Re: VAXmate PSU

On 2020-Apr-05, at 2:53 PM, Rob Jarratt wrote: > I have obtained a scope trace as you suggest. R32 is still lifted so the > UC3842 is powered by the bench PSU, but I am using the full 240VAC (no > variac). The channels are: > 1.Ch1. 555 timer. > 2.Ch2. D19 Anode > 3.Ch3. D19 Gate. > 4.

Re: State of New Jersey needs COBOL programmers

Here in Canada, ongoing for several years now, we've had the major fiasco of the Phoenix payroll system. I've never heard an accounting of where the fault lies, or why IBM isn't being held more accountable. A brief summary from Wikipedia: The Phoenix pay system is a payroll processing system for

Re: VAXmate PSU

On 2020-Apr-05, at 11:12 PM, Rob Jarratt wrote: >> >>> I have obtained a scope trace as you suggest. R32 is still lifted so >>> the >>> UC3842 is powered by the bench PSU, but I am using the full 240VAC (no >>> variac). The channels are: >>> 1. Ch1. 555 timer. >>> 2. Ch2. D19 Anode >>> 3. Ch3.

Re: Great, my VT52 is shot.

On 2020-Apr-15, at 5:23 PM, Chris Zach via cctalk wrote: > Wonderful: A few weeks ago I forgot to turn off my VT52 and left it running > for a day or two. Now the screen is filled with snow and it looks like the > text is all over the place horozontally. > > Any tips or thoughts on where to s

Re: Another Unrelated PSU Question

On 2020-Apr-18, at 10:03 AM, Rob Jarratt via cctalk wrote: > I have another PSU I have been meaning to look at for a long time. This one > has fairly high output ripple and some of the voltages do not appear to be > where they should be. I have checked all the capacitors for ESR and they > appear t

Re: Great, my VT52 is shot.

On 2020-Apr-19, at 3:09 PM, Chris Zach via cctalk wrote: >> As I wrote earlier in the thread I think it is a good idea to check the V >> sync and H sync signals to check that they are right in pulse length and >> shape. > > Good starting point. From the schematics would that be scope probe to J

Re: Great, my VT52 is shot.

On 2020-Apr-21, at 7:57 AM, Chris Zach via cctalk wrote: > Well I'm starting to walk through this. First I took an IR picture of the > boards in operation, then started troubleshooting. > > First I started checking voltages. J2 is easily accessible so I put a ground > probe on pin 10, and checke

Re: Great, my VT52 is shot.

On 2020-Apr-21, at 5:27 PM, Chris Zach via cctalk wrote: > Meantime reading the manual I found an interesting test: If you short emitter > to base on Q4 (easiest way is to jumper diode D10) the voltage on the -12v > supply goes to .4 volts. They're saying it's E2, R15,R17,R14. > > Is there a way

Re: Great, my VT52 is shot.

On 2020-Apr-21, at 8:35 PM, Chris Zach wrote: >> The D8 5V ref and the targetted output V are divided via R15 and R17,R18 to >> provide the sense input at E2.2. >> If one does the R ratio of the three resistors, it comes out, as would be >> expected, to ~ 0V. > > Ah hah, that is clever. I wonder

Re: Ok, got the Perq tapes

On 2020-Apr-26, at 4:33 PM, Chris Zach via cctalk wrote: > Latest pictures are at https://www.crystel.com/bob . https://www.crystel.com/bob/DSC_0255.JPG HP 9825 (the ochre keyboard) underneath the PCB.

Re: Hopefully on topic

On 2020-May-04, at 8:10 PM, Martin Crockett via cctalk wrote: > .. > I noticed there is a capacitor that has vaporized, but I cant determine > what value it is. > > I have the DEC VT-100 maintenance guide but it is very blurry in the > relevant area. > > I cant even read the board designation. >

Re: MicroVAX 3100 Model 95 Ripple

On 2020-May-09, at 9:32 AM, Rob Jarratt via cctalk wrote: > I have recently been trying to improve the ripple on the output of my > MicroVAX 3100 Model 95 PSU because occasionally it would fry a memory > module. I replaced a bunch of capacitors, some of which had started to leak. > However, the rip

Re: Someone's confused

On 2020-Jun-07, at 8:30 AM, Noel Chiappa via cctalk wrote: > Love the title on this: > > https://www.ebay.com/itm/184317705963 > > eBait auction: "16K Sense Inhibit Board .. VAX 6000, VAX-11/730". > Yeah, core on a VAX! And such a deal, a mere US$400! To add to the weirdness, here are some actu

Re: Ever seen a Cromemco Cyclops in the wild?

On 2020-Jun-09, at 6:21 AM, Shoppa, Tim via cctalk wrote: > I think a Stanford AI lab has one in a display case. Any others out there? > > It was supposedly "commercial" but I don't even remember ever seeing an ad > for the Cyclops from Cromemco and I had a really good stash of Cromemco > litera

Re: In search of 4B3A Microswitch Keyswitches (for a system restoration, not keyboarding)

On 2020-Jul-09, at 9:39 PM, Ian Finder via cctalk wrote: > I know what you guys are thinking- no, this isn't for a keyboard collection > or some modern build or some other nonsense like that. > > I have a friend who is restoring a fairly interesting and historically > significant vintage computer

Re: In search of 4B3A Microswitch Keyswitches (for a system restoration, not keyboarding)

On 2020-Jul-09, at 10:12 PM, Ian Finder wrote: >> On Jul 9, 2020, at 21:58, Brent Hilpert wrote: >> On 2020-Jul-09, at 9:39 PM, Ian Finder via cctalk wrote: >> >>> I know what you guys are thinking- no, this isn't for a keyboard collection >>> or some modern build or some other nonsense like tha

Re: In search of 4B3A Microswitch Keyswitches (for a restoration, not a keyboard collector!)

On 2020-Jul-10, at 11:27 AM, Ian Finder via cctalk wrote: > On Fri, Jul 10, 2020 at 11:06 AM Al Kossow via cctalk > wrote: >> >> Since it isn't very fancy, I wonder if you could make a new board with a >> modern Hall >> effect sensor? You just need a contact closure. > Yeah Al, that's a great su

Re: Any interest in "newer" hardware, software?

Fairchild part numbers trivia following. On 2020-Jul-28, at 7:35 AM, Jay Jaeger via cctalk wrote: > My DTL chips have markings like: > > DT uL93659 (Chip type 936) > F 7016 > > DT uL909759 (Chip type 9097) > F 7013 > > (I expect 7016 and 7013 are date codes. Not sure what the "59" is abou

Re: Any interest in "newer" hardware, software?

On 2020-Jul-28, at 4:48 PM, Carlos E Murillo-Sanchez via cctalk wrote: > > So, what would two chips marked > > F U6A7709393 > 7043 F : Fairchild U : monolithic device (as opposed to e.g. hybrid) 6A : package, DIP (6), 14-pin (A) 7709: circuit/function code. As Jay suggests, a 709 op

Re: Any interest in "newer" hardware, software?

On 2020-Jul-28, at 6:40 PM, Jay Jaeger via cctech wrote: > On 7/28/2020 1:43 PM, Brent Hilpert via cctech wrote: >> >> Per the OP's machine, the early HP21xx machines were based on CTµL, for >> which the main supply is +4.5V. >> DTL and TTL chips in these machines ran off that 4.5 supply. >>

Re: [GreenKeys] Omaha craigslist - Teletype RO printer - what model?

On 2020-Aug-03, at 12:34 PM, John Foust via cctalk wrote: > At 12:56 PM 8/3/2020, Nick England wrote: >> Looks interesting - I know nothing more >> https://omaha.craigslist.org/sys/d/omaha-heathkit-h19-term

Re: Help Identifying Components

On 2017-Dec-24, at 10:27 AM, Rob Jarratt via cctalk wrote: > I am continuing work to reverse engineer the schematic for my H7826 PSU. I > have removed one of the daughter cards in order to draw its schematic, but I > can't identify some of the surface mount components on it. I have posted a > pictu

Re: Help Identifying Components

On 2017-Dec-24, at 12:01 PM, Chuck Guzis via cctalk wrote: > On 12/24/2017 11:15 AM, Rob Jarratt wrote: > >> I think the orange components are capacitors (they are taller than the >> browner ones), but their markings don't seem to hint at the values, some are >> marked "AA4", which does not seem

Re: Non-Yahoo MTS Mailing Lists

On 2017-Dec-30, at 6:26 PM, Adrian Stoness via cctalk wrote: > mts??? > > as in manitoba telcome services now known as bellmts?? No, Michigan Terminal System. A timesharing system for IBM 360/370 series mainframes, used and maintained at a number of universities from the late 60s through ear

Re: Computing from 1976

On 2018-Jan-01, at 5:06 PM, Paul Koning via cctalk wrote: >> On Jan 1, 2018, at 3:57 PM, David Bridgham via cctalk >> wrote: >> On 01/01/2018 03:33 PM, Noel Chiappa via cctalk wrote: From: Paul Koning >>> The only asynchronous computer I can think of is the Dutch ARRA 1 >>> >>> Isn't

Re: Help identifying IC

The mid-70s saw a plethora of dedicated-logic LSI TOD clock chips in 24-28 and sometimes 40 pin packages. Most prevalent IME were those made by National, Mostek and Fairchild. Going by the labelling for the other two chips, fair chance the ID of the big chip is staring right at us: MPS 7123. Mic

Re: Sun3 valuations?

On 2018-Jan-22, at 1:24 AM, Pete Lancashire via cctalk wrote: > My interest would be from having the first Sun systems in the Portland > Oregon area. It consisted of a 3/260 w a Fujitsu Eagle, and a 90 ips 9 > track that I cant remember the make. > Tied to it where 3 3/50s. Initially diskless then

Re: Sun3 valuations?

On 2018-Jan-22, at 1:24 AM, Pete Lancashire via cctalk wrote: > My interest would be from having the first Sun systems in the Portland > Oregon area. It consisted of a 3/260 w a Fujitsu Eagle, and a 90 ips 9 > track that I cant remember the make. > Tied to it where 3 3/50s. Initially diskless then

Re: Ethernet cable (Was: Sun3 valuations?)

On 2018-Jan-23, at 12:27 PM, Paul Koning via cctalk wrote: > The Ethernet spec says that the cable OD is in the range .365 to .415 inch, > which is 9.27 to 10.54 mm. The nominal OD of RG-8/U is .405 inches, or 10.28 > mm, which is within spec for Ethernet cable. > > One place where the two cabl

Re: Bendix G-15 [was: Re: VCF PNW 2018: Pictures!]

On 2018-Feb-18, at 11:30 AM, Mark Linimon via cctalk wrote: > On Sun, Feb 18, 2018 at 01:04:38PM -0600, Jon Elson via cctalk wrote: >> Wow, even a Bendix G-15 in there (although with Control Data logo). > > Nope, look again, there are two :-) > >> Talk about a restoration project!!! > > AFAIK th

Re: Bendix G-15 [was: Re: VCF PNW 2018: Pictures!]

On 2018-Feb-18, at 11:57 AM, Al Kossow via cctalk wrote: > On 2/18/18 11:53 AM, Brent Hilpert via cctalk wrote: > >> Paul Pierce has a G-15: >> http://www.piercefuller.com/collect/bendix/index.html >> >> Or he did, ca 2001. > &

Re: Looking for opinions...

On 2018-Mar-28, at 6:52 PM, Fred Cisin via cctalk wrote: [...] > If only that were 16mm or 35mm continuous rolls, instead of microfiche! > > In 1931, Emanuel Goldberg, then a chief engineer at Zeiss built the > "Statistical Machine". By recording bits optically in the margins of > microfilm, a

Re: Old core memory system.

On 2018-May-05, at 2:57 AM, Mattis Lind via cctalk wrote: > Can anyone tell what kind of computer this might have been connected to? > > https://i.imgur.com/IC3AVCf.jpg > > I googled MS8192X26-1.9-RT and found one hit: > > http://www.nsn-now.com/Indexing/ViewDetail.aspx?QString=7025013480747 >

Re: Looking for info on Motorola 4015 chip

On 2018-May-12, at 11:03 AM, Noel Chiappa via cctalk wrote: > Hey, all, the RK11-D contoller for the PDP-11 uses Motorola 4015 MSI chips on > one of the boards (M7254), but I can't find out anything about them. Google > didn't turn anything up, and the appendix in the RK11-D Maintenance Manual > th

Re: Thicknet/10base5 Test Segment: The Cable is In!

On 2018-Jun-29, at 1:27 AM, Peter Coghlan via cctalk wrote: > > A telephony connection is the most plausable theory I have come across yet. > I can remember devices that looked like large junction boxes with a ground > connection that were installed where an overhead telephone line entered a > bui

Re: Looking for Tektronix 4051 or 4052 Display Board

On 2018-Jul-03, at 1:21 PM, Monty McGraw via cctalk wrote: > I've been repairing my Tektronix 4052. > > I've got the digital logic working - but the text and graphics are messed > up. > > I posted photos of the screens in my Tektronix 4052 troubleshooting thread > on vcfed. > > With a scope on t

Re: Looking for Tektronix 4051 or 4052 Display Board

On 2018-Jul-03, at 5:06 PM, Brent Hilpert via cctalk wrote: > However, compare to: > https://drive.google.com/file/d/1TJjeZqszca1C7XILsnDyO9D_r64ZMwoo/view > the 2 & 3 pin labels on U184A should be swapped. Whoops, correction to my correction, they got the pins right, but

Re: Looking for Tektronix 4051 or 4052 Display Board

On 2018-Jul-03, at 5:59 PM, Jon Elson via cctalk wrote: > On 07/03/2018 03:35 PM, Ian Finder via cctalk wrote: >> On Tue, Jul 3, 2018 at 1:21 PM, Monty McGraw via cctalk < >> cctalk@classiccmp.org> wrote: >> >>> I've been repairing my Tektronix 4052. >>> >>> I've got the digital logic working - b

Re: BASIC (Was: Reading HP2000 tapes

The HP9830 (1972) with it's ROM'ed BASIC works this way. LIST produces a 'cleaned up' version of the source code. On 2018-Jul-17, at 1:21 PM, Guy Sotomayor Jr via cctalk wrote: > I should also mention that for the IBM S/23, once the BASIC program is > entered, the original > source is discarde

Re: MOS MCS2529 math chip

On 2018-Jul-20, at 10:18 AM, Jules Richardson via cctalk wrote: > Anyone got pinout/spec information for a MOS MCS2529? In particular, I'm > curious about operating voltage. I acquired a Melcor SC-635 calculator > yesterday and there seems to be some uncertainty about the output voltage of > its

Re: HP-2116 front panel lamps

On 2018-Jul-25, at 6:47 AM, Christian Corti via cctalk wrote: > On Wed, 25 Jul 2018, it was written >> Christian, when I was restoring the HP Computer Museum's 2116A I ordered a >> bunch of these 345 bulbs from 1000bulbs.com - but it seems they no longer >> stock them. >> >> I did find this listin

Re: Some late fifties HP measurement equipment available. ( Switzerland )

On 2018-Sep-03, at 8:39 AM, jos via cctalk wrote: > the following late fifties HP equipment is available in Switzerland. > Stored in less than ideal conditions, but seem otherwise quite OK. > > Feel free to forward to more fitting mailing list / fora. > > Not my equipment, my only interest in thi

Re: DEC H744 +5 supply

On 2018-Sep-21, at 12:38 PM, Noel Chiappa via cctalk wrote: > So there's something about the H744 I'm not sure I understand; hopefully those > with more analog-fu will set me straight if I'm confused. > > This supply runs off 20-30V AC. It takes the input AC, rectifies it, and runs > it through

Re: DEC H744 +5 supply

On 2018-Sep-21, at 1:03 PM, Noel Chiappa via cctalk wrote: > Oh, one thing I forgot to include: > >> a lot of the incoming power in that 30V AC has to be thrown away, in >> producing +5V. > > So, if my understanding is correct, the 'switching' H744 really isn't much > better than a classic linear

Re: DEC H744 +5 supply

On 2018-Sep-21, at 3:20 PM, Noel Chiappa via cctalk wrote: >> From: Mattis Lind > >> The H744 is a buck converter. You can read about buck converters here: >> https://en.wikipedia.org/wiki/Buck_converter > > Wow, that was incredibly hard to read; no clear and simple explanation of the > basic

Re: DEC H744 +5 supply

On 2018-Sep-21, at 4:03 PM, Noel Chiappa via cctalk wrote: >> From: Brent Hilpert > >> If the heatsinks seem huge compared to modern day supplies, that's more >> likely the result of technology improvements - faster devices, and >> moving from bipolar switching transistors to mosfets. Bipolar >> t

Re: DEC H744 +5 supply

On 2018-Sep-21, at 4:03 PM, Noel Chiappa via cctalk wrote: >> From: Brent Hilpert > >> In typical "down-converters" there are additional current paths in the >> supply, paralleling the input path, that can provide the 'additional' >> electron flow rate. ... the whole rationale of a switching su

Re: DEC H744 +5 supply

On 2018-Sep-22, at 11:54 AM, Noel Chiappa via cctalk wrote: >> From: Brent Hilpert > >> A glance at the schematic ... you might think it's just a linear >> regulator > > And the writeup in the maint manual gives that impression too, which didn't > help! (Hence my assumtion that it was acting in t

Re: SPACEWAR! Switch Boxes for a PDP-12

On 2018-Sep-23, at 7:46 AM, Michael Thompson via cctech wrote: > Visitors to the RICM like to play SPACEWAR! in the PDP-12. Unfortunately > using the console switches is uncomfortable, not intuitive, and is tough on > the switches. We would like to recreate the switch boxes used on the PDP-1 > to m

Re: SPACEWAR! Switch Boxes for a PDP-12

On 2018-Sep-23, at 7:46 AM, Michael Thompson via cctech wrote: > Visitors to the RICM like to play SPACEWAR! in the PDP-12. Unfortunately > using the console switches is uncomfortable, not intuitive, and is tough on > the switches. We would like to recreate the switch boxes used on the PDP-1 > to

Re: Does anyone recognise these boards please

On 2018-Oct-05, at 5:38 PM, Kevin Parker via cctalk wrote: > Be most grateful if anyone can advise here please. Rescued a TRS-80 MC10 from > deceased estate recently - it was headed for the bin > but got saved. > > The original owner was a bit of an electronics hobbyist and his > brother-in-law

Re: behaviour of classic PDP-8 frontpanel

On 2018-Oct-30, at 8:07 AM, Klemens Krause via cctalk wrote: > Is there anybody out with a working classic PDP-8? > > For a long time we had the problem, that starting a program on our 8 by > pressing keys, this program crashed. Examining the memory > contents showed, that typically one or two

Re: A very sad PDP-8/S

On 2018-Nov-03, at 9:27 PM, Guy Dunphy via cctalk wrote: . . . > The front panel is in pieces atm. And clean now. > Incidentally, several people called the material used for the lamps shroud > plate 'MDF.' > It's not, it's that high density cloth+bakelite (or something) material used > for electr

Re: Zuse Z4 - Oldest Surviving Computer in the World - Lost in the archives

On 2020-Oct-01, at 2:03 PM, Paul Koning via cctalk wrote: >> On Oct 1, 2020, at 1:20 PM, dwight via cctech wrote: >> >> It is going to need a lot of contact cleaning. >> The one thing I like is the carry design the Zuse used. Really fast for >> relays but not of much use for solid state. >> Dwig

Re: Identifying mystery TI ICs (Motorola MDP-1000 investigation continues...)

On 2020-Oct-04, at 1:22 AM, Josh Dersch via cctalk wrote: > More mysteries while poking at the MDP-1000. Spent some time this evening > working out the rest of the signals on the power harness (I suspect inputs > for an LTC circuit and a "power good" signal, as well as something > connected to a

Re: Anyone want to part with a DEC MXV11-B (M7195) and/or M8012 (BDV11)?

On 2020-Oct-04, at 1:14 PM, Chris Hanson via cctalk wrote: > Thanks to everyone who replied, on- and off-list! There’s an MXV11-B (M7195) > on its way to me. :) > > Since people were asking about my setup, here’s what I have: > > - MDB BA11-clone enclosure, PSU, and 8-slot 22-bit backplane >

Re: Anyone want to part with a DEC MXV11-B (M7195) and/or M8012 (BDV11)?

On 2020-Oct-04, at 1:55 PM, Chris Hanson wrote: > On Oct 4, 2020, at 1:53 PM, Brent Hilpert wrote: >> >>> For the latter two, I need to figure out whether my backplane supports ABCD >>> use in the first couple of slots, or if it’s purely an ABAB model. (The >>> KDF11-A, RLV12, and MLSI-SCM11 ca

Re: when was memory "above" the terminal screen invented?

On 2020-Dec-13, at 6:37 PM, Stan Sieler via cctalk wrote: > ... > When was the concept of memory "above" the screen invented for terminals? > > I.e., previously displayed data that had scrolled up and off the screen ... > but could be retrieved (usually by scrolling down). > > (Sometimes called

Re: tty and video displays

On 2020-Dec-14, at 1:26 AM, ben via cctalk wrote: > Often for data input one could use over strike characters for input. Not EQ > might be = BS | Did any video display terminals > repeat the same effect? Yes. Coincidentally I've just been refurbishing one - a Teleray 3931. It's an ASCII/APL termi

Re: tty and video displays

On 2020-Dec-14, at 6:28 AM, Paul Koning wrote: >> On Dec 14, 2020, at 9:26 AM, emanuel stiebler via cctalk >> wrote: >> On 2020-12-14 05:41, Brent Hilpert via cctalk wrote: >>> On 2020-Dec-14, at 1:26 AM, ben via cctalk wrote: >>>> Often for data input o

Re: tty and video displays

On 2020-Dec-14, at 7:57 AM, Jules Richardson wrote: > On 12/14/20 4:41 AM, Brent Hilpert via cctalk wrote: >> >> Yes. Coincidentally I've just been refurbishing one - a Teleray 3931. >> It's an ASCII/APL terminal, overstriking was included for the APL mode. >>

Re: tty and video displays

On 2020-Dec-15, at 11:15 AM, Jules Richardson via cctalk wrote: > On 12/14/20 10:06 PM, Brent Hilpert via cctalk wrote: >>> (It's definitely -12V, not -5V? I'm just thinking that the -12V noted >>> on your schematic is quite close the the 15V rating on the cap - >

Re: Mystery (unusual) 1973 terminal

On 2021-Feb-12, at 6:08 AM, Paul Koning via cctalk wrote: >> On Feb 12, 2021, at 7:50 AM, Jules Richardson via cctalk >> wrote: >> >> Hopefully the following link works, but someone over on one of the Facebook >> vintage groups has this oddball terminal from 1973 that they've been looking >> f

Re: : Re: MSI 6800 EPROM Software

On 2021-Feb-23, at 1:45 PM, Frank Tuccio via cctech wrote: > On 02/22/2021 01:31 PM, Brad H via cctalk wrote: >> >> A longshot I'm sure - but I am wondering if anyone familiar with MSI > (Midwest Scentific - SS50 bus system) would happen to have a copy of the > software for their 1702A EPROM burne

Re: Hard To Believe This Person Is Serious

On 2021-Mar-25, at 5:21 PM, Chris Zach via cctalk wrote: > Well, if there is no cost to asking that amount, why not? It's an > inefficiency of Ebay that things can stay up there for years, but that is as > it is. It's been enough years I don't remember when I first saw it, this has been listed

Re: Need a BASIC expert

On 2021-Apr-21, at 1:49 AM, Christian Corti via cctalk wrote: > I'm trying to find out if the BASIC dialect that was available for the MINCAL > computers (aboutn 1971) was something derived from another "system" or > whether it was an own dialect. > > Some characteristic instructions that I can'

Re: Exidy S-100 Expansion cards questions

On 2021-Apr-24, at 12:43 PM, David Williams via cctalk wrote: > Moving forward on setting up my collection and I was taking a look at an > Exidy Sorcerer S-100 Expansion box I had received long ago. I wondered if > anyone could help with info on the cards I found inside. The first is clearly >

Re: Motor generator

On 2021-May-04, at 4:06 PM, Donald via cctalk wrote: > In the deep recesses of my mind I seem to remember something about S/360 > machines using a motor generator. > > If I am right was this to create a stable power source at a certain > frequency or voltage? I dont know about the 360, but a moto

Re: Apple II+ Video questions

On 2021-May-09, at 2:16 PM, David Williams via cctalk wrote: > Working on restoring my very first computer, an Apple II+. Got it mostly > working with just a couple of issues identified at the moment. Some of the > keys on the keyboard don't register but I can work on that. The real question > I

Re: DEC Computer Lab for sale

On 2021-May-29, at 7:58 AM, William Donzelli via cctalk wrote: > Over on the Discord, I have posted a DEC Computer Lab H-500 for sale. > Needs cosmetic help, but will be priced accordingly. > > Offers? Off list... As I am aware of it Discord is a software package. What does "Over on the Discord

Re: Early Programming Books

On 2021-Jun-20, at 7:38 PM, ben via cctech wrote: > On 2021-06-20 8:13 p.m., Toby Thain via cctech wrote: > >> Tried the Shunting Yard algorithm? But watch out, it was invented by a >> quiche eater... > > The problem needs backtracking to generate correct code. Stack or > muilti-register machine

Re: Early Programming Books

On 2021-Jun-20, at 9:19 PM, ben via cctalk wrote: > On 2021-06-20 9:01 p.m., Brent Hilpert via cctalk wrote: >> On 2021-Jun-20, at 7:38 PM, ben via cctech wrote: >>> On 2021-06-20 8:13 p.m., Toby Thain via cctech wrote: >>> >>>> Tried the Shunting Yard algor

Re: Early Programming Books

On 2021-Jun-20, at 7:38 PM, ben via cctech wrote: > On 2021-06-20 8:13 p.m., Toby Thain via cctech wrote: > >> Tried the Shunting Yard algorithm? But watch out, it was invented by a >> quiche eater... > > The problem needs backtracking to generate correct code. Stack or > muilti-register machine

Re: VT100 colors

This is funny, as everyone (me too) weighs in with their description of the elephant. My recollection (also from recent observation of a VT278): - case main: very light cream, somehow with a touch of grey, but not pure white - case insets: very dark brown Remember, it was the 70

USB Serial conversion / was Re: VT340 Emulation

On 2021-Jun-26, at 10:15 AM, Paul Koning via cctalk wrote: >> On Jun 26, 2021, at 11:31 AM, Tapley, Mark B. via cctalk >> wrote: >> >> At one point FTDI had a reasonably good reputation, and I own one of those >> devices based on that reputation. I have used it with no obvious problems >> conn

Re: core matt repair

On 2021-Jul-20, at 4:04 PM, Jules Richardson via cctech wrote: > On 7/20/21 12:13 PM, pspan via cctech wrote: >> I worked at a company called DMA located in Amery Wisconsin during the 80's >> and 90's that did do core mat repair. Yes, the gal that did the work used a >> scope. She replaced cores

Re: Pro-Log M980 Programmer

On 2021-Jul-24, at 2:36 AM, DI Gerhard Kreuzer via cctalk wrote: > I own a Pro-Log M980 Prom Programmer and want to program a 2732 EProm. I > have everything needed, but how can I get the data in? > There is a serial interface, did anybody have some program for a standard > PC to handle that daa tr

Re: Programming Bipolar PROMs

On 2021-Sep-27, at 8:23 AM, Tom Hunter via cctalk wrote: > While restoring and repairing a Data General Nova 2/10 I found a bad > bipolar PROM on the CPU board. The PROM has open-collector outputs and is > organized as 32 words by 8 bits. It appears that one of the open-collector > driver transisto

Re: Programming Bipolar PROMs

On 2021-Sep-27, at 10:52 AM, Brent Hilpert via cctalk wrote: > On 2021-Sep-27, at 8:23 AM, Tom Hunter via cctalk wrote: >> While restoring and repairing a Data General Nova 2/10 I found a bad >> bipolar PROM on the CPU board. The PROM has open-collector outputs and is >> organ

Re: IBM transistor replacements

On 2021-Nov-26, at 1:52 PM, Al via cctalk wrote: > A while ago I received an IBM 3286 printer, annoyingly some of the > transistors in the printer section have been corroded. What I am having > trouble with is reading the part codes and finding a modern equivalent of > them. > There are two ty

Re: IBM transistor replacements

On 2021-Nov-27, at 11:22 AM, Gregory Beat via cctalk wrote: > > The Texas Instruments (TI) 139 is likely a 2N139 PNP (BJT) transistor, > capable of high speed switching (in that era). > > The 2N139 was originally an RCA transistor (tall cylinder) found in RCA and > GE transistor radios (455 kHz

[cctalk] Re: CDC Cyber 180/8xx PSU

On 2024Oct 12,, at 4:51 AM, hupfadekroua via cctalk wrote: > > after approx 30 years of waiting our time has come to get hands on a Cyber > 180/860a. ... > Another approach would be to substitute the old psu by modern ones, possibly > by DC-DC converters or switching powersupplies. > > Does s

[cctalk] mains stroboscope / was Re: Running DOS executables on other versions of DOSRe: Looking for Sharp PC-5000 disk drive (CE-510F or possibly MZ-80B)

The old common standard for a mains stroboscope was a neon bulb (+resistor). They are still widely available, simple and inexpensive. No, they are not very bright and need some shading or otherwise reduced ambient light, but for a tool of infrequent use...

[cctalk] Re: Try Algol 68 on Windows

On 2025Jan 13,, at 7:02 AM, Lyndon Nerenberg (VE7TFX/VE6BBM) via cctalk wrote: > > Mike Parr via cctalk writes: >> Hello all. >> Here is a link to something I wrote - brief intro to Algol 68's background, a >> nd how to run it on Windows - with a toy IDE as well. > > This triggers a fuzzy memor

[cctalk] Boot-to-BASIC / was Re: Looking for IBM System/3 BASIC book

A few weeks ago this question was raised: On 2025 May 6, at 11:20 PM, Steve Lewis via cctalk wrote: > Anyway, it leads to a question of what was the first boot-to-BASIC system? The first to come to mind was the HP-9830, it was mentioned but seemingly dismissed: > And tentatively I'm thinking

[cctalk] Re: Is there a more modern replacement for paper tape punch/reader

On 2025Jun 22,, at 11:14 PM, Bob Rosenbloom via cctalk wrote: > > There were a whole bunch of cartridge / cassette systems made to record and > play back RS-232 data. Sykes (made the 4912 cassette unit for Tektronix) , > Memodyne, Teac, Sy/MAX and many others made them. I have a Tektronix 4923

[cctalk] Re: Sad news re: Chuck Guzis

On 2025Jul 23,, at 3:13 PM, John via cctalk wrote: > > Chuck(G) passed away recently. He was highly > knowledgeable, a full-bore storage expert, and an all-around even-keeled > decent sort, and will be missed. Sad to hear. I liked hearing Chuck's inside stories and anecdotes of working in the

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