>
> Once again, I find myself in over my head debugging a power supply, this
> time an H7140 from a PDP-11/44. Here's the skinny:
That doesn't surprise me, the H7140 is one of the most complex PSUs you are
likely to come across...
> When power is applied (plugged in, breaker switch flipped to "O
>
> From a quick glance at the schematic I think that this part is related to
> the fan driving circuitry. The diodes look like some kind of protection
Yes.
> diodes which is good to have when switching inductive loads. I have really
> no idea why they have been removed. But I don't think it is
>
> The bias voltage is generated by the chopper on page three in conjunction
> with T1 and some rectifying diodes on the motherboard. Then it is feed back
> to the bias board on J2:2 to produce the 5V. (page 2)
Yes...
It's not totally obvious at first glance, but this is yet another SMPSU with
>
> I'm slowly coming to terms with the schematic but I'm not quite clear where
> these two voltages are being generated. I note from the block diagram that
> the +15 and +12 are rectified on the motherboard (backplane) -- which
> should make it GREAT fun to probe. So it looks like some careful
>
> Am I missing something? - is there anywhere in that doc that explicitly
> declares the
> association between the 2-dozen connectors, for example, that Line Supply P1
> & P2
> connect to Motherboard J5 & J4, and that Bias and Interface Board J1 & J2
> connect
> to Motherboard J7 & J6?
Not t
>
> This may be forgotten knowledge - or perhaps more likely, something that
> was never known in the first place - but are there any typical failure
> modes of ST506/412-type drives (beyond the obvious mechanical damage
> between heads and platters)?
For the genuine original ST506 ST412, etc the
> We swapped the TU56 and TU55 drives between the PDP-12 and the PDP-8/I. We
Does the TU55 work correctly on the 8/I ?
> The TU55 behaved a little better than the TU56, and sometimes would
> actually boot OS/8. We continued chasing the issue and found glitches on
> data channel 3. We have swappe
>
> Paul, if you come across any VT52s that have the built-in screen
> printer could you take some pictures please.
>
> Has anyone ever seen one? I had an idea it used a silvered-paper and
> burned it off? or am I mis-remembering.
I have one. Well, in a VT55, but that is a VT52 with a graph-plot
> The only other terminal I worked
> with that could do that was a Tektronix storage scope terminal (4010
> or 4014, IIRC). The Tek printer wasn't built-in, but it did take a
> scan of the live screen, so that was similar. The paper was
> silver-grey and I remember it coming out wet too. Everyth
>
>
> I had a little Comprint printer in the 1970s/1980s that used something
> sort of like this. The paper was aluminum coated, thus conductive. The
> head was a high voltage electrode unit that burned away the aluminum
> layer. (I can't imagine any kind of deposition technology in that
> era..
> That sounds correct. Versatec made printers that used that process, I used
> one
> (attached to the CDC 6500 at U of Illinois PLATO). Very nice for continuous
> roll
> full bitmap graphics.
The Versatec electrostatic plotters are not the same as the VT52 printer, they
are
yet another proc
[Aluminium coated paper printers]
> Even Radio Shack had one of those! But not for long. Crumpling the paper
How did the original TRS-80 screen printer work -- the one that plugged into
the
expanison bus and read out video RAM?
The 'Quick Print II' (or some very similar name) was a Radio Sha
[ASR33]
> This is a very delicate mechanical device. In spite of the fabulous shipping
> crate, the bolts
> installed to secure the printer, the shipping guys let us down. The thing
> had very rough
> handling, sheared off the shipping bolts, the printer was totally shook up
> and Wayne and
> Also for reading in paper tape, a high speed punch and paper tape reader
> is often wanted.
Yes, IMHO the ASR33 reader is an interesting thing to have, but it's only
10cps, and it is not kind to the tapes. A good capstan-fed optical
paper tape reader will do between 300 and 1000cps [1] and will
> Yes, I had a bunch of Versatec 1200A's with the Tektronix
> hard copy feature. the Versatec was the greatest graphics
> printer until laser printers came out, then they became
> instant boat anchors. Here's the process.
Only in the sense that a PDP11, or a VAX, or a PERQ, or
a is a boatanc
[Versatec paper feed motors]
> Yes, absolutely, on the Versatec 1200A. I put those motors
> in a milling machine. Big, round case stepper motors, with
> a ghastly resistor-transistor drive.
You've got me worried now...
I have V80. Actually, it's ICL-badged, and has a GPIB adapter board at th
> But, if you mean 74-series logic in general, I think so. Sometime
> within a year or so of '78, I was working with the stuff, and it was as
> an undergrad, so I doubt I would have been working with just-released
> logic.
74xxx logic dates from the late 1960s. There are plenty of production mac
> "Motherboard" was around then, although Burroughs might not have used it.
> Burroughs might very well have been more inclined to call it "backplane".
I generally use the term 'motherboard' for the sort of thing you find in an
IBM5150 or Apple ][ -- that is a board with a lot of electronics on i
> Half density? I vaguely remember an RK05 style drive at half the density.
> RK02? Or am I mixing it up with RP02 vs. > RP03?
No, you're right. The RK02 is the low-density drive (actually a Diablo model
30), the RK03 being the high
density model. The RK05 has the same bit density (heck the
> > I had another go today, but I fail to see how you managed to pry this
> > thing apart without causing much more damage than appears in your photo.
> > What kind of tool did you use?
>
> My usual technique to deal with these sort of brick and wall-wart PSUs
> that are glued together is to car
>
> So, does anyone know what the first such "farm" slang term was, and when
> and where it originated? And how about other terms with "farm" in them?
> (I came across a new one the other day, but of course I've forgotten it
> now.)
Not likely to be used much now (well, not outside members of thi
>
> I seem to recall reading or hearing a very long time ago that where a
> printer has not been fired up for eons that the pins can be stuck in the
> print head (e.g. by old ink drying out) and cause damage (e.g. bend pins)
> when it tries to print.
A word of warning. Unless you really know what
[VT100, etc, monitor PCB]
> Is that true of the vt102 as well?
I don't think I've ever worked on a VT102, but the same video monitor boards
turn up
in the VT100, VT105 and VT101 (at least). There are at least 3 different types,
at least
2 made by Ball Brothers. From what I remember the 2 Ball B
>
> > The VT101,02,31, and 32 are the same, as are the VT100, 105, and 125.
>
> If you say they are the same, can you turn a VT101 into a VT102?
I don't think there was an official way to do it (from what I remember the
VT101 was
sold as a 'closed' terminal (maybe replace the logic board), but
> The way I remember it is that the VT100 comes in several configurations (for
> example AVO or
> not) and you can field modify it from one to another.
>
> On the other hand, the VT101 and VT102 are fixed configs (that is, not
> intended to be field
> upgradable), roughly matching the base and A
>
> > The 2190 does not, and it fails in precisely the same way I've personally
> > seen three or four
> > other Maxtor drives of the same era fail: It spins up fine, but when it
> > goes to load the heads,
> > it sounds like the voice coil positioner for the heads is "screaming" -- it
> > emi
> The UK is full of small companies making and repairing all kinds of past
> products.
>
> For example the MGB GT (a much loved British sports car). The factory
> stopped making them in the early 1980's
> However a few guys bought the press tools and have been turning out two
> or three body shel
>
> That's pretty much what I figured. I took a closer look at one of the
> other dead XT2190s I have that I'd opened up to inspect awhile back and
> there are a few ICs surface-mounted to the flat ribbon cable running to
> the head assembly. I suppose it's likely that one of these has failed,
>
> I'm wondering what I can put between the two to keep the cable from
> disconnecting from the adapter. Some searches seem to indicate I want
> some 4x40 (or 4-40) female-female (coupling) nuts; does this seem
> correct?
The normal thread for the jackscrews on a D connector is indeed 4-40 UNC.
Th
> Further digging into available eproms that the programmer can read reveals
> it CAN read 2532s, specifically the MCM2532 which the datasheet tells me has
> the same pinout as the 2332. I still get "reverse insertion error" so I'm
> guessing my PROMs are toast.
As others have said, normally when
>
> For reasons too abstruse to explain in detail I'm on the lookout for
> terminals that are, physically, really small - especially serial and
> coax 3270, and possibly twinax 5250.
>
> Yes you could do things with small laptops and PDAs with PCMCIA cards
> and adapters and software - I know a gu
[HP Palmtops, 95LX etc]
> Oh those look pretty good; I love the terminal emulator in ROM;
> doesn't even need an OS, switch it on and it works; that's one of the
> things I'm after. Shame about the rather nasty looking monochrome LCD
Actually, there is an OS -- MS-DOS -- and it's in ROM too. Along
>
> On the HP 2100 series machines (and possibly 1000s?) - those top of
> the card connectors - are they the 2 x 24 contact on 0.156" centers
> types?
In most cases yes. There are some which are obviously 0.1" pitch.
-tony
[HD 3.5" disks and the density-select hole]
> Of course, on a DD-only drive, the drive is blind to the extra hole.
Not always! The original Sony full-height drives (the 600rm ones) have a
disk-inserted sensor positioned exactly where that hole is. So if you insert
an HD disk the drive doesn't
>
> Yes, the Sony OA-D32 drives. Single-sided 600 RPM. One *could* argue,
> that, given the data rate, it's already "high density" (of a sort). I
I would say it's normal double density (the spacing of the flux transitions
on the disk is the same as on a PC 720K disk) but a high data rate due
t
> My favorite low tech dummy load is the one my father came up with: a couple
> of
> resistors (carbon composite is best, carbon film or metal film will do), 1-2
> watt size,
> in a jar filled with water. Works just fine for 100 watts or so, and is
> useable not just
> for power supplies bu
> > And my advice, sadly learnt and forgotten quite a few times, always after
> > drilling a critical part:
> >
> > CLAMP THE JOB DOWN!
> +1 on Steven's advice, having learned this lesson the hard-way.
I'll second (third? nth?) that!
I was once told that the majority
>
> ROM problems aside does anyone know of a way I can test the actual CRT?
By 'CRT' I assume you mean the evacuated glass thing. The term is alas also
misused to mean 'monitor'
[...]
> Back when I was fixing my broken TRS80s I could use the CRT from a B&W TV,
> is there anything oddball about
> experience. An 'UP ARROW' means nothing, nor does 'FRAGILE'
I thought 'Fragile' meant 'Use this package for playing American Football'
This it not a new problem, it probably pre-dates the ASR33. Flanders and Swann
(think of them as being the British equivalent of Tom Lehrer) said
The new way
[RL cables]
> AFAIK that cable is purely a bus (i.e. no radial per-drive wires), so you
> should just be able to run it to the second connector, no issue. However,
> I'm too lazy to check to make sure that's absolutely 100% accurate. :-)
It is just a bus. The internal drive cable is just a lenght
>
> When you had machines with an RL-drive "internal", you normally did not
> use a cab kit. That was for external drives. The same is true for all
> other DEC drives I know as well. I've certainly seen direct cabling
> internally for SDI drives as well as external cabling for RX50 and TK50.
The
>
> Hi Guys
> Sitting here doing the overlays for the 8/e silk screen run.
> I had a thought. Including all makes of computer old and new.
> What about a front panel with lights and switches for systems
> that never had one and could have done with one?
> Which computer would you nominat
>
> Hi Tony
> I seem to remember, certainly in OEM land there were dev.
> systems with front panels and production systems without.
> In other words the front panel was option and could be fitted.
Sure. The PDP8/f and PDP8/m are the well-known example. Many of the
Philips P800s had o
>
> Yes much as I thought. What about S100 systems?
> Many did have lamps and switches but I can think of a couple that didn't .
> Northstar Horizon for one and Cromenco also.
If you have a machine that allows for other devices to become a bus master and
access memory and I/O devices (S100 does t
> One problem with a front panel on an S100 machine - or any
> microprocessor-based
> machine - is getting access to the program counter so you can tell it to
> start running
> at some arbitrary address. The Altair/IMSAI panels resolved this with a hack,
> jamming
> a jump instruction into th
>
> If it has a transistor at the primary side, and a high frequency transformer,
> it's a switching supply.
> Those want a load, usually. Especially the older ones.
If there are large-ish electrolytics (100's of uF) with a voltage rating around
200V and no reason to
believe that there is a
> That said, it's possible that there may be an auxiliary linear regulator in
> there. That's common
> for additional outputs with modest current needs, especially in older
> designs where the
> switching circuitry takes a lot of individual components. A TO-3 can isn't
> what I would expect
>
> You mentioned DEC PSUs, this one is actually made by ASTEC. I will use a
Firstly, every Astec PSU I've seen has been a swticher. They probably did make
linear PSUs, but not common...
Secodnly, it may have been made to a DEC design (rather than just a
specification).
I believe you replace
[Chopper transistor]
> This one is a D905.
I assume that's a 2SD905 (the '2S' is often left off the package). From the data
I've seen that certainly could be used as a chopper transistor.
-tony
>
> Then you've not come across the ones in TK50Z desktop cases (and a few
> other things). They don't like operating without a minimum load,
No, probably not. Actually I may have one somewhere, but have never had to
repair it, so have never run it without a load.
Thanks for the warning though!
> > I've been trying for the past week to verify that telephony on my teletype
> > machine (model 33) is functioning properly but the biggest hurdle I am
[...]
> Is yours ASCII or "Baudot"? (there are some issues of the correct name for
> that)
If it's a model 33 it has to be ASCII. The 'Baudot
>
> I am developing (it is under construction to add additional features that I
> need) an
> Arduino-based central office simulator that will allow two devices to connect
> to each
> other as though connected by POTS lines. I began developing it to simplify
> work in the
> shop on a variety of
> The Baudot thing sure brings back some memories. I still recall hooking
> teletype's up thru KW-7 boxes, and performing ryryryryryryryryr test.
>
> I don't recall enough of the specifics, but it was either
>
> Y = 10101
> R = 01010
>
> or reversed.
Ah yes... One of the classic tests for pr
>
> Hi, all: I recently bought a PDP-11/45 [well, a /55, to be technical; the /45,
> /50 and /55 are completely identical except for i) the memory options
> installed at purchase, and ii) the printing on the front console :-], but
> alas, when I looked closely, it is missing both upper and lower C
[2 'Interface and Timing M7706 cards in an RK07]
> The existence of two separate wire list pages in the schematic, and a
> quick look at the M7706 diagram output signals suggests that this would
> *not* work - that the output lines of the two M7706 cards are wired
> together on a single-port drive
>
> They were for video in and out. You could sync the VT100 to a feed of
> mono video and the overlaid
> picture would appear on the screen and at the video out connector.
Actually, I beleive (confirmed by the VT100 tech manual and schematics)
that you have to sync the external video to the VT1
>
> I remember joining DEC in early October 1973. At the time I was working
> for a small local company called Newbury Labs.
When I was an undergraduate at Cambridge University (1985-1988) they were
still using (somewhat later) Newbury terminals on the mainframe. Due to the
metal cases they wer
> All Centronics ports have 8 bits going one way, and 4 "handshake" bits
> going the other way.
That's a very PC-centric statement for you, and I am not convinced it's even
true
on IBM PCs and compatibles!
There are plenty of machines that have 7 or 8 data bits output, automatic
strobe
when
>
> http://terrysrubberrollers.com/
>
> Terry has rebuilt about a dozen rollers for me over the past 2 years.
> You'll need to remove the roller and send it in to him with a money order
> (he doesn't take checks or credit cards), but he'll do a fantastic job for
> about $40-50 per roller.
Any sug
> For that many rollers and that amount of money, personally I would spend it
> on a small
> lathe such as a Unimat, Taig or Sherline (I'm a Unimat fanatic myself, I love
> 'em. A
> vastly underrated machine if there ever was one).
Actually I have a Myford Super 7...
> For sources of hard rub
> > COMBINE THEM THEN JUST ADD TWO LETTERS AND A DASH AS THUS
> > CC-
>
> SOMEONE SUGGESTING THIS AND USING CAPITALS ONLY PROVES TO BE A MAIL NOOB
> ;-)
Or is using a Model 33 ASR (or KSR) :-)
-tony
> My reading of the Qbus spec is that P OK and DC OK are active high. That
> diagram
They are, for a very logical reason. Remember you can wire-AND open-collector
signals
-- that is link them together so that any driver can pull the line low and the
line will
only be high if all driver transist
> > The RH11 do DMA, just like all other disk controllers I know of.
>
> IIRC, the RX11/RX211 (Unibus) and RXV11/RXV21 (Qbus) don't do DMA.
The RX11/RXV11 don't do DMA, but the RX211 and RXV21 do, I think
-tony
>
> Hi folks,
>
> I've begun repairing my PDP 11/40 and have tracked down the first major issue
> to the H745 (-15v) regulator.
Before you dive into the brick (sounds painful!) check that the +15V DC input
is present and correct. Unlike
the +5V units (H744, etc) the H745 needs both the 20V AC
> There is a pdp 11 troubleshooting guide on Bitsavers that covers the h742
> powersupply and regulators 744. 745, 754. Assuming that is what you have.
>
> They're all tough to work on especially the regulators but I agree with
> Tony that you need to lock down the main suppl first.
I am not sur
[H745 regulator]
> Tough-sh to physically work on/test. These are not made for field service
> IMHO, just swap out part.
If you make up the extension lead so you can run it outside the PSU chassis
then
it is very easy to work on. The PCB is exposed on one side of the brick and as
I said it's a
>
> Anyone have a source to purchase the tape to repair a papertape, or a kit
> such as what they have here:
>
> http://physicsmuseum.uq.edu.au/paper-tape-repair-tool
I have actually bought such hand punching kits in charity shops (thrift stores)
in
the UK -- but about 15 years ago. No, the one
>
> So I owend up said I wired it. The answer came back oh if its a
> personal job it gets top prioriy.
> You can use what ever equipment you want and take whatever components
> you need.
> I often borrowed a scope ove the week end.
I know a chap who runs a small electronics company. He actively
> punches and two keyboardless golfball typewriters. I have forgotten
> exactly what types they were. I think the punch said something like
> BPRE on it and the readers did not match the rest of the system being
Probably BRPE (normally pronounced 'Burpee') which is a high speed
(something like 1
> NOTE: I will pay a generous price for a few inches of papertape repair tape
> if anyone has any! I am located in Landenberg, PA USAContact me
> privately if you can help.
The official splicing tape I've seen is in little squares with all holes
punched
(probably covers 9 or 10 characters o
> Hi Tony
> Did you say Data Dynamics? I certainly knew them. I used
> to sell them LA36 print mechs.
Yes, almost certainly the same company. They sold several teleprinters
based on the Teletype Model 33. Same mechanics, but IMHO a nicer (all
metal) case and different electronics.
> The VT50 comes (according to the peripherals handbook) with a standard 20 mA
> interface, optional RS232 interface. So it sounds like it would be a matter
> of finding
> where the 20 mA connector on the VT50 is, and plugging into that.
>
> Interestingly enough, the VT52 is listed as supporti
>
> Circumference and Diameter are linked by the constant Pi and therefore
> are an entity.
> Its a little more complex with a rubber wheel and its indented path.
Indeed. And that may even depend on the type of 'rubber' used and how
it deforms when pressed against the cartridge drive wheel. Remem
> Mathematically, circumference is PI times diameter or 3.14159. times
> the diameter.
Doesn't that depend on the defintion of 'distance' in that a circle is the
set of points in a plane equidistant from a given fixed point? Using the
'normal' definition of distance you do indeed get the ab
>
> This is the picture..
> https://www.flickr.com/photos/hp-fix/9452805294/in/album-72157634959418702/
> I'm using a special kind of hose, which is precisely made.
OK, what is it called, who makes it, and where can you buy it?
-tony
>
> I tried measuring a whole bunch of circles, and I can't find any rational
> reason why dividing the circumference by the diameter never came out even!
> :-)
Groan!
-tony
> Hi
> Well it certainly works for you Rik.
> I dont speak Dutch and its not clear exactly which of the products you
> refer to.
> The end of hub appears to have been turned on a lathe.
> So if you speak Dutch and have a nice big lathe in your shed you can fix
> your TU58
Surely you don't n
>
> Hi Tony
> Thats interesting I had thought about a model makers lathe.
> I have a pillar drill and the usual set of tools.
I am darn glad I asked for a lathe instead of a car (and driving lessons) when
my late father offered to buy me the latter. I still can't drive, but I don't
>
> TU58 's is ready to test. I tried it in a spare serial port on a VS 3100.
> Result nothing. I suspect the port is 423 and the tu58 232.
Actually the TU58 serial port has the differential driver and receivers used
on the later serial ports. It should talk to DECs version of RS423 with no
prob
> >
> >> TU58 's is ready to test. I tried it in a spare serial port on a VS 3100.
> >> Result nothing. I suspect the port is 423 and the tu58 232.
> >
> > Actually the TU58 serial port has the differential driver and receivers used
> > on the later serial ports. It should talk to DECs version of R
>
>
> There seems to be a spike on the 12V supply, surely that isn't good, even if
> it doesn't affect the memory?
Often a spike on a particular output of an SMPSU is caused by a high ESR
capacitor
on that output. It's worth checking them.
FWIW, old DRAMs, up to about 16Kbit size, often used +1
>
> The Evotek 5000 series is a bog-standard ST-506/ST-412 "MFM" interface.
> OEM manual is on Manx:
>
> http://manx.classiccmp.org/mirror/harte/Evotek/ET-5000%20Family%20OEM%20Manual.pdf
>
> Back in 1983 I had an opportunity to play with one. Pretty interesting,
> but very expensive, as I rec
>
> I rescued one for VCFederation museum two years ago.
> http://vintagecomputer.net/perq/
> I was just looking at it this weekend. It needs a keyboard and mouse I
> believe. I remember there was a guy in Texas who had a few, never heard
> the full story though.
That's a PERQ 1 (or 1a, the diff
>
> Tony - thanks I passed the info along to our club.
Some years ago I made some notes on the insides of my PERQ1 keyboard. Hopefully
they will surface again when I get round to unpacking the rest of my books
(after the
house move..). If not then I can probably work it all out again, I do certa
> The Kriz tablet definitely existed, I have half of one (it's the "mouse"
> portion, it basically looks like a Hawley mouse without the ball). The
> device is supported in the Z80 code, PERQ microcode and POS software.
Are you thinking of the PERQ 2 version that had a synchronous serial interfac
> All the email clients I have are top posting get with the times you guys
I have no desire to 'get with the times' -- this is classiccmp after all.
If your mail program doesn't let you scroll to the end of a message and
start typing then it is fundametnally broken. It may not be convenient, b
>
> I've done the obvious, reseating socketed ICs, checking the +12V and +5
> rails, and checking the on-board CPU reset line. Does anyone have any tips
> for what's best to try next?
Didn't at least some versions use 2114 RAM chips? If so, then check/change
those first
-tony
>
> Yes, I've certainly seen that on the schematics, and was considering them
> as a likely failure too - after opening cases though, my drives all seem to
> have a single larger SRAM (even the Rev A board, so that's presumably "Rev
> A of the type that doesn't use 2114's" :-)
Yes, later versions
> Can anyone give me a clue as to the purpose and pinouts of an Allen
> Bradley 314B102??!!
First guess, it's not really an IC, it's a resistor array. Either separate
resistors
going across the chip or resistors all commoned to the highest numbered
pin (which may well be +5V).
I would secondly
Some more random thoughts
>
> Of the above 10 pins, 11, 13, 22 & 23 are high at power-up (printer
> NOT connected to any interface). The only pin with known function is
> 19, which is 'paper out'; if I toggle the paper out switch I can see
> it going high and low.
Well, 19 could be a general
>
> I don't think any of the single-disk CBM drives used 2114s (but I
> agree - those are favorite suspects when present). I'm pretty sure
> all the units I've worked on have 6116-type 2K SRAMs or perhaps 6264s.
> I'd have to go back and check parts lists, but the older dual-drive
> units might h
>
> I guessed that might be the case... any suggestions for what were
> common pinouts and signals used? I can analyze 'backwards', testing
There were just about as many parallel interface versions as devices
that used them back then. Nothing 'common' really...
The idea of 7 or 8 data lines,
>
> > Well, 19 could be a general printer-ready pin in that if the paper runs
> > out it would say the printer is not ready for another character but
> > it might well also be put to the not-ready state when the printer
> > was printing the current character. Seen that before.
>
> Maybe, but Sele
[Printer's Ready signal]
> > Why not? It's all the host really needs to know -- can I send
> > another character or not.
>
> Well...it can be very nice for the host to report "out of paper"
> differently from "paper jam" differently from "motor or position
> encoder failure" differently from "fa
I suspect the answer is no, but before I spend a few afternoons tracing out the
diagrams,
does anyone have a schematic or (real) service manual for the Diablo/Xerox 3000
computer, in particular the MRPRO CPU board.
This is a 1980s all-in-one business desktop computer with 2 internal 8" drives.
B
>
> Tony, good advice but probably more work than I'm inclined to put in.
What I have suggested would take about 10 minutes tops. It has probably
taken me longer to type this message than it would take me to figure
that out.
> As you said there were many interfaces with different standards -
> d
>
> > This is a 1980s all-in-one business desktop computer with 2 internal
> > 8" drives. Based on an 8085 CPU.
>
> Actually, a 70s micro--I used to work with the guys who did a lot of the
Right. I was going by the date codes on the ICs, etc. Makes sense it
could be earlier.
They should have c
>
> We were moving, and my Spousal Unit convinced me to toss things I hadn't
> touched in a while - including my Intercept Jr. with the 32K battery-backed
> RAM card, and an old-style acoustic coupler modem.Now that I'm
> considering a major move again (after my daughter goes off to college, i
>
> > I have one that was mangled in the house-move (the movers decided to cut
> > the keyboard
> > cable for me).
>
> Wow, did you get any compensation?
You are joking, right? Their 'terms and conditions' mean you had to claim within
7 days of the move. I don;t know anybody who could inspect e
> In my experience, the type of socket you used is quite unreliable and
> will tend to develop bad contacts. There is a reason they are cheap... I
> would use a turned pin type socket instead, e g an Augat socket. They
> will not let you down. More expensive, but considering the work involved
> in
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