9:51 p.m., ben via cctalk wrote: On 2022-09-19 10:18 p.m., Tom Hunter via cctalk wrote: There are a few US based Ebay sellers of the 74L85. Tom But most ebay sellers, from the USA seem to sell a item for $6.00 and $75 shipping to Canada. China $2 and $3 shipping. With Covid all

[cctalk] Re: 7485 chip history??? (Solid State Music SB-1)

Ben, I buy lots of stuff from eBay US sellers and most are willing to check/fix shipping costs. If not then I use a drop-box service where the item is shipped to Oregon, and then reshipped to me for a not too horrible cost. Lastly, I’ll be back at my shop in Burnaby in a couple of days and

Re: Retire cctech

On 2022/07/13 3:00 p.m., Dennis Boone via cctalk wrote: Folks, I've belatedly realized that it's going to be a bit of a headache to implement the old cctalk/cctech crossposting duality under the new version of mailman. I seem to recall a discussion about retiring the cctech list and just

Re: OT: mail provider recommendation

There ain’t no such thing as a free lunch! What did you think would happen with large free email hosts? They round up all the clients and then do what they like with them. Google mines emails for data. I use a private (paid) service via my web site host. I’ve been using it since around 1996.

Re: Replacement for a DEC 7474 Chip

On 2022/05/14 10:11 a.m., Rob Jarratt via cctalk wrote: Hello, I have found a bad DEC 7474 chip on my M7133 board. Clearly it is a 7474 D flip flop. The problem is I don't know which modern series would be the best one to replace it with. I am sure I have seen a list somewhere of modern

Re: Different font for second 1 on commodore 1571 drives (and others)

On 2022/05/05 10:26 a.m., Toby Thain via cctalk wrote: On 2022-05-05 1:03 p.m., John Herron via cctalk wrote: Someone at work pointed this out and I've never really thought about it. Is anyone here aware of the decision or reason to use a different 1 character for the last 1 vs the first 1?

Re: cleaning up edge connectors

On 2022/04/30 4:28 p.m., dwight via cctalk wrote: Yep. I didn't know it was now made by someone else. Also look at McMaster-Carr. You might get a better price. Dwight I've used Dow Corning #4 electrical grease for a couple of decades. It really helps preventing corrosion and reduces heating

Re: Looking for old OAK keyboard/control switch...

Link to image of switch: https://www.flippers.com/images/Misc/OAK_Pushbutton_Switch-1973.jpg Thanks, John :-#)# On 2022/04/29 2:14 p.m., John Robertson via cctalk wrote: I've been hunting for a few years for these switches and was thinking that perhaps folks here may have seen them or even

Looking for old OAK keyboard/control switch...

I've been hunting for a few years for these switches and was thinking that perhaps folks here may have seen them or even have some they wish to part with...I've hit all the surplus sites, and poured over old copies of old Radio Master Parts Catalogue/Encyclopedias - have 7 of those, from 1971

Re: Power Supply capacitor physical size

On 09/03/2016 10:07 AM, Adrian Graham wrote: On 03/09/2016 17:39, "Jon Elson" wrote: On 09/03/2016 10:56 AM, Noel Chiappa wrote: From: Jon Elson needs new caps since one of the 1000uF 16V ones has bulged badly. ... If I go up to 25V I can get 16mm diameter which is

Re: UNIBUS M9312 ROMS

On 06/08/2016 3:46 PM, Jay West wrote: I wrote... On Thu, Jun 9, 2016 at 6:34 AM, Jay West wrote: 23-E39A9 is still lost to time, afaik. TMSCP - TU81 To which mike replied... Could that not be reverse-engineered from the boot code in e.g. Emulex UC17 ROMs? They

Re: HP Draftmaster II 7596A: EPROM dumps needed, urgent :-(

On 05/21/2016 10:53 PM, David Collins wrote: Martin, I might be able to help you as I think we have a 7596A. Are these EPROMs from the processor PCA? Are you able to tell me which 'U' numbers they are in the PC board? I haven't looked at the plotter itself, but the service manual we have

Re: center tapped power transformer help needed

On 05/03/2016 8:51 PM, Jim Brain wrote: On 5/3/2016 10:48 PM, Chuck Guzis wrote: On 05/03/2016 08:08 PM, Jim Brain wrote: 60 Hz? Maybe you could give the guys at Prem Magnetics a call. They're always sending emails offering to do custom work. http://www.premmagnetics.com/ Yep, 50/60Hz. I

Re: Z80 /WAIT signal question

I do know that the Wait signal was used by the Fluke 90 tester so it could be clamped on top of an in circuit Z80 and run memory and I/O tests while the CPU was doing its regular operations. On vacation so haven't easy access to the operators manual for the Fluke 90 though... John :-#)# > On

Re: Fan bearing lubricant was Re: WD-40 (again)

On 04/17/2016 8:11 PM, Brent Hilpert wrote: On 2016-Apr-17, at 7:28 PM, Noel Chiappa wrote: Nope, the cylindrical (outer part of the) bearing is a plain cylinder. But looking at it closely, it's probably not copper, so it might be that Oilite stuff. Online images do give a fair idea of the

Re: Servicing DEC-T11 based products with a Fluke pod?

On 04/15/2016 12:22 PM, John Wallace wrote: Hi John, In the apparent absence of other T11-related suggestions, are you aware that there are a couple of T11-related manuals on Bitsavers, at least one of which has schematics? There's the T11 Users Manual, and the T11 Evaluation Module Users

Re: A tale of a chip and a socket

On 04/09/2016 5:29 AM, Noel Chiappa wrote: > From: Torfinn Ingolfsen > Most likely a bad solder joint. That was my first thought, and so I carefully inspected all the pins, but they all looked good to me. But I suppose it might have been something that wasn't visually obvious.

Re: Voltage regulator with alternate voltage source...

On 04/08/2016 8:54 AM, wulfman wrote: https://www.fairchildsemi.com/datasheets/LM/LM7805.pdf http://www.ti.com/lit/ds/symlink/lm78l05.pdf ( page 8 gives you the internals for a low power version ) Nothing in the data sheet saying you cant apply voltage to the output. As per the low power

Re: Voltage regulator with alternate voltage source...

you provide enough current it will probably self destruct. To me it is simple, the manufacturer says don't do it as you will damage the device. That is enough for me. If you want to check the internal die design you can see why this is so. John :-#(# On Thu, Apr 7, 2016 at 7:23 PM, John Robert

Re: Voltage regulator with alternate voltage source...

On 04/07/2016 2:18 PM, Bill Sudbrink wrote: drlegendre wrote: Not saying it's going to smoke-out, but it does seem like a wonky thing to do. I disagree about "wonky" let me try with more diagram and less English: (+8) | VIN|ceramic cap |-][- ___| | |

Re: Voltage regulator with alternate voltage source...

On 04/07/2016 2:25 PM, geneb wrote: On Thu, 7 Apr 2016, Bill Sudbrink wrote: Maybe I'm overthinking this. If I just put regulated +5 on the 7805 VIN will it work? Isn't the minimum input voltage for a 7805, 6vdc? g. More like 7VDC input minimum (dropout voltage) for 7805 - there are data

Re: Voltage regulator with alternate voltage source...

On 04/07/2016 2:03 PM, William Donzelli wrote: Per his description, the 7805's input will be open. It will not try to source any current, as it will have none to give. I suppose there might be a little leakage. -- Will If his intention is to bypass the 7805 then it should have both input

Re: Usenet News Servers

On 03/06/2016 6:49 AM, Dave G4UGM wrote: I think Thunderbird will allow import from the old Netscape mail client. Dave I access Giganews via Thunderbird (OSX) - works very well... The downside is it costs about $8/month, but that is a very small business expense. Upside is Giganews goes

Re: Old MOS Mask-Programmed ROM forgetfulness?

On 02/16/2016 12:43 PM, dwight wrote: It is interesting, I have 1702As that were programmed in 1973 sometime and they still have their data ( used on my SIM4-01 ). And yes, I have them backed up. It is interesting that Data I/O has added supply current checks. I've used many home made pin

Re: Old MOS Mask-Programmed ROM forgetfulness?

On 02/15/2016 11:25 PM, Eric Smith wrote: On Mon, Feb 15, 2016 at 11:31 PM, John Robertson <j...@flippers.com> wrote: Rick, if you want to archive these PROMs (highly recommended) you should be able to find a Data I/O 29B and get one of the programming packs that supports NS chips. I ma

Re: Old MOS Mask-Programmed ROM forgetfulness?

On 02/15/2016 10:25 AM, Rick Bensene wrote: Hi, all, I have a question about old Mask-Programmed ROMs The part in question is the National Semiconductor MM5231. This part is a 2K-bit PMOS Mask-Programmed ROM, generally organized as 256x8, but also can be organized (via a MODE pin)as 512x4

Re: Stuck bits on 11/73 Clearpoint 4MB memory - how to repair?

On 02/12/2016 6:55 PM, Jay Jaeger wrote: On 2/12/2016 5:32 PM, Jacob Ritorto wrote: Hi, Seems I have bits 4 and 3 sticking on my Clearpoint QRAM-2-SAB-1 88b 4MB memory in my pdp11/73. Can anyone offer hints as to how to identify which component is broken and how to go about repairing

Re: NiCd battery replacement in vintage computers

On 02/06/2016 1:29 PM, Paul Koning wrote: On Feb 6, 2016, at 4:21 PM, Mark J. Blair wrote: Today I discovered that I hadn't replaced the NiCd battery in time in my Amiga 3000. Pictures: ... While I begin to figure out how I'd like to perform this repair, I'm curious about what

Re: NiCd battery replacement in vintage computers

On 02/06/2016 1:29 PM, Paul Koning wrote: On Feb 6, 2016, at 4:21 PM, Mark J. Blair wrote: Today I discovered that I hadn't replaced the NiCd battery in time in my Amiga 3000. Pictures: ... While I begin to figure out how I'd like to perform this repair, I'm curious about what

Re: Restoring Old Paper Tape

On 01/21/2016 6:46 PM, Charles Anthony wrote: On Thu, Jan 21, 2016 at 6:21 PM, Jason T wrote: On Thu, Jan 21, 2016 at 8:04 PM, Charles Anthony wrote: For part 2, personally, I would take movies of the paper tape moving and doing image

Re: Data Recovery Services

On 01/20/2016 11:22 AM, JC White wrote: I need to recover some files from a SCSI drive that failed over a decade ago. Are there data recovery services that can determine if the files on the drive can be recovered or can actually do such a recovery? Now that I think about it, I recently also

Re: Data Recovery Services

On 01/20/2016 2:00 PM, Mark Linimon wrote: On Wed, Jan 20, 2016 at 12:35:22PM -0800, John Robertson wrote: If the drive's PCB turned out to be the problem, could an identical drive model act as a donor for a known-to-be-good PCB? I've done this on modern drives. It is not particularly tricky

Re: Building a PC - then & now

On 01/13/2016 4:54 PM, Chuck Guzis wrote: On 01/13/2016 03:27 PM, William Donzelli wrote: In the old days, the shitty kit TVs would have continuous tuners. In prewar days, it seems that there more than a couple of offerings. Didn't Meissner(they of the "Signal Shifter" VFO) offer a kit TV

Free (pay shipping) Hp DDS-4 40gb tapes (only have two)

I have two sealed C5718A tapes that are free to the first person to ask for them and pay shipping. I hate to throw out something that may still be useful. Can mail them for $5 (I think) to the USA, or local pickup. John :-#)# -- John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9

Re: Floppy recovery

On 01/05/2016 1:15 PM, Ali wrote: Anyone know anything about the custom computer and the custom OS? Nor implying anything but Chuck do u have any insights? ;) Didn't Scotty leave his laptop behind when they were saving the whales? John ;-#)#

Re: "Bounce buffer" copyright [was Re: flash (or ide) storage for unibus 11?]

On 11/28/2015 3:41 PM, Mouse wrote: Love that term, "bounce buffer" (I wrote a whole package to support them in a packet switch I did) - I'm officially adopting it, right now! :-) Hey - anything that anyone writes is automatically copyrighted. I realize you...may have been less than entirely

Re: PROMs and EPROMs, specifically 2332/2532/2732

On 10/25/2015 4:37 PM, Adrian Graham wrote: On 25/10/2015 17:19, "John Robertson" <j...@flippers.com> wrote: Hi John and others, Thanks for that. I removed the diodes and wired 2332 (21) to 2372 (24) leaving the A11 swap in place, the programmer complained about pin 18 miss

Re: PROMs and EPROMs, specifically 2332/2532/2732

On 10/24/2015 5:56 PM, Adrian Graham wrote: On 24/10/2015 19:18, "John Robertson" <j...@flippers.com> wrote: On 10/24/2015 5:43 AM, Adrian Graham wrote: Hi folks, PET4032 repair continues with all ROMs, video RAM and dodgy sockets removed thanks to a hot air gun. Holes cl

Re: PROMs and EPROMs, specifically 2332/2532/2732

On 10/24/2015 5:56 PM, Adrian Graham wrote: On 24/10/2015 19:18, "John Robertson" <j...@flippers.com> wrote: On 10/24/2015 5:43 AM, Adrian Graham wrote: Hi folks, PET4032 repair continues with all ROMs, video RAM and dodgy sockets removed thanks to a hot air gun. Holes cl

Re: PROMs and EPROMs, specifically 2332/2532/2732

On 10/24/2015 5:43 AM, Adrian Graham wrote: Hi folks, PET4032 repair continues with all ROMs, video RAM and dodgy sockets removed thanks to a hot air gun. Holes cleaned and I have new turned pin sockets for everything I've removed which I'll be fitting this afternoon. Since the ROMs came out

Re: Computers in Election Vigils - take two

On 10/09/2015 4:50 AM, Alexandre Souza wrote: lucky you. In Brazil we use vote machines made by diebold, which are as weak in security as a carton box. And no independent entity can ressearch its failures. After the fiasco about the Deibold machines changing votes during the Bush election of

Re: ESR Meter Recommendations

On 09/30/2015 7:14 AM, Jay West wrote: John wrote That is an authorized Bob Parker variation of his original Dick Smith ESR meter kit. On this side of the pond they were made by Anatek until the owner was killed in an accident, then the series (now called the Blue ESR) is made by

Re: ESR Meter Recommendations

On 09/30/2015 7:14 AM, Jay West wrote: John wrote That is an authorized Bob Parker variation of his original Dick Smith ESR meter kit. On this side of the pond they were made by Anatek until the owner was killed in an accident, then the series (now called the Blue ESR) is made by

Re: ESR Meter Recommendations

On 09/29/2015 2:59 PM, Jay West wrote: This is the one I have used for years. http://clientes.netvisao.pt/greenpal/evb1.htm About $88 USD J That is an authorized Bob Parker variation of his original Dick Smith ESR meter kit. On this side of the pond they were made by Anatek until

Re: 21MX proms (per request)

On 09/06/2015 2:00 PM, Alexandre Souza wrote: Jay, no one is pin compatible, I always make adapters. But at least I make it work :D 2015-09-06 16:00 GMT-03:00 Jay West : Alexander wrote... - Intersting to note: many times i have used eproms in place of these proms.

Re: Reading ROMs

On 09/03/2015 4:56 AM, Vlad Stamate wrote: While I was trying to read the ROM in my 9121 for Eric Smith I found out that my Wellon VP-280 could not do it (it could not recognize it and only read FF FF FF FF). I could use it however to dump the ROM of an IBM PS2 that I cannot boot anymore (so it

Re: Data I/O 29B

On 08/21/2015 5:33 PM, Billy Pettit wrote: I have a small batch of Data I/O EPROM burners. Trying to test them out and ran into a nightmare. They require a pin family and size parameter. But in none of the documentation is there any mention of what these values are. There are some generic

Re: Unidentified chip

On 08/04/2015 1:48 PM, dwight wrote: This all assumes it is a TTL and not an ECL or even and analog chip, such as an opamp. Dwight It might be possible to identify it a bit. Using the Diode Test of your basic multi-meter you can probably figure out if

Re: Huge news! MARCH's 501c3

On 07/27/2015 7:40 PM, Evan Koblentz wrote: He did say that they got permission from Sellam (and Erik K.) Correct. We briefed them both on our plans several months ago and they're both on board. Also, a technicality that I neglected to say earlier: MARCH didn't become the Federation;

Re: Chromatics on ebay

On 07/23/2015 2:15 PM, William Donzelli wrote: That's just seller's remorse. It's obviously up to you, but I'd have strongly considered disputing it with eBay as a seller refusing to honor the auction results is every bit as bad (or even worse) than a buyer refusing to honor the auction result.

Re: PDP 11 gear finally moved

failure was caused by static electric shock to the machine would blow the supply. NO carpets allowed!! John :-#)# On 07/17/2015 2:19 PM, Jay Jaeger wrote: U - his PDP-11/34 most certainly does use switching power regulators. ;) On 7/17/2015 4:06 PM, John Robertson wrote: On 07/17/2015 11

Re: PDP 11 gear finally moved

On 07/17/2015 11:53 AM, Mouse wrote: I do find this witch-hunt against capacitors to be curious, given how few I've found to have failed. I suspect a lot of it comes from audiophools who think this is the way to fix anything... Perhaps. But not all of it, certainly. I'm currently four for

Re: email gripe

On 07/07/2015 4:44 PM, Chris Osborn wrote: On Jul 7, 2015, at 4:18 PM, Chuck Guzis ccl...@sydex.com wrote: using Thunderbird Which I’ve noticed has problems parsing the General Discussion: On-Topic and Off-Topic Posts cctalk@classiccmp.org No matter which platform anyone is using,

Re: Reading/Verifying the Intel 8041A

On 05/20/2015 7:15 PM, Richard B. Main, Esq. wrote: The Intel AFN-00188B Datasheets for 8041A/8741A specify that EA max is 24.5V. The verify mode for PROM/ROM holds EA high at 23V. The 8048/8748 Datasheets say EA is 32V for 8748 Verify but need only be +12V for 8048. Richard Speaking of old