[cctalk] Re: IBM RT Graphics

[emanuel stiebler via cctalk]

On 2023-06-08 08:20, Santo Nucifora wrote:

Looking back, I did buy one from Digikey but it was not the right one.

I bought mine from this ebay auction: 
https://www.ebay.com/itm/171649843131 
  Specifically, the "D-SUB 3W3 
Male" item.  I did not install the three metal coax covers that come 
with it.  The end looks like this: 
https://vintagecomputer.ca/wp-content/uploads/2023/06/IBM_RT_3W3_end.jpg 



Hope this helps.
Santo


Hello Santo, looks good, just ordered some.
THANKS!

[cctalk] Re: Looking for information on Data General 602X magtape drive

[Sellam Abraham via cctalk]

On Thu, Jun 8, 2023 at 2:53 PM Bjoren Davis via cctalk <
cctalk@classiccmp.org> wrote:

>
> When it was decomissioned it was just cut out, so it's missing its
> chassis, hinges, controller board, power supplies, vacuum blower, vacuum
> pressure limit switches, etc. The cables to the heads are just cut (no
> connectors).


So in other words, everything but the tape transport?

My goal is to replace all of the missing controller parts with some SOC
> boards (e.g., a Teensy 4.1), ultimately to be able to use this drive to
> read and write tapes.  I'd love to reuse the console board as it is.
>

Good luck.  And I mean that sincerely.  If starting with what (little) you
have you end up with a working tape drive it will be quite the
accomplishment.

Sellam

[cctalk] Looking for information on Data General 602X magtape drive

[Bjoren Davis via cctalk]

Hello CCtalk,

I recently bought the mortal remains of a Data General 602X magtape 
drive on craigslist.


Apparently it had been stored outside.  When I got it it had mudwasp 
nests and mud all over it and everything that could rust had.


When it was decomissioned it was just cut out, so it's missing its 
chassis, hinges, controller board, power supplies, vacuum blower, vacuum 
pressure limit switches, etc. The cables to the heads are just cut (no 
connectors).


But boy does it look cool, and it *does* have all three of its transport 
motors and its console PCB.


There's very little identifying information on the drive.  The front of 
the drive has a label "9 TRACK 800 BPI".  The console PCB says 
"COPYRIGHT © 1973 BY DATA GENERAL CORP" "CONTROL BOARD FOR 75 I.P.S. 
DRIVE   DGC NOVA 107-000275-17 /16" and has a sticker on the back 
"DRAWING NO.  REV.  005-005-525-02 005-001-743-11".  The date codes 
on the few chips I can read place it from 1976.  I think all of this 
adds up to this being a model 6021 or 6023.


I've been slowly disassembling, cleaning, and repairing it.  The DG 
documentation at bitsavers is really good, but, sadly, the schematics 
are not available there.


Does anyone have such schematics?  I'm especially interested in the 
analog portion that connects to the heads, the connection to the BOT/EOT 
sensor, and a schematic for the console board I actually do have.


My goal is to replace all of the missing controller parts with some SOC 
boards (e.g., a Teensy 4.1), ultimately to be able to use this drive to 
read and write tapes.  I'd love to reuse the console board as it is.  
I've already replaced the vacuum blower with a $30 Bosch vacuum cleaner 
I also bought on craigslist.


Thanks.

--Bjoren

[cctalk] Re: First non-IBM PC-DOS Compatible PC

[Fred Cisin via cctalk]

Then, Toshib NMRI in Silicon Valley needed to be able to handle
Toshiba 80 track format disks for communication with home office, so
I gave the T300s to them.



On Thu, 8 Jun 2023, Yeechang Lee via cctalk wrote:

So a Toshiba office did not have computer equipment compatible with what its 
headquarters used?


Instead, they could have bought a copy of 22Disk, XenoCopy, or Uniform.
But the two T300s were cheaper.

[cctalk] Re: First non-IBM PC-DOS Compatible PC

[Fred Cisin via cctalk]

Then, Toshib NMRI in Silicon Valley needed to be able to handle
Toshiba 80 track format disks for communication with home office, so
I gave the T300s to them.


On Thu, 8 Jun 2023, Yeechang Lee via cctalk wrote:

So a Toshiba office did not have computer equipment compatible with what its 
headquarters used?


Yes
The USA NMRI group had assumed that their Japanese counterparts would be 
using PC formats, and apparently that was often/usually the case.  They 
could have asked the home office to send them machine(s), but I had some 
handy.  A friend was doing some engineering consulting for them, and was 
thus able to solve the [very minor] problem immediately.  I think that it 
was intended to be a short-term loan while getting machine(s) shipped, 
but I told them to keep them.


--
Grumpy Ol' Fred ci...@xenosoft.com

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

This wasn't a large IBM lineprinter and I'm pretty sure it was 1" tape, but
it may well have been inspired by those machines.  It would likely have
been used with custom fanfold paper for invoices, cheques etc. - certainly
the same sort of customer-specific those machines dealt with, but for the
small office. A predecessor to the PC.

On Thu, Jun 8, 2023 at 7:13 PM Paul Koning  wrote:

>
>
> > On Jun 8, 2023, at 1:18 PM, Adrian Godwin  wrote:
> >
> > ...
> > I've seen mylar tape used in a tiny loop where it controlled the
> movements of a printer platen. I don't recall now whether it was used for
> horizontal or vertical space - my recollection was the latter but it was a
> long time ago.
> >
> > I don't know why it wasn't controlled by ASCII - a good bit of the
> character set is dedicated to print head control. I think a different tape
> had to be installed to match the program that was being run. The machine
> was used for accountancy in about 1975, It was a bit like a large LA120
> (but included the calculating part) and made by the french Logabax company.
>
> Many line printers used a "VFD" tape (vertical format definition?) which
> is a 12-channel tape with one row per line on the paper.  The idea was that
> you could tell the printer "skip to channel N" and it would advance the
> paper until a hole in that channel was seen.  By convention, channel 1
> marks the top of the page, and in fact typically that position was punched
> all the way across so a skip to an "unused" channel would not produce
> runaway paper.  Channels other than 1 would be used for custom forms, where
> it would save time to skip across part of the form rather than advancing
> line by line to the desired spot.
>
> If you only ever used regular size paper this stuff wouldn't be obvious,
> but an operator who had to handle other forms, like checks or label stock
> or anything else that wasn't just plain 60/66 line pages, would have to
> change the paper along with the matching format tape.  Some printers had
> small local memories that could be downloaded with the form definition tape
> data, avoiding the need for the operator to switch the tape manually.
>
> paul
>
>

[cctalk] Re: First non-IBM PC-DOS Compatible PC

[Yeechang Lee via cctalk]

Fred Cisin says:
> Then, Toshib NMRI in Silicon Valley needed to be able to handle
> Toshiba 80 track format disks for communication with home office, so
> I gave the T300s to them.

So a Toshiba office did not have computer equipment compatible with what its 
headquarters used?

-- 
geo:37.78,-122.416667

[cctalk] Re: Source for NEW (unused) punch tape

[Paul Koning via cctalk]

> On Jun 8, 2023, at 1:18 PM, Adrian Godwin  wrote:
> 
> ...
> I've seen mylar tape used in a tiny loop where it controlled the movements of 
> a printer platen. I don't recall now whether it was used for horizontal or 
> vertical space - my recollection was the latter but it was a long time ago. 
> 
> I don't know why it wasn't controlled by ASCII - a good bit of the character 
> set is dedicated to print head control. I think a different tape had to be 
> installed to match the program that was being run. The machine was used for 
> accountancy in about 1975, It was a bit like a large LA120 (but included the 
> calculating part) and made by the french Logabax company.

Many line printers used a "VFD" tape (vertical format definition?) which is a 
12-channel tape with one row per line on the paper.  The idea was that you 
could tell the printer "skip to channel N" and it would advance the paper until 
a hole in that channel was seen.  By convention, channel 1 marks the top of the 
page, and in fact typically that position was punched all the way across so a 
skip to an "unused" channel would not produce runaway paper.  Channels other 
than 1 would be used for custom forms, where it would save time to skip across 
part of the form rather than advancing line by line to the desired spot.

If you only ever used regular size paper this stuff wouldn't be obvious, but an 
operator who had to handle other forms, like checks or label stock or anything 
else that wasn't just plain 60/66 line pages, would have to change the paper 
along with the matching format tape.  Some printers had small local memories 
that could be downloaded with the form definition tape data, avoiding the need 
for the operator to switch the tape manually.

paul

[cctalk] Re: Source for NEW (unused) punch tape

[ED SHARPE via cctalk]

Pun h makes all  holesEd#         SMECC 

Sent from AOL on Android 
 
  On Thu, Jun 8, 2023 at 9:21 AM, Adrian Godwin via 
cctalk wrote:   A slitter is a wide paper feed system 
with sharp-edged pulleys over which
it passes. There are quite a few videos of this on youtube, it's
surprisingly well documented. Because slitter manufacturers are selling to
mom-and-pop outfits.

I think the tape is supplied unpunched and the tape punch makes both feed
holes and data holes. I could be wrong.


On Thu, Jun 8, 2023 at 5:10 PM Chuck Guzis via cctalk 
wrote:

> On 6/8/23 08:52, Adrian Godwin via cctalk wrote:
> > I think paper-slitters are pretty common. That is to say, if you go to
> > anyone manufacturing adding machine rolls they will have the capability
> to
> > make custom widths in rather small job lots. It's an industry comparable
> > with printing (and often combined, for when till rolls with custom
> printing
> > is desired). So it may be that although paper tape is no longer available
> > from computer stationary suppliers, it can very easily be made in quite
> > small MOQs.
>
> How does one, using modern equipment, both slit and perforate (feed
> holes) blank tape?  Color me curious.
>
> --Chuck
>
  

[cctalk] Re: Source for NEW (unused) punch tape

[Nigel Johnson Ham via cctalk]

IIRC the Centronics 101 printers did this.   It was for vertical spacing 
- you could put different loops in for different form lengths.


I used to service them (mostly replacing heads) but never operated :-)

cheers,

Nigel



On 2023-06-08 13:18, Adrian Godwin via cctalk wrote:

On Thu, Jun 8, 2023 at 6:01 PM Paul Koning  wrote:


I wonder if mylar tape for punching could be found, or made.  That was
seen occasionally, for applications where a tape needed to be read many
times.  An OS binary tape might want that.  I also remember seeing it on a
machine in my father's lab, where it contained correction factors for a
piece of precision machinery.


I've seen mylar tape used in a tiny loop where it controlled the movements
of a printer platen. I don't recall now whether it was used for horizontal
or vertical space - my recollection was the latter but it was a long time
ago.

I don't know why it wasn't controlled by ASCII - a good bit of the
character set is dedicated to print head control. I think a different tape
had to be installed to match the program that was being run. The machine
was used for accountancy in about 1975, It was a bit like a large LA120
(but included the calculating part) and made by the french Logabax company.

I worked in a manufacturing plant around 1985 where the (new)
pick-and-place machine was controlled by a paper tape. The tape was punched
on an ASR33 or similar. It seemed like an obsolete solution even though
only just installed. I bought a very nice surplus Facit tape punch from a
classified ad in Wireless World, built a serial to parallel interface and
allowed the machine programmer to create the source on a word processor
(which was our manufactured product) instead.


--
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype:  TILBURY2591

[cctalk] Re: Source for NEW (unused) punch tape

[Chuck Guzis via cctalk]

On 6/8/23 10:18, Adrian Godwin via cctalk wrote:

> I've seen mylar tape used in a tiny loop where it controlled the movements
> of a printer platen. I don't recall now whether it was used for horizontal
> or vertical space - my recollection was the latter but it was a long time
> ago.

The 12-channel tape used on line printers (e.g. IBM 1403), was, IIRC,
Mylar-coated.  Much wider than regular 1" paper tape, however.

--Chuck

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

On Thu, Jun 8, 2023 at 6:01 PM Paul Koning  wrote:

> I wonder if mylar tape for punching could be found, or made.  That was
> seen occasionally, for applications where a tape needed to be read many
> times.  An OS binary tape might want that.  I also remember seeing it on a
> machine in my father's lab, where it contained correction factors for a
> piece of precision machinery.
>

I've seen mylar tape used in a tiny loop where it controlled the movements
of a printer platen. I don't recall now whether it was used for horizontal
or vertical space - my recollection was the latter but it was a long time
ago.

I don't know why it wasn't controlled by ASCII - a good bit of the
character set is dedicated to print head control. I think a different tape
had to be installed to match the program that was being run. The machine
was used for accountancy in about 1975, It was a bit like a large LA120
(but included the calculating part) and made by the french Logabax company.

I worked in a manufacturing plant around 1985 where the (new)
pick-and-place machine was controlled by a paper tape. The tape was punched
on an ASR33 or similar. It seemed like an obsolete solution even though
only just installed. I bought a very nice surplus Facit tape punch from a
classified ad in Wireless World, built a serial to parallel interface and
allowed the machine programmer to create the source on a word processor
(which was our manufactured product) instead.

[cctalk] Re: Source for NEW (unused) punch tape

[Paul Koning via cctalk]

> On Jun 8, 2023, at 1:05 PM, Chuck Guzis via cctalk  
> wrote:
> 
> On 6/8/23 09:51, Martin Bishop via cctalk wrote:
>> The puches I have knowledge of do all 9 holes.
>> Similarly, the blank tape stock (of my acquaintance) is unpunched.
> 
> That would figure in why I occasionally see tapes with
> irregularly-spaced feed holes.   That clears that mystery up.

Ouch, that would be a case of a badly maintained punch.  If you feed such tapes 
into a reader that uses a sprocket feed wheel you'd have trouble.  If it's an 
optical reader with a plain wheel (friction feed) it will probably work ok if 
the spacing errors are not so bad that they throw off the timing.

> Instead of plain paper tape, is there any objection to Mylar- or
> Mylar-coated tape?  I note that several manufacturers recommend it.

I just did a Google search for "cnc punch tape" and an ebay sale for new mylar 
tape (1000 foot rolls) popped up.  That should work great if your punch can 
punch it reliably.  I'm not sure if all of them do.  Mylar tape is much 
stronger, so it's great for tapes that are read many times, but that's probably 
not much of a consideration for modern hobby usage.  It might explain why the 
stuff shows up when you look at CNC applications, though -- between the need to 
be able to do series production, and the abuse things get in a shop floor 
setting...

paul

[cctalk] Re: Source for NEW (unused) punch tape

[Chuck Guzis via cctalk]

On 6/8/23 09:51, Martin Bishop via cctalk wrote:
> The puches I have knowledge of do all 9 holes.
> Similarly, the blank tape stock (of my acquaintance) is unpunched.

That would figure in why I occasionally see tapes with
irregularly-spaced feed holes.   That clears that mystery up.

Instead of plain paper tape, is there any objection to Mylar- or
Mylar-coated tape?  I note that several manufacturers recommend it.

--Chuck

[cctalk] Re: Source for NEW (unused) punch tape

[Paul Koning via cctalk]

> On Jun 8, 2023, at 12:21 PM, Adrian Godwin via cctalk  
> wrote:
> 
> A slitter is a wide paper feed system with sharp-edged pulleys over which
> it passes. There are quite a few videos of this on youtube, it's
> surprisingly well documented. Because slitter manufacturers are selling to
> mom-and-pop outfits.
> 
> I think the tape is supplied unpunched and the tape punch makes both feed
> holes and data holes. I could be wrong.

That's right.

Getting tape made to order might come in handy if you want odd sizes.  5 and 8 
channel tape is fairly common, but there was also 6 and 7 channel tape (in 
widths specific to those types) which is far less common.  I haven't seen 6 
channel tape since the 1970s when it was still used in typesetting equipment, 
and I never heard of 7 channel tape until recently (it was used on some 1960s 
era machines).

I wonder if mylar tape for punching could be found, or made.  That was seen 
occasionally, for applications where a tape needed to be read many times.  An 
OS binary tape might want that.  I also remember seeing it on a machine in my 
father's lab, where it contained correction factors for a piece of precision 
machinery.  There seem to be two types of that tape: one is just mylar, shiny, 
often metallized to make it reliably opaque for optical readers.  The other is 
a paper/mylar/paper sandwich that feels like plain paper tape but is much 
stronger.  I'm not sure where that was used.  Perhaps in machines that liked 
oil, such as Teletype machinery.

paul

[cctalk] Re: Source for NEW (unused) punch tape

[Travis Pierce via cctalk]

I have a few saved searches on eBay.   I think these are not a bad price.
https://www.ebay.com/itm/392994905002

My GNT4601 punches the guide holes and uses unperforated tape too.

On Thu, Jun 8, 2023 at 10:34 AM William Sudbrink via cctalk <
cctalk@classiccmp.org> wrote:

> The punch (on an ASR33 anyway) punches the feed (center) holes.  All the
> rolls I have are completely unperforated.
>
> -Original Message-
> From: Chuck Guzis via cctalk [mailto:cctalk@classiccmp.org]
> Sent: Thursday, June 08, 2023 12:10 PM
> To: Adrian Godwin via cctalk 
> Cc: Chuck Guzis 
> Subject: [cctalk] Re: Source for NEW (unused) punch tape
>
> On 6/8/23 08:52, Adrian Godwin via cctalk wrote:
> > I think paper-slitters are pretty common. That is to say, if you go to
> > anyone manufacturing adding machine rolls they will have the
> > capability to make custom widths in rather small job lots. It's an
> > industry comparable with printing (and often combined, for when till
> > rolls with custom printing is desired). So it may be that although
> > paper tape is no longer available from computer stationary suppliers,
> > it can very easily be made in quite small MOQs.
>
> How does one, using modern equipment, both slit and perforate (feed
> holes) blank tape?  Color me curious.
>
> --Chuck
>
>
> --
> This email has been checked for viruses by Avast antivirus software.
> www.avast.com
>

[cctalk] Re: Source for NEW (unused) punch tape

[Martin Bishop via cctalk]

The puches I have knowledge of do all 9 holes.
Similarly, the blank tape stock (of my acquaintance) is unpunched.
Martin

-Original Message-
From: William Sudbrink via cctalk [mailto:cctalk@classiccmp.org] 
Sent: 08 June 2023 17:34
To: 'General Discussion: On-Topic and Off-Topic Posts' 
Cc: William Sudbrink 
Subject: [cctalk] Re: Source for NEW (unused) punch tape

The punch (on an ASR33 anyway) punches the feed (center) holes.  All the rolls 
I have are completely unperforated.

-Original Message-
From: Chuck Guzis via cctalk [mailto:cctalk@classiccmp.org]
Sent: Thursday, June 08, 2023 12:10 PM
To: Adrian Godwin via cctalk 
Cc: Chuck Guzis 
Subject: [cctalk] Re: Source for NEW (unused) punch tape

On 6/8/23 08:52, Adrian Godwin via cctalk wrote:
> I think paper-slitters are pretty common. That is to say, if you go to 
> anyone manufacturing adding machine rolls they will have the 
> capability to make custom widths in rather small job lots. It's an 
> industry comparable with printing (and often combined, for when till 
> rolls with custom printing is desired). So it may be that although 
> paper tape is no longer available from computer stationary suppliers, 
> it can very easily be made in quite small MOQs.

How does one, using modern equipment, both slit and perforate (feed
holes) blank tape?  Color me curious.

--Chuck


--
This email has been checked for viruses by Avast antivirus software.
www.avast.com

[cctalk] Re: IBM RT Graphics

[Paul Koning via cctalk]

> On Jun 8, 2023, at 12:06 PM, Jonathan Stone via cctalk 
>  wrote:
> 
> On Thursday, June 8, 2023 at 05:20:28 AM PDT, Santo Nucifora via cctalk 
>  wrote:
> 
>> I bought mine from this ebay auction:  https://www.ebay.com/itm/171649843131
>> Specifically, the "D-SUB 3W3 Male" item. 
> 
> [...]
> 
> Note these are 50 Ohm impedance. I always assumed the OEM originals were 75 
> Ohm.
> I've not been able to find 75 Ohm equivalents in the past 3 years I've been 
> looking.
> 
> OTOH I'm not a hardware person, I have no idea if a ~1.5cm-long connector 
> matters, especially if it's connected to a non-coaxial VGA cable, then to the 
> VGA input of a multi-sync flat panel display. (I'm not sufficiently retro to 
> want to go back to carrying 19in sync-on-green CRTs)

Normal VGA connectors are DE-15, which have no defined impedance in the first 
place.  No, short unmatched segments like that don't matter at all, not at VGA 
frequencies.

If a cable claims to be VGA but isn't coax I would call it fake.  An actual 
cable carrying video signals does need to be coax, and does need to be the 
correct impedance (i.e., 75 ohms). 

paul

[cctalk] Re: Source for NEW (unused) punch tape

[William Sudbrink via cctalk]

The punch (on an ASR33 anyway) punches the feed (center) holes.  All the rolls 
I have are completely unperforated.

-Original Message-
From: Chuck Guzis via cctalk [mailto:cctalk@classiccmp.org]
Sent: Thursday, June 08, 2023 12:10 PM
To: Adrian Godwin via cctalk 
Cc: Chuck Guzis 
Subject: [cctalk] Re: Source for NEW (unused) punch tape

On 6/8/23 08:52, Adrian Godwin via cctalk wrote:
> I think paper-slitters are pretty common. That is to say, if you go to
> anyone manufacturing adding machine rolls they will have the
> capability to make custom widths in rather small job lots. It's an
> industry comparable with printing (and often combined, for when till
> rolls with custom printing is desired). So it may be that although
> paper tape is no longer available from computer stationary suppliers,
> it can very easily be made in quite small MOQs.

How does one, using modern equipment, both slit and perforate (feed
holes) blank tape?  Color me curious.

--Chuck


--
This email has been checked for viruses by Avast antivirus software.
www.avast.com

[cctalk] Re: IBM RT Graphics

[Jon Elson via cctalk]

On 6/8/23 11:06, Jonathan Stone via cctalk wrote:

  On Thursday, June 8, 2023 at 05:20:28 AM PDT, Santo Nucifora via 
cctalk  wrote:


I bought mine from this ebay auction:https://www.ebay.com/itm/171649843131
Specifically, the "D-SUB 3W3 Male" item.

[...]

Note these are 50 Ohm impedance. I always assumed the OEM originals were 75 Ohm.
I've not been able to find 75 Ohm equivalents in the past 3 years I've been 
looking.

OTOH I'm not a hardware person, I have no idea if a ~1.5cm-long connector 
matters, especially if it's connected to a non-coaxial VGA cable, then to the 
VGA input of a multi-sync flat panel display. (I'm not sufficiently retro to 
want to go back to carrying 19in sync-on-green CRTs)


A 1.5" long pigtail of the wrong impedance would have very 
little effect if the pixel clock is under 100 MHz.  A 2 M 
long VGA cable with a bunch of wires in a shield DEFINITELY 
causes visible artifacts on a mid-frequency VGA.  A long 
time ago I actually had to make my own VGA cables with HD15 
connectors and RG-178 cable, because stock cables were total 
crap!


Jon

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

A slitter is a wide paper feed system with sharp-edged pulleys over which
it passes. There are quite a few videos of this on youtube, it's
surprisingly well documented. Because slitter manufacturers are selling to
mom-and-pop outfits.

I think the tape is supplied unpunched and the tape punch makes both feed
holes and data holes. I could be wrong.


On Thu, Jun 8, 2023 at 5:10 PM Chuck Guzis via cctalk 
wrote:

> On 6/8/23 08:52, Adrian Godwin via cctalk wrote:
> > I think paper-slitters are pretty common. That is to say, if you go to
> > anyone manufacturing adding machine rolls they will have the capability
> to
> > make custom widths in rather small job lots. It's an industry comparable
> > with printing (and often combined, for when till rolls with custom
> printing
> > is desired). So it may be that although paper tape is no longer available
> > from computer stationary suppliers, it can very easily be made in quite
> > small MOQs.
>
> How does one, using modern equipment, both slit and perforate (feed
> holes) blank tape?  Color me curious.
>
> --Chuck
>

[cctalk] Re: Source for NEW (unused) punch tape

[Chuck Guzis via cctalk]

On 6/8/23 08:52, Adrian Godwin via cctalk wrote:
> I think paper-slitters are pretty common. That is to say, if you go to
> anyone manufacturing adding machine rolls they will have the capability to
> make custom widths in rather small job lots. It's an industry comparable
> with printing (and often combined, for when till rolls with custom printing
> is desired). So it may be that although paper tape is no longer available
> from computer stationary suppliers, it can very easily be made in quite
> small MOQs.

How does one, using modern equipment, both slit and perforate (feed
holes) blank tape?  Color me curious.

--Chuck

[cctalk] Re: IBM RT Graphics

[Jonathan Stone via cctalk]

 On Thursday, June 8, 2023 at 05:20:28 AM PDT, Santo Nucifora via cctalk 
 wrote:

> I bought mine from this ebay auction:  https://www.ebay.com/itm/171649843131
>Specifically, the "D-SUB 3W3 Male" item. 

[...]

Note these are 50 Ohm impedance. I always assumed the OEM originals were 75 Ohm.
I've not been able to find 75 Ohm equivalents in the past 3 years I've been 
looking.

OTOH I'm not a hardware person, I have no idea if a ~1.5cm-long connector 
matters, especially if it's connected to a non-coaxial VGA cable, then to the 
VGA input of a multi-sync flat panel display. (I'm not sufficiently retro to 
want to go back to carrying 19in sync-on-green CRTs)
  

[cctalk] Re: Source for NEW (unused) punch tape

[Adrian Godwin via cctalk]

I think paper-slitters are pretty common. That is to say, if you go to
anyone manufacturing adding machine rolls they will have the capability to
make custom widths in rather small job lots. It's an industry comparable
with printing (and often combined, for when till rolls with custom printing
is desired). So it may be that although paper tape is no longer available
from computer stationary suppliers, it can very easily be made in quite
small MOQs.

I don't know this for sure and I haven't called anyone, it's just a
recollection from when my father ran a stationary business that till rolls
aren't always high-volume products from till manufacturers but low-volume
customised supplies  made very flexibly.


On Thu, Jun 8, 2023 at 4:43 PM David Gesswein via cctalk <
cctalk@classiccmp.org> wrote:

> Someone did a paper-slitter in this thread
>
>
> https://forum.vcfed.org/index.php?threads/paper-tape-punch-service-and-request.1242805/page-2#post-1319033
>
> On Mon, Jun 05, 2023 at 06:19:26PM -, robot...@gmail.com wrote:
> > For various reasons (including, but not limited to, insanity and
> obsessiveness*) I am building a diode laser based tape punch. It's not
> specifically for a classic comp, but I'd like to stick with standard format
> so that it'd be useful for making custom tapes for members in the future. I
> will probably need to make dozens of tapes so using actual, vintage rolls
> is out of the question. Does anyone know if 1" tape is used for anything
> else and where I might find some new? Otherwise I may have to add
> paper-slitter to my project list and make my own.
> >
> >
> >
> >
> > *I've had the idea of a lost-media ARG stuck in my head for years.
> >
> > --
>

[cctalk] Re: Source for NEW (unused) punch tape

[David Gesswein via cctalk]

Someone did a paper-slitter in this thread

https://forum.vcfed.org/index.php?threads/paper-tape-punch-service-and-request.1242805/page-2#post-1319033

On Mon, Jun 05, 2023 at 06:19:26PM -, robot...@gmail.com wrote:
> For various reasons (including, but not limited to, insanity and 
> obsessiveness*) I am building a diode laser based tape punch. It's not 
> specifically for a classic comp, but I'd like to stick with standard format 
> so that it'd be useful for making custom tapes for members in the future. I 
> will probably need to make dozens of tapes so using actual, vintage rolls is 
> out of the question. Does anyone know if 1" tape is used for anything else 
> and where I might find some new? Otherwise I may have to add paper-slitter to 
> my project list and make my own.
> 
> 
> 
> 
> *I've had the idea of a lost-media ARG stuck in my head for years.
> 
> --

[cctalk] Re: IBM RT Graphics

[Santo Nucifora via cctalk]

Looking back, I did buy one from Digikey but it was not the right one.

I bought mine from this ebay auction:  https://www.ebay.com/itm/171649843131
Specifically, the "D-SUB 3W3 Male" item.  I did not install the three metal
coax covers that come with it.  The end looks like this:
https://vintagecomputer.ca/wp-content/uploads/2023/06/IBM_RT_3W3_end.jpg

Hope this helps.
Santo




On Thu, Jun 8, 2023 at 7:34 AM emanuel stiebler  wrote:

> On 2023-06-08 06:12, Santo Nucifora via cctalk wrote:
>
> > I got the 3W3 connector and parts from Digikey.   Here's what that looks
> > like:
> >
> https://vintagecomputer.ca/wp-content/uploads/2023/06/IBM_RT_3W3_RGB-rotated.jpg
> > Please forgive the crude construction.  I didn't think it would work but
> it
> > did.
>
> You still have the part numbers?
>
>

[cctalk] Re: IBM RT Graphics

[emanuel stiebler via cctalk]

On 2023-06-08 06:12, Santo Nucifora via cctalk wrote:


I got the 3W3 connector and parts from Digikey.   Here's what that looks
like:
https://vintagecomputer.ca/wp-content/uploads/2023/06/IBM_RT_3W3_RGB-rotated.jpg
Please forgive the crude construction.  I didn't think it would work but it
did.


You still have the part numbers?

[cctalk] Re: IBM RT Graphics

[Santo Nucifora via cctalk]

On Wed, Jun 7, 2023 at 2:26 PM Jonathan Katz via cctalk <
cctalk@classiccmp.org> wrote:

> I have an IBM 6152 aka IBM RT system I rescued. (It may be a 6151?)
> I'm 90% sure it has colour graphics. The system does seem to POST
> correctly (according to the LED on the front) but the CRT is dead. I'm
> wondering if anyone has built an adapter to hook this to a VGA
> monitor.
>
>
Do you have the Megapel adapter in your 6151 with the 3W3 connector?  I
have one in my 6150 and I was able to connect it to a VGA monitor (NEC
Multisync) and I think I only created an adapter to go from 3W3 to Red,
Green and Blue RCA plugs (component) that then went into a simple RGB
component to VGA wired adapter (about 6 inches long) I already had.   Part
of the magic might be in that multisync monitor though.

Here it is running AIX:
https://vintagecomputer.ca/wp-content/uploads/2023/06/IBM_PC_RT_running_AIX.jpg

I got the 3W3 connector and parts from Digikey.   Here's what that looks
like:
https://vintagecomputer.ca/wp-content/uploads/2023/06/IBM_RT_3W3_RGB-rotated.jpg
Please forgive the crude construction.  I didn't think it would work but it
did.

Here is the RGB component to VGA adapter I also used:
https://vintagecomputer.ca/wp-content/uploads/2023/06/RGB2VGAadapter.jpg

Hope this helps.
Santo