HP 9144A and three QIC tapes available for free

[P Gebhardt]

Hi list,

3 years ago, I picked up an HP 9144A QIC tape drive with HP-IB interface. It 
came with three 16-track QIC tape drives. I never found the time to connect it 
to my HP 9000-300 and realized that I will probably never make use of it, which 
is why I'd like to give it to some other collector's hands who is interested. I 
powered up the drive for 2 hours, no smoke, the fan was running as expected. 
Nothing else tested.

Picture of the actual three tapes which come with the drive: 

http://www.digitalheritage.de/OTHER/20141223_155006_tn.JPG
I forgot to take pictures of the drive, but will do it, as soon as I can access 
it next week again.
In the mean time, here is another one of the tape drive (not mine):

http://www.hpmuseum.net/display_item.php?hw=257



The drive weights 9kg (20 lbs).
First come, first serve. Drive and tapes are for free. You have to pay shipping 
costs or come to pick it up. Location is Bonn, Germany.

Kind regards,
Pierre

 
--- 
Pierre's collection of classic computers moved to: http://www.digitalheritage.de

Re: Logic Analyzer software for the HP-IB/RS-232 bus pre-processor HP 10342B

[Mike Loewen]

On Fri, 22 May 2015, Marc Verdiell wrote:


This has probably been asked before, but does anyone have the software
package that came with the HP-IB/RS232 HP10342 bus pre-processor for the
HP1650 series Logic Analyzer (actually I have a 1670G)? It should have a
config file and an inverse assembler file. I'm interested in the HP-IB
files. Can't find it anywhere.


   Is it on this disk?

http://www.keysight.com/main/software.jspx?ckey=sw574&lc=eng&cc=US&nid=-536902556.536879990&id=sw574


Mike Loewen mloe...@cpumagic.scol.pa.us
Old Technology  http://q7.neurotica.com/Oldtech/

RE: Seeking keyboard for Compaq Portable

[Christopher Parish]

I actually just finished re-padding mine last night.  I struggled to find the 
right materials with the correct electrical properties, but I eventually came 
up with a process that works.

The mylar I had (conductive on one side and the plastic base on the other) 
wasn't working.  The plastic side did nothing and the metal side shorted the 
pins.  Out of frustration, I conformally coated the keyboard PCB with a thin 
layer of silicone (available at your favorite internet retailer), and now both 
aluminum HVAC tape and the mylar sheet (metal side down) work correctly.  I 
stuck with mylar because the aluminum tape tends to develop sharp corners and 
can scratch through the conformal coating over time.

So here's the stackup:

Double sided tape (3M 9474LE 300LSE)
Coarse open cell foam cut to height
Super glue
2mil thick mylar, metal side facing the keyboard

I used a 7/16" hole punch to shape each material.  The resulting keys feel 
almost the same as the ones I didn't re-pad.  Given the deterioration of the 
existing foam, I suspect that it's closer to the original feel anyway.

Hope that helps,
Christopher

Re: 8-bit Computer TV Channel Use

[Mark J. Blair]

Assuming that I don't find an off-the-shelf converter that Just Works for our 
poorly-behaving vintage computer video outputs, what I have in mind is this: A 
converter that is specifically designed to emulate the response of an 80's TV 
or 80's composite monitor when driven by a vintage computer output, and 
translate that as well as practical to modern displays (particularly, 1080p via 
HDMI). I have some ideas about how to accomplish this, but I will need to do 
more work to see if I can create a solution that is not absurdly expensive.

On the input side, I envision having two RCA jacks and an F connector, 
accepting composite video, Y/C separated video (for C64, etc.), or TV RF input. 
It should be able to accept NTSC or PAL, so the US and UK folks can play. Is 
there a need for SECAM, or any other video standards? What about other 
electrical interface options? I'm only hands-on familiar with US machines. I 
understand that Atari computers were especially popular in Poland, so I'd like 
to support those... anybody here know what format/channel a Polish Atari 8-bit 
would output?

In the middle will be some FPGA to perform any necessary magic. I've been 
looking at a prohibitively expensive ($115) one that has enough dual-port RAM 
blocks to support a frame buffer. I need to see if I can push the frame buffer 
out into external RAM in order to move to a cheaper FPGA. It would be ideal if 
the video parameters could be figure out automagically, but I have a feeling 
there will be a need for user-adjusted parameters, and possibly even loading up 
different FPGA programming to handle some odd-ball signal.

Output would be HDMI, at 1080p. Are other interfaces and/or resolutions 
desirable? I'd like to keep it as feature-simple as practical.

Handling the VHF/UHF tuner economically may be another sticky point. Maxim 
makes a tuner chip that's available at Digi-Key, but I refuse to design Maxim 
parts into anything on account of off-topic reasons. Mouser has stock of a very 
inexpensive ST tuner chip that looks very promising, but the full datasheet 
isn't openly available. I need to contact ST to see if I can talk them out of 
it. Their site mentions an NDA for the eval board, so it might be tough, 
particularly since my intention would be for my design to be open to allow 
off-label uses.

Assuming I don't lose interest before completing this (a high-risk caveat, 
naturally) and that I can find a way to make the price bearable, what do y'all 
think about this silliness? I'm particularly interested in learning about 
non-US TV formats so I can design in maximum utility.

-- 
Mark J. Blair, NF6X 
http://www.nf6x.net/

Re: 8-bit Computer TV Channel Use

[Chris Osborn]

On May 23, 2015, at 8:24 AM, Mark J. Blair  wrote:

> In the middle will be some FPGA to perform any necessary magic. I've been 
> looking at a prohibitively expensive ($115) one that has enough dual-port RAM 
> blocks to support a frame buffer.

Are you on the CoCo mailing list? Have you seen the RGB2VGA by Luis Antoniosi 
(CoCoDemus)? I know at one point he had been tinkering with making it support 
composite from the Apple II. It’s semi open-source, I think there are 2 
versions and the latest version is currently all closed source.

https://sites.google.com/site/tandycocoloco/rgb2vga

--
Follow me on twitter: @FozzTexx
Check out my blog: http://insentricity.com

Re: 8-bit Computer TV Channel Use

[Fred Cisin]

On Sat, 23 May 2015, Mark J. Blair wrote:
Assuming that I don't find an off-the-shelf converter that Just Works 
for our poorly-behaving vintage computer video outputs, what I have in 
mind is this: A converter that is specifically designed to emulate the 
response of an 80's TV or 80's composite monitor when driven by a 
vintage computer output, and translate that as well as practical to 
modern displays (particularly, 1080p via HDMI). I have some ideas about 
how to accomplish this, but I will need to do more work to see if I can 
create a solution that is not absurdly expensive.


Where are you located?
Would you like some of the REAL monitors?  They will do all sorts of 
bizarre artifacts that would be hard to emulate.  They are also perfect 
matches to the size weight, power draw, smell, reliability (or lack 
thereof), resolution (or lack thereof), etc.
Nothing truly duplicates the experience without drifting tuning, picky 
horizontal hold, a lttle flickering, etc.
I've long ago gotten rid of most of them, but there are always more 
breeding in the cracks of the woodwork.

Re: HP 9144A and three QIC tapes available for free

[SPC]

I have some HP9000 300 and I'd like to try it. I'm interested.

Regards
Sergio Pedraja

El Sabado, 23 de mayo de 2015, P Gebhardt  escribió:

> Hi list,
>
> 3 years ago, I picked up an HP 9144A QIC tape drive with HP-IB interface.
> It came with three 16-track QIC tape drives. I never found the time to
> connect it to my HP 9000-300 and realized that I will probably never make
> use of it, which is why I'd like to give it to some other collector's hands
> who is interested. I powered up the drive for 2 hours, no smoke, the fan
> was running as expected. Nothing else tested.
>
> Picture of the actual three tapes which come with the drive:
>
> http://www.digitalheritage.de/OTHER/20141223_155006_tn.JPG
> I forgot to take pictures of the drive, but will do it, as soon as I can
> access it next week again.
> In the mean time, here is another one of the tape drive (not mine):
>
> http://www.hpmuseum.net/display_item.php?hw=257
>
>
>
> The drive weights 9kg (20 lbs).
> First come, first serve. Drive and tapes are for free. You have to pay
> shipping costs or come to pick it up. Location is Bonn, Germany.
>
> Kind regards,
> Pierre
>
>
>
> ---
> Pierre's collection of classic computers moved to:
> http://www.digitalheritage.de
>


-- 
Gracias | Regards - Saludos | Greetings | Freundliche Grüße | Salutations
​
-- 
*Sergio Pedraja*
-- 
mobile: +34-699-996568
twitter: @sergio_pedraja | skype: Sergio Pedraja
--
http://plus.google.com/u/0/101292256663392735405
http://www.linkedin.com/in/sergiopedraja
http://www.quora.com/Sergio-Pedraja
http://spedraja.wordpress.com
https://www.xing.com/profile/Sergio_Pedraja 
-
No crea todo lo que ve, ni crea que está viéndolo todo

Re: 8-bit Computer TV Channel Use

[wulfman]

maybe this will do ?

http://www.ebay.com/itm/GBS-8220-RGB-CGA-EGA-YUV-to-VGA-ARCADE-VIDEO-CONVERTER-BOARD-Latest-Software-/120967105011?ssPageName=ADME:B:FSEL:US:1123



On 5/23/2015 8:24 AM, Mark J. Blair wrote:
> Assuming that I don't find an off-the-shelf converter that Just Works for our 
> poorly-behaving vintage computer video outputs, what I have in mind is this: 
> A converter that is specifically designed to emulate the response of an 80's 
> TV or 80's composite monitor when driven by a vintage computer output, and 
> translate that as well as practical to modern displays (particularly, 1080p 
> via HDMI). I have some ideas about how to accomplish this, but I will need to 
> do more work to see if I can create a solution that is not absurdly expensive.
>
> On the input side, I envision having two RCA jacks and an F connector, 
> accepting composite video, Y/C separated video (for C64, etc.), or TV RF 
> input. It should be able to accept NTSC or PAL, so the US and UK folks can 
> play. Is there a need for SECAM, or any other video standards? What about 
> other electrical interface options? I'm only hands-on familiar with US 
> machines. I understand that Atari computers were especially popular in 
> Poland, so I'd like to support those... anybody here know what format/channel 
> a Polish Atari 8-bit would output?
>
> In the middle will be some FPGA to perform any necessary magic. I've been 
> looking at a prohibitively expensive ($115) one that has enough dual-port RAM 
> blocks to support a frame buffer. I need to see if I can push the frame 
> buffer out into external RAM in order to move to a cheaper FPGA. It would be 
> ideal if the video parameters could be figure out automagically, but I have a 
> feeling there will be a need for user-adjusted parameters, and possibly even 
> loading up different FPGA programming to handle some odd-ball signal.
>
> Output would be HDMI, at 1080p. Are other interfaces and/or resolutions 
> desirable? I'd like to keep it as feature-simple as practical.
>
> Handling the VHF/UHF tuner economically may be another sticky point. Maxim 
> makes a tuner chip that's available at Digi-Key, but I refuse to design Maxim 
> parts into anything on account of off-topic reasons. Mouser has stock of a 
> very inexpensive ST tuner chip that looks very promising, but the full 
> datasheet isn't openly available. I need to contact ST to see if I can talk 
> them out of it. Their site mentions an NDA for the eval board, so it might be 
> tough, particularly since my intention would be for my design to be open to 
> allow off-label uses.
>
> Assuming I don't lose interest before completing this (a high-risk caveat, 
> naturally) and that I can find a way to make the price bearable, what do 
> y'all think about this silliness? I'm particularly interested in learning 
> about non-US TV formats so I can design in maximum utility.
>


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Sanyo Denki 1402-B2 (paper tape drive)

[Adrian Stoness]

anyone know how to hook these up?
has controllers to talk to a  Shibaura VMC-45 with a Tosnuc 600 control
picked it up for 50 bucks in near mint condition localy this week
and i'd like to hook it up to my laptop to back up every tape i got at this
time

Re: Sanyo Denki 1402-B2 (paper tape drive)

[Adrian Stoness]

o ye heres a pic
https://farm9.staticflickr.com/8780/17696207169_c892bffcbe_b.jpg

Re: 8-bit Computer TV Channel Use

[Jochen Kunz]

Am 23.05.15 um 17:24 schrieb Mark J. Blair:
> In the middle will be some FPGA to perform any necessary magic.
What about the analogy of Software Defined Radio:
Use only as much electronics as minimal necessary to get the input
signal digitized by a high speed ADC. Maybe some cheap DVB-T USB thing
can be abused for the ADC part. Do the processing in software on a
"normal" computer. (PeeCee, some ARM single board thing.)

Advantage:
- Converts to whatever video output your PeeCee has.
- Works on a laptop. No extra display needed when on the road.
- Easy to capture the video to generate AVI, MPEG, ...
- Scaling can be done by GPU of host computer. No need to reinvent the
  wheel. (If the existing GPU wheel fits the wagon...)
- Scaling and other processing can be done in easy to change software.
  That way it is easy to extent for other people. (Different scaling
  and interpolating algorithms. Adaption to the odd signal from some
  obscure hardware of other people.)
- Most likely cheaper then a stand alone solution.
- No obscure FPGA magic needed.

Disadvantage:
- needs extra PeeCee / ARM-SBC for processing.
- No obscure FPGA magic needed.
-- 

tschüß,
   Jochen

Re: 8-bit Computer TV Channel Use

[emanuel stiebler]

On 2015-05-23 09:59, Jochen Kunz wrote:


Advantage:
- No obscure FPGA magic needed.

Disadvantage:
- No obscure FPGA magic needed.


?
;-)

RE: 8-bit Computer TV Channel Use

[tony duell]

> Handling the VHF/UHF tuner economically may be another sticky point. Maxim 
> makes a tuner chip that's available 
> at Digi-Key, but I refuse to design Maxim parts into anything on account of 
> off-topic reasons. Mouser has stock of 
> a very inexpensive ST tuner chip that looks very promising, but the full 
> datasheet isn't openly available. I need to 
> contact ST to see if I can talk them out of it. Their site mentions an NDA 
> for the eval board, so it might be tough, 
> particularly since my intention would be for my design to be open to allow 
> off-label uses.

What I say below covers how it was generally done in the UK/Europe. No idea 
about elsewhere.

Building a UHF tuner (even assuming you have a working design) is non-trivial. 
To give you some idea, the 
inductors are often straight metal strips, layout and length is critical. If 
you bend one, you throw the tuning
way off

In the days of analogue TV, a lot of manufacturers had a tuner module. This was 
not regarded as field-
repairable. Some companies (e.g.  Philips) published data sheets on said 
tuners, and of course you could
buy the tuner as a spare part for the TV. It was typically a flat metal box 
with an aerial socket on the side. It took
a 12V supply and a tuning voltage (normally 0-33V, applied to varicap diodes in 
the tuner). It outputed an IF
signal (the receiver was a superhet, of course) around 35-40MHz. To control the 
tuning you either used a 
votlage stabiliser and a potentiometer (or several that could be pre-set for 
various channels and switched
between) or a frequency synthesiser type of circuit, the local oscillator from 
the tuner (divided down in
a lot of cases) was brought out for this. I remember a chip called the SAB3035 
CITAC (Computer Interface
for Tuning And Control) that was used here. 

The output of the tuner fed a suitable IF filter (a SAW device was about the 
easiest to use) then the IF
amplifiers (video and audio) and then detectors. There were ICs available for 
this. If you chose wisely the
only adjustment was the quadrature coil in the FM audio detector (in Europe, 
video was AM, audio FM on
analogue TV). Making the IF strip and detector was certianly possible, you had 
to do it on a ground-plane
PCB, and take some care with the layout, but it wasn't that bad. At least one 
UK company sold a kit for
this, I built a couple of them and they worked first time. Again, Philips were 
one of the companies who
made ICs for this, and data sheets were easy to come by.

Oh yes, in the UK the sound carrier was 6MHz offset from the video carrier, in 
the rest of Europe the spacing
was 5.5MHz. So if you want to handle sound (some computers sent their sound 
output over the RF output) you
may need to cover both.

At the output of this section you had composite video and line-level audio. 
What you do with those is up to
you

[As an off-topic aside : Philips (again) sold a range of solderless educational 
electronic kits, rather better
than the 150-in-1 ones normally encountered. I only had the basic kit and a 
couple of the add-ons when
I was a kid, they let me make radios (including superhets), Wien bridge 
oscillators, etc. But I wish I could
have afforded the EE1007 and EE1008 (manuals are on-line in German). They 
culimated in making a monochrome TV, yes, the tuner and IF strip were 
ready-built modules, as was the CRT PSU, but you still got to do a lot 
yourself and, learnt a lot in the process. Perhaps looking at said manuals will 
let you know what you 
up against.]

-tony

Re: 8-bit Computer TV Channel Use

[Mark J. Blair]

> On May 23, 2015, at 08:35, Chris Osborn  wrote:
> 
> 
> On May 23, 2015, at 8:24 AM, Mark J. Blair  wrote:
> 
>> In the middle will be some FPGA to perform any necessary magic. I've been 
>> looking at a prohibitively expensive ($115) one that has enough dual-port 
>> RAM blocks to support a frame buffer.
> 
> Are you on the CoCo mailing list? Have you seen the RGB2VGA by Luis Antoniosi 
> (CoCoDemus)? I know at one point he had been tinkering with making it support 
> composite from the Apple II. It’s semi open-source, I think there are 2 
> versions and the latest version is currently all closed source.
> 
> https://sites.google.com/site/tandycocoloco/rgb2vga


I'm on the list, but it's so high-volume that I rarely read it. I'll look at 
the RGB2VGA board to see if I might learn anything from it. His mention of a 
line buffer is already my "Oh, duh!" moment about how to use cheaper external 
SDRAM instead of on-FPGA dual-port memories for the frame buffer. The dual-port 
memories are very convenient, but having enough to form a frame buffer pushes 
the design up into over-$100 FPGAs.


> On May 23, 2015, at 08:36, Fred Cisin  wrote:
> Where are you located?
> Would you like some of the REAL monitors?

I'm in Riverside, CA, but I already have enough real monitors. :)


> On May 23, 2015, at 08:45, wulfman  wrote:
> 
> maybe this will do ?
> 
> http://www.ebay.com/itm/GBS-8220-RGB-CGA-EGA-YUV-to-VGA-ARCADE-VIDEO-CONVERTER-BOARD-Latest-Software-/120967105011?ssPageName=ADME:B:FSEL:US:1123
> 

It's similar, but probably not right for this application. It outputs VGA, 
which is already obsolescent, at a maximum resolution of 1360x768. The goal of 
this project is to drive modern 16:9 monitors and TVs at 1080p, over HDMI. I 
believe that board on eBay is intended for replacing monitors in coin-op video 
games, which generally have very different video hardware compared to vintage 
8-bit home computers. Has anybody tried this board with home computers that are 
known to be troublesome with modern displays? I'm at least interested in seeing 
how they got the price down to $40, and whether anything in their solution 
might be usable for this application without being able to read Chinese 
datasheets. :)


On May 23, 2015, at 08:59, Jochen Kunz  wrote:

> Am 23.05.15 um 17:24 schrieb Mark J. Blair:
>> In the middle will be some FPGA to perform any necessary magic.
> What about the analogy of Software Defined Radio:
> Use only as much electronics as minimal necessary to get the input
> signal digitized by a high speed ADC.

I initially considered using SDR techniques for the TV demodulation. Using an 
off-the-shelf TV tuner IC would probably be much cheaper than building an 
appropriate RF front end from scratch, though if it outputs an IF instead of 
baseband then SDR techniques might still be the cheapest way to extract the 
video baseband, since the design would have a couple of ADCs in it in any case 
to handle Y/C from a C64. Don't want the ADCs to be too expensive, though...

> Maybe some cheap DVB-T USB thing
> can be abused for the ADC part. Do the processing in software on a
> "normal" computer. (PeeCee, some ARM single board thing.)
> Disadvantage:
> - needs extra PeeCee / ARM-SBC for processing.
> - No obscure FPGA magic needed.

+ Latency

I think that's a non-starter due to latency. I can't imagine the overall 
latency being lower than several video frames, and that would be a killer for 
games. If it could work with sufficiently low latency, then using something 
like a Raspberry Pi or Beaglebone Black instead of a PC could lower the price 
and make it more stand-aloney.



-- 
Mark J. Blair, NF6X 
http://www.nf6x.net/

Re: 8-bit Computer TV Channel Use

[Mark J. Blair]

> On May 23, 2015, at 09:25, tony duell  wrote:
> 
>> Handling the VHF/UHF tuner economically may be another sticky point. Maxim 
>> makes a tuner chip that's available 
>> at Digi-Key, but I refuse to design Maxim parts into anything on account of 
>> off-topic reasons. Mouser has stock of 
>> a very inexpensive ST tuner chip that looks very promising, but the full 
>> datasheet isn't openly available. I need to 
>> contact ST to see if I can talk them out of it. Their site mentions an NDA 
>> for the eval board, so it might be tough, 
>> particularly since my intention would be for my design to be open to allow 
>> off-label uses.
> 
> What I say below covers how it was generally done in the UK/Europe. No idea 
> about elsewhere.
> 
> Building a UHF tuner (even assuming you have a working design) is 
> non-trivial. To give you some idea, the 
> inductors are often straight metal strips, layout and length is critical. If 
> you bend one, you throw the tuning
> way off

Yup. I'm a radio amateur and an electrical engineer working with GPS stuff, so 
I understand the pain! But nowadays, a VHF/UHF tuner is a single IC, possibly 
surrounded by a small handful of fixed inductors. The problems are:

* Might not be able to buy it in small quantity.
* Might need to read Chinese to understand the datasheet.
* Datasheet might simply be unavailable to individuals, even if the part is 
available.

I haven't begun trying to crack that egg yet, but there may a successful path 
there. With modern parts, even a dumb digital designer like me can successfully 
design RF front ends operating at 1.5 GHz, and cram an entire GPS receiver onto 
a fingernail-sized PCB. It's black magic if somebody makes the right chip. And 
it's still do-able if they don't make the magic chip... it's just a lot more 
expensive than consumer electronics have conditioned us to expect.

I think there used to be a rule of thumb for microwave work to not try for over 
10dB of gain per inch of circuit, or something like that. But now, slapping 
down a 20dB or greater gain LNA circuit the size of a barley corn is no big 
deal. Being able to make the whole circuit a lot smaller than a wavelength 
eliminates a lot of the pain.

As an example, Mouser carries a single-chip tuner for $2.32 at quantity 1. It's 
by Silicon Labs (I think I mistakenly states ST earlier). But only a short-form 
datasheet is available openly, and I need to contact SiLabs to see if I can get 
a full datasheet. I also don't know whether this analog TV tuner chip will 
remain in production, vs. Mouser buying some TV manufacturer's leftover parts.

> The output of the tuner fed a suitable IF filter (a SAW device was about the 
> easiest to use) then the IF
> amplifiers (video and audio) and then detectors.

The output of a single-chip tuner might also be at IF. The Maxim part (which I 
will not use) outputs at 36 MHz, I think. Can't tell the output of the SiLabs 
part without more info. Hopefully it's either baseband or a lower IF frequency 
that I could sample with a cheaper ADCs for digital down-conversion. Needing to 
support a 36 MHz IF would probably increase ADC cost vs. using ones that just 
need to sample baseband or a low IF.

SAW filters are also black magic, and nowadays they are TINY!

> Oh yes, in the UK the sound carrier was 6MHz offset from the video carrier, 
> in the rest of Europe the spacing
> was 5.5MHz. So if you want to handle sound (some computers sent their sound 
> output over the RF output) you
> may need to cover both.

And US NTSC puts the sound carrier at 4.5 MHz, so there's another thing in 
favor of using SDR techniques for some portion of the demodulation if I can't 
find a Magic Chip that does the work more cheaply. The chroma subcarriers are 
also at different frequencies in the various standards.


> 
> At the output of this section you had composite video and line-level audio. 
> What you do with those is up to
> you

And that's where the fun begins! The plan is to infer what color the vintage 
computer was trying to display at any given pixel, with knowledge of the dirty 
tricks it used to get that color cheaply. Then cram that inferred pixel into 
the frame buffer, and convert the video format on the other side of the frame 
buffer.

-- 
Mark J. Blair, NF6X 
http://www.nf6x.net/

Re: 54 TK50 tapes on eBay

[Mark J. Blair]

I got my TK50 drive from eBay. Boy, that tape feeding mechanism sure looks 
screwy! I'd like to get a modern DLT drive for my modern computer backups 
(after I sell a few more kidneys, that is), but I'm still a bit suspicious of 
their similar (identical?) tape feeding scheme. All of my bad experience with 
things like QIC, DAT, etc. had led me to be very suspicious of tape systems 
other than 1/2" open reel.

-- 
Mark J. Blair, NF6X 
http://www.nf6x.net/

RE: 8-bit Computer TV Channel Use

[Christopher Parish]

> ...
> His mention of a line buffer is already my "Oh, duh!" moment 
> about how to use cheaper external SDRAM instead of on-FPGA 
> dual-port memories for the frame buffer. The dual-port memories 
> are very convenient, but having enough to form a frame buffer 
> pushes the design up into over-$100 FPGAs.
> 
> Mark J. Blair, NF6X 
> http://www.nf6x.net/

Don't forget that most FPGA block RAMs can be accessed in a dual ported manner 
even if they aren't physically laid out that way.  Depending on the color space 
and resolution, most FPGAs should be able to satisfy the RAM requirements for a 
framebuffer.  I know the Xilinx ones provide the required IP for free, and I'm 
sure other manufacturers do as well.  Depending on how much RAM you need, 
external memory could be the most cost effective approach anyway.

Christopher

Re: 54 TK50 tapes on eBay

[Johnny Billquist]

On 2015-05-23 19:04, Mark J. Blair wrote:

I got my TK50 drive from eBay. Boy, that tape feeding mechanism sure looks screwy! 
I'd like to get a modern DLT drive for my modern computer backups (after I sell a 
few more kidneys, that is), but I'm still a bit suspicious of their similar 
(identical?) tape feeding scheme. All of my bad experience with things like QIC, 
DAT, etc. had led me to be very suspicious of tape systems other than 1/2" open 
reel.


It's not that bad. The TK50 sometimes get the pickup unhooked from the 
arm, but once you realize how it works, it's really easy to fix it when 
that happens. Apart from that, the tape movement works fine. When the 
pickup lead gets unhooked you cannot even put a cartridge in.


The other problem (as I mentioned) is dirty heads. That will cause the 
tape to fail to actually load, since the heads will move up and down 
trying to find track 1 and eventually give up. At which point you see it 
flashing quickly red on the load button.


The third issue is a general problem with just one button expected to do 
all functions, and just one lamp in the button indicating issues. The 
drive can just get confused, and you cannot tell what it is doing, and 
it is not possible to unload the tape. Very annoying. You can usually 
solve that by power cycling the thing.


This all worked better in the TK70. I guess they had to figure things 
out by trial and error. :-)


Johnny

--
Johnny Billquist  || "I'm on a bus
  ||  on a psychedelic trip
email: b...@softjar.se ||  Reading murder books
pdp is alive! ||  tryin' to stay hip" - B. Idol

Re: 8-bit Computer TV Channel Use

[Steven Hirsch]

On Sat, 23 May 2015, Chris Osborn wrote:



On May 23, 2015, at 8:24 AM, Mark J. Blair  wrote:

In the middle will be some FPGA to perform any necessary magic. I've 
been looking at a prohibitively expensive ($115) one that has enough 
dual-port RAM blocks to support a frame buffer.


Getting an acceptable combination of crisp 80-column text and proper color 
aliasing from a converter is decidedly non-trivial.  I own one of just 
about every commercially available (and hobby) converters and precisely 
none of them provides a universal solution.  Some give great displays from 
an Amiga and suck for anything else.  Of my two (pricey) CVP CM-345S 
converters, only one provides useable display from an Apple IIGS.  My 
GBBS-8220 can occasionally be coaxed into giving a solid display from a 
Color Computer 3.  The list goes on...


Are you on the CoCo mailing list? Have you seen the RGB2VGA by Luis 
Antoniosi (CoCoDemus)? I know at one point he had been tinkering with 
making it support composite from the Apple II. It’s semi open-source, I 
think there are 2 versions and the latest version is currently all 
closed source.


Luis's converter comes the closest to providing usable display from an 
Apple II, but (for me at least) only with certain levels FPGA code. 
Still, he is putting a huge amount of effort into the project and I have 
high hopes this may be a robust one-size-fits-all solution.


If transparent, tweak-free emulation of a classic CRT display were easily 
doable, it would have been done by now.



--

RE: 8-bit Computer TV Channel Use

[tony duell]

> The output of a single-chip tuner might also be at IF. The Maxim part (which 
> I will not use) outputs at 36 MHz, I 
> think. Can't tell the output of the SiLabs part without more info. Hopefully 
> it's either baseband or a lower IF 

36MHz does sound like the standard TV IF frequency.

> frequency that I could sample with a cheaper ADCs for digital 
> down-conversion. Needing to support a 36 MHz 
> IF would probably increase ADC cost vs. using ones that just need to sample 
> baseband or a low IF.

> SAW filters are also black magic, and nowadays they are TINY!

Problem with TINY parts is soldering them :-). The SAW filters I used (with a 
conventional tuner module) were
round metal cans about 0.5" in diameter with 8 pins on IIRC a 0.1" spacing. 
Very easy to handle. If you are 
designing something for others to build (even in principle, i.e. you are making 
it an open design) then using 
impossible to handle parts is a bad thing if there are alternatives.

> > Oh yes, in the UK the sound carrier was 6MHz offset from the video carrier, 
> > in the rest of Europe the spacing
> > was 5.5MHz. So if you want to handle sound (some computers sent their sound 
> > output over the RF output) you
> > may need to cover both.


> And US NTSC puts the sound carrier at 4.5 MHz, so there's another thing in 
> favor of using SDR techniques for 
> some portion of the demodulation if I can't find a Magic Chip that does the 
> work more cheaply. The chroma 
> subcarriers are also at different frequencies in the various standards.

And IIRC US NTSC uses AM sound (Europe uses FM). I think you can forget about 
stereo sound, since
I doubt any home computer had a stereo RF modulator.

Be warned that there are many versions of PAL. PAL B/G and PAL I are the ones 
used in Europe and the UK, and
are basically compatible apart from the sound carrier offset (there are other 
differences, but they are unlikely
to matter here). But there is also PAL M and PAL N. at least. I forget which 
way round they are, but both have
a colour carrier around 3.58MHz. One is 625 line the other is 525 line. I think 
one was used for TV in South
America, did any home computers there use it? 

I doubt you would have to support system A (405 line) or system E (819 line), 
both AFAIK were only ever used
for monochrome signals. I can't think of a computer that would use them.

>
> > At the output of this section you had composite video and line-level audio. 
> > What you do with those is up to
> > you

> And that's where the fun begins! The plan is to infer what color the vintage 
> computer was trying to display at 
> any given pixel, with knowledge of the dirty tricks it used to get that color 
> cheaply. Then cram that inferred pixel 
> into the frame buffer, and convert the video format on the other side of the 
> frame buffer.

Sure. I think that is the interesting (and complex) part of the project. If you 
can get that right, you could even
just tell users to either tap the video off at the input to the RF modulator, 
or use an old VCR for the tuner/IF
section. 

Evil thought (and I have not worked this out yet). You are going to be 
connecting the RF signal straight from
the computer to this unit. Do you really need a _tuner_? You have essentially 
one strongish signal. What about
an untuned receiver and demodulator? At VHF totally possible, UHF might be a 
lot harder...

-tony




--
Mark J. Blair, NF6X 
http://www.nf6x.net/

Re: 8-bit Computer TV Channel Use

[Jochen Kunz]

Am 23.05.15 um 18:11 schrieb emanuel stiebler:
>> Advantage:
>> - No obscure FPGA magic needed.
>>
>> Disadvantage:
>> - No obscure FPGA magic needed.
> 
> ?
Depending on your personal preference FPGAs can be an annoying fight  in
an obscure HDL with proprietary tools running on Window$, or it can be
lots of fun and new things to learn. :-)
-- 

tschüß,
   Jochen

RE: 8-bit Computer TV Channel Use

[tony duell]

> Getting an acceptable combination of crisp 80-column text and proper color
> aliasing from a converter is decidedly non-trivial.  I own one of just
> about every commercially available (and hobby) converters and precisely
> none of them provides a universal solution.  Some give great displays from
> an Amiga and suck for anything else.  Of my two (pricey) CVP CM-345S
> converters, only one provides useable display from an Apple IIGS.  My
> GBBS-8220 can occasionally be coaxed into giving a solid display from a
> Color Computer 3.  The list goes on...

Given that the OP is planning on using an FPGA in his converter (not 
surpisingly), 
is the solution to have different configuration files for different machines? 
So the 
setup for an Apple ][ is optimised for its aliased colour, while that for a BBC 
micro
handles 80 column text a bit better

-tony

Re: 8-bit Computer TV Channel Use

[Mark J. Blair]

> On May 23, 2015, at 10:28, Steven Hirsch  wrote:
> 
> On Sat, 23 May 2015, Chris Osborn wrote:
> 
>> 
>> On May 23, 2015, at 8:24 AM, Mark J. Blair  wrote:
>> 
>>> In the middle will be some FPGA to perform any necessary magic. I've been 
>>> looking at a prohibitively expensive ($115) one that has enough dual-port 
>>> RAM blocks to support a frame buffer.
> 
> Getting an acceptable combination of crisp 80-column text and proper color 
> aliasing from a converter is decidedly non-trivial.

Even back in the day, I believe it involved swapping the cable between a 
monochrome monitor and a color one. I expect that this universal converter idea 
will require a way for the user to tell it whether they want color or 
monochrome video at the moment (and might as well let them choose what color 
phosphor to emulate). That way, an Apple II user who wishes to use modern 
displays could switch between 80 column mono mode for text or color mode for 
graphics, without swapping cables or displays.


>  I own one of just about every commercially available (and hobby) converters 
> and precisely none of them provides a universal solution.  Some give great 
> displays from an Amiga and suck for anything else.  Of my two (pricey) CVP 
> CM-345S converters, only one provides useable display from an Apple IIGS.  My 
> GBBS-8220 can occasionally be coaxed into giving a solid display from a Color 
> Computer 3.  The list goes on...

Aha! I've heard Nth-hand accounts of trouble getting vintage computers to play 
with video converters, but you sound like one of the folks with firsthand 
experience.

> If transparent, tweak-free emulation of a classic CRT display were easily 
> doable, it would have been done by now.

Agreed! I envision that the converter should have some sort of smarts to help 
it figure out what sort of input it sees, but even in the ideal case it'll 
probably need some capability for user tweaking or mode switching for corner 
cases.

> On May 23, 2015, at 10:41, tony duell  wrote:
> 
> Problem with TINY parts is soldering them :-). The SAW filters I used (with a 
> conventional tuner module) were
> round metal cans about 0.5" in diameter with 8 pins on IIRC a 0.1" spacing. 
> Very easy to handle. If you are 
> designing something for others to build (even in principle, i.e. you are 
> making it an open design) then using 
> impossible to handle parts is a bad thing if there are alternatives.

The SAW filters I used are small enough that my 46-year-old eyes have trouble 
seeing them without a magnifying glass. :) I do almost all of my soldering 
under a stereo microscope any more. But I can solder down to 0201 discretes 
that way, although I don't like going smaller than 0402. I don't have a lot of 
experience with hot air soldering yet, but it has become quite available to 
hobbyists, with hot air systems now available for around $100. The "Maker" 
movement has done a lot of good in the area of making surface mount soldering 
more approachable by Joe Random Hobbyist.

Now, one of the engineering problems I'd need to solve would be how FEW PCB 
layers I could get away with using that FPGA. 16+ layers is not uncommon for 
full die escape, but layer counts like that are far too expensive at the 
volumes this thing might sell in. Cell phones have high layer counts, but only 
because they sell in huge volumes.

I favor Xilinx FPGAs since they're what I use in my day job, and those are all 
BGAs. I would not offer this device as a kit in any case; I've helped Ian out 
doing rework for US FreHD customers, and even good old through-hole soldering 
can be hard for folks without a lot of experience. I'd rather design for 
automated assembly than spend a lot of time on tech support for kit builders 
who had trouble. With a BGA on it, the board's going through a reflow oven 
anyway.

> And IIRC US NTSC uses AM sound (Europe uses FM). I think you can forget about 
> stereo sound, since
> I doubt any home computer had a stereo RF modulator.

No, I think it's FM. I recall listening to TV audio on my US FM tactical mil 
radios whose frequency coverage extended over the bottom 2-3 VHF TV channels, 
back before they turned off the analog broadcasts. I agree that stereo support 
isn't needed, as stereo TV post-dates the computers in question if I'm not 
mistaken. But if I do the final demod digitally in an FPGA, then adding AM 
support wouldn't be a big deal if needed.

> Be warned that there are many versions of PAL.

That sounds like a deep rabbit hole to fall down! It might result in a case of 
"if you want me to add support for the computers from your country, send me one 
so I can develop with it". But this is also a point in favor of using an FPGA: 
Fairly major architectural changes just look like firmware upgrades to the end 
user, who can remain blissfully ignorant of my development pain. :) If I use 
one of the Zynq chips (which I'm currently favoring), then upgrades can 
probably be as simple as swapping an SD car

Re: 8-bit Computer TV Channel Use

[Chris Osborn]

On May 23, 2015, at 9:33 AM, Mark J. Blair  wrote:

> Has anybody tried this board with home computers that are known to be 
> troublesome with modern displays? 

The GBS-8200/8220 doesn’t support composite input, only RGB. I’ve used the 
board on quite a few of my computers that output RGB and it works fine. I’ve 
even got a couple of blog posts:

ZX Spectrum 128:http://www.insentricity.com/a.cl/233
Commodore 128 CGA:  http://www.insentricity.com/a.cl/219 
BBC Micro:  http://www.insentricity.com/a.cl/211

I still need to hook it up to the CoCo 3 RGB, but I can’t imagine any reason it 
wouldn’t work. It also works fine with my Apple IIgs.

--
Follow me on twitter: @FozzTexx
Check out my blog: http://insentricity.com

Re: 8-bit Computer TV Channel Use

[Steven Hirsch]

On Sat, 23 May 2015, Chris Osborn wrote:

The GBS-8200/8220 doesn’t support composite input, only RGB. I’ve used 
the board on quite a few of my computers that output RGB and it works 
fine. I’ve even got a couple of blog posts:


ZX Spectrum 128:http://www.insentricity.com/a.cl/233
Commodore 128 CGA:  http://www.insentricity.com/a.cl/219
BBC Micro:  http://www.insentricity.com/a.cl/211

I still need to hook it up to the CoCo 3 RGB, but I can’t imagine any 
reason it wouldn’t work. It also works fine with my Apple IIgs.


That really surprises me.  Mine was utterly unusable with the IIGS.  The 
desktop (and all icons, folders, etc.) had distinct vertical bands through 
them.  Also, lots of dot-crawl at sharp edges from what I recall.


I rather strongly suspect that there isn't any such thing as a single 
GBBS-8200.  Rather, the manufacturer is constantly changing the firmware 
(if not hardware) and it's a crap shoot as to what particular 
ideosyncrasies will be encountered with an individual board.


Has anyone heard talk of the GBBS boards being field flashable?



--

Re: 8-bit Computer TV Channel Use

[Steven Hirsch]

On Sat, 23 May 2015, Mark J. Blair wrote:




On May 23, 2015, at 10:28, Steven Hirsch  wrote:

On Sat, 23 May 2015, Chris Osborn wrote:



 I own one of just about every commercially available (and hobby) 
converters and precisely none of them provides a universal solution. 
Some give great displays from an Amiga and suck for anything else.  Of 
my two (pricey) CVP CM-345S converters, only one provides useable 
display from an Apple IIGS.  My GBBS-8220 can occasionally be coaxed 
into giving a solid display from a Color Computer 3.  The list goes 
on...


Aha! I've heard Nth-hand accounts of trouble getting vintage computers 
to play with video converters, but you sound like one of the folks with 
firsthand experience.


Yes, with all the scars and credit-card activity to prove it.



--

Re: 8-bit Computer TV Channel Use

[Chris Osborn]

On May 23, 2015, at 12:05 PM, Steven Hirsch  wrote:

> That really surprises me.  Mine was utterly unusable with the IIGS.  The 
> desktop (and all icons, folders, etc.) had distinct vertical bands through 
> them.  Also, lots of dot-crawl at sharp edges from what I recall.

I believe mine is a knock-off clone, and not a “genuine” GBS-8200.

--
Follow me on twitter: @FozzTexx
Check out my blog: http://insentricity.com

Re: 8-bit Computer TV Channel Use

[Chris Elmquist]

On Saturday (05/23/2015 at 11:30AM -0700), Chris Osborn wrote:
> 
> On May 23, 2015, at 9:33 AM, Mark J. Blair  wrote:
> 
> > Has anybody tried this board with home computers that are known to be 
> > troublesome with modern displays? 
> 
> The GBS-8200/8220 doesn’t support composite input, only RGB. I’ve used the 
> board on quite a few of my computers that output RGB and it works fine. I’ve 
> even got a couple of blog posts:
> 
> ZX Spectrum 128:  http://www.insentricity.com/a.cl/233
> Commodore 128 CGA:http://www.insentricity.com/a.cl/219 
> BBC Micro:http://www.insentricity.com/a.cl/211
> 
> I still need to hook it up to the CoCo 3 RGB, but I can’t imagine any reason 
> it wouldn’t work. It also works fine with my Apple IIgs.

The GBS-8200/8220 does support CGA and I have successfully used it
with various DEC terminals (VT240, Rainbow) by front-ending it with
a modern sync seperator (TI LMH1980) so that, in the case of VT240,
which does sync-on-green, I ended up with RGB and H and V sync going
into the GBS-8200.   Looks great on a 15" VGA LCD...

Chris
-- 
Chris Elmquist NØJCF

Re: 54 TK50 tapes on eBay

[Steven M Jones]

On 05/23/2015 10:04, Mark J. Blair wrote:

I'd like to get a modern DLT drive for my modern computer backups


The current hotness is LTO (Linear Tape Open), I think LTO-5 gives you 
3.0TB assuming 2:1 compression - and LTO-6 is probably the current flavor.



(after I sell a few more kidneys, that is)


Careful hunting on eBay can produce LTO-4 capabilities (0.8/1.6TB) for 
not too many vital organs. Just make sure you've got a fibre channel or 
SAS interface to talk to it.



... but I'm still a bit suspicious of their similar (identical?) tape feeding 
scheme. All of my bad experience with things like QIC, DAT, etc. had led me to be 
very suspicious of tape systems other than 1/2" open reel.


If you take a careful look at the TK and DLT mechanisms, I think you'll 
see that they're an awful lot closer to an open reel design than any of 
the cartridge designs (QIC, DAT, 8mm, AIT, etc).


I'd never say they're perfect because that would immediately render all 
my backups on any media unreadable. But if I have to trust a tape 
mechanism, I'll stick with the TK-DLT-LTO line.


--S.

Re: 8-bit Computer TV Channel Use

[Chris Osborn]

On May 23, 2015, at 12:35 PM, Chris Elmquist  wrote:

> The GBS-8200/8220 does support CGA 

The GBS-8200/8220 supports analog signals, not digital. It will directly 
support the 15khz misnamed “CGA” of arcade monitors (which is the same RGB 
signal the IIgs puts out), but that’s an analog signal, not digital. For use 
with the Commodore 128 I had to build a small circuit which converts the RGBI 
signal to analog RGB.

In the case of the BBC Micro which also puts out 5V TTL digital RGB, I didn’t 
bother with lowering the levels since the GBS-8200 didn’t care and I didn’t 
need to deal with a 4th intensity signal.

--
Follow me on twitter: @FozzTexx
Check out my blog: http://insentricity.com

Re: 54 TK50 tapes on eBay

[Mark J. Blair]

> On May 23, 2015, at 12:40, Steven M Jones  wrote:
> 
>> (after I sell a few more kidneys, that is)
> 
> Careful hunting on eBay can produce LTO-4 capabilities (0.8/1.6TB) for not 
> too many vital organs. Just make sure you've got a fibre channel or SAS 
> interface to talk to it.

Right. Me being the smart, forward-thinking guy I'm not, I bought a nice, sexy 
Mac Pro, and then a nice little mid-range QNAP NAS that has neither fibre 
channel nor SAS capabilities before I determined that I really could use proper 
tape backup and started investigating what interfaces are suitable for that. 
There's one very nice-looking LTO-6 drive with a Thunderbolt interface that 
will plug into my Mac Pro. Lots of kidneys for that one!

> 
>> ... but I'm still a bit suspicious of their similar (identical?) tape 
>> feeding scheme. All of my bad experience with things like QIC, DAT, etc. had 
>> led me to be very suspicious of tape systems other than 1/2" open reel.
> 
> If you take a careful look at the TK and DLT mechanisms, I think you'll see 
> that they're an awful lot closer to an open reel design than any of the 
> cartridge designs (QIC, DAT, 8mm, AIT, etc).
> 
> I'd never say they're perfect because that would immediately render all my 
> backups on any media unreadable. But if I have to trust a tape mechanism, 
> I'll stick with the TK-DLT-LTO line.

Thank you for the reassurances about the mechanism family. That will help once 
I stumble over another cache of unguarded kidneys. :)


-- 
Mark J. Blair, NF6X 
http://www.nf6x.net/

Re: 8-bit Computer TV Channel Use

[Mark J. Blair]

Speaking of digital RGB (and RGBI) interfaces, the hardware cost of adding them 
to an FPGA-based converter would be so cheap that I might as well add them to 
the plan. Will an analog RGB interface for converting things like 15kHz Amiga 
outputs feature-creep its way in there, too, I wonder? :)

-- 
Mark J. Blair, NF6X 
http://www.nf6x.net/

Re: 8-bit Computer TV Channel Use

[Chuck Guzis]

There are probably a fair number of "TV cards" in both ISA and PCI 
wandering about, since they're not terribly useful with the advent of 
digital TV (and the web).


Has anyone hooked up an ordinary NTSC modulator with one of those and an 
8 bit PC that relies on the peculiarities of NTSC chroma encoding?


If so, how's the reception quality?

--Chuck

Monitor wanted (was Re: 8-bit Computer TV Channel Use)

[Eric Smith]

On Sat, May 23, 2015 at 9:36 AM, Fred Cisin  wrote:
> Would you like some of the REAL monitors?  They will do all sorts of bizarre

I'd like some of the REAL monitors, such as an NEC Multisync 3, that
can do VGA *and* NTSC-rate analog RGB.  At some point the monitor
companies stopped bothering to make them handle horizontal scan rates
below 30 kHz.

RE: Memory options for an HP 1000 (HP 21MX / 2112A)

[Marc Verdiell]

Yes I was asking myself the same question, and your answers continue to help
a lot. 

I think I should retrace the path of technology evolution. Start getting it
up with paper tape tests and BCS. That probably means working mostly in
assembly and getting to know the most basic level of the machine. Which is
just about what the doctor prescribed. 

Then add the mag tape for which I have the tape and the cards.

I got a 7900 disk though (with cables and power supply, but no interface
cards to go with it!). I'd love to get that one going later on. Then it
would make sense to have the bigger memory to run disk based OS systems. So
7900 interface card and memory are definitely on my hunt list...

By the way I also have a punched card reader which I just restored.
Documation ML600, but the exact same model that HP re-branded I believe. Do
you know which interface cards I need to connect it to the HP-1000? I
suppose one of the 16 bit IO ones with a driver to go with it?

Sorry to keep picking your brain, but that is so much more efficient than
trying to piece it together (usually wrong at first) from an disorganized
pile of documentation!

Marc


From: "J. David Bryan" 
>> So I might be in the hunt for the cards or alternate solutions you
>> mentioned.

>I'd suggest that the question to answer first is whether you want to expend

>the effort and expense to gather the moderate amount of additional hardware

>necessary to run one of the more advanced disc-based OS versions that can 
>use DMS.  Note that the design of the memory mapping hardware in the 1000 
>requires explicit software support (i.e., programming of the DMS hardware) 
>in order to use more than 32KW of memory.  Earlier OSes that did not 
>support DMS will simply ignore all memory in the machine over 32K, even 
>when DMS is present.
>With the hardware you have, you can run a paper-tape based OS, such as BCS 
>(the Basic Control System) in 24K.  BCS is fairly primitive, but it does 
>offer an assembler, FORTRAN IV, and ALGOL compilers, and paper-tape BASIC 
>interpreters were also available (from the user contributed library).
>The hardware requirements for running the disc-based RTEs are listed on 
>these HP Computer Museum pages:
>  http://www.hpmuseum.net/display_item.php?sw=565
>  http://www.hpmuseum.net/display_item.php?sw=566
> -- Dave

Re: Monitor wanted (was Re: 8-bit Computer TV Channel Use)

[Chuck Guzis]

On 05/23/2015 04:24 PM, Eric Smith wrote:

On Sat, May 23, 2015 at 9:36 AM, Fred Cisin  wrote:

Would you like some of the REAL monitors?  They will do all sorts of bizarre


I'd like some of the REAL monitors, such as an NEC Multisync 3, that
can do VGA *and* NTSC-rate analog RGB.  At some point the monitor
companies stopped bothering to make them handle horizontal scan rates
below 30 kHz.


Find an old Mitsubishi Diamondscan, say the AUM-1381A and you can pretty 
much do anything up to 800x600 VGA.


You want connectors?  It's got connectors.

http://www.wonkity.com/~wblock/a4000hard/m1381.html

--Chuck

Re: Logic Analyzer software for the HP 10342B pre-processor

[Marc Verdiell]

>From: Mike Loewen 
> Is it on this disk?
>
http://www.keysight.com/main/software.jspx?ckey=sw574&lc=eng&cc=US&nid=-5369
02556.536879990&id=sw574

No, but a generous member of this list sent me the files off line. Is this a
helpful group or what. I am all set.
Marc

Re: PDP-12 Restoration at the RICM

[Michael Thompson]

We spent Friday and Saturday debugging the PDP-12. We replaced a bad SN7400
driver chip and three bad bulbs in the front panel. We can now trust what
we see on the front panel for debugging information.

We tried some of the PDP-8 and LINC instructions and noticed that some of
the bits in the Instruction Register were stuck on. We swapped the two M216
(six flip-flops in three SN7474 ICs) flip-chips that make up the IR and the
stuck bits moved. We replaced the broken M216 with a spare, and now all of
the IR bits work correctly. With a working IR, we found that lots of the
PDP-8 instructions, and many of the LINC instructions now work. We can turn
the relays on and off and make noises through the speaker.

During other DEC restorations we have replaced LOTs of SN7474 ICs. We
pulled all of the M216 flip-chips and ran them in Warren's tester. We found
and replaced another bad M216, the one in slot E8 that controls the core
memory states. Now core memory works!

We went through the troubleshooting guide in Maintenance Volume-II. It has
a procedure for doing a quick test of core memory that revealed a problem
in the upper addresses. From looking at the prints it had to be one of two
G221 flip-chips. We swapped in a spare and found that the one in slot C09
was bad. Now all of the first 4k of memory works.

There is a problem with any PDP-8 instruction that has an address in the
lower 9 bits. All 12 bits of the instruction are used, so it makes a mess.
Debugging that issue will be the next project.

-- 
Michael Thompson

Re: 8-bit Computer TV Channel Use

[Chuck Guzis]

If you want to go big-screen, some of the Presentation displays (e.g. 
Mitsubishi Megaview Pro) have very wide sync ranges (e.g. Horizontal 
15-90Khz) that should do very well.  They're all CRTs and range up into 
the 55 inch range, so you should have a strong back...


--Chuck

More HP-1000 Parts - Get 'em while they last!

[HP Friedrichs]

I recently posted reference to a page on my personal web site listing HP-1000 
assets for sale. There was a flurry of interest. As of this afternoon, the last 
of a half-dozen boxes were shipped to the new owners of many of these items. 
Thank you to everyone for their interest and thank you for your patience. 

Several individuals have expressed interest in acquiring more parts. The good 
news is that I still have items left. 

The bad news is that the 256k and 128K memory boards, +True In/Out, Term, 
Timebase, Error Correct, FPP Arith, and FPP control cards are all gone. So 
consider this fair warning: If there is something else you need to restore your 
system or to build a reserve of spares, now is the time to grab it before it's 
gone, too.

The inventory sheets have been updated on my site to reflect what is left. Some 
items are being offered piece-by-piece, some I'd prefer to sell as a set. 
Details are on my site. 

www.hpfriedrichs.com/hpfparts/hpfparts.htm

73,
Pete
AC7ZL

Re: Monitor wanted (was Re: 8-bit Computer TV Channel Use)

[Eric Smith]

On 05/23/2015 04:24 PM, Eric Smith wrote:
> I'd like some of the REAL monitors, such as an NEC Multisync 3, that
> can do VGA *and* NTSC-rate analog RGB.  At some point the monitor
> companies stopped bothering to make them handle horizontal scan rates
> below 30 kHz.

On Sat, May 23, 2015 at 6:56 PM, Chuck Guzis  wrote:
> Find an old Mitsubishi Diamondscan, say the AUM-1381A and you can pretty
> much do anything up to 800x600 VGA.

I was given a few Mitsubishi Diamondscan CRT monitors last year, but
unfortunately they're too new to support 15kHz horizontal.

Re: Monitor wanted (was Re: 8-bit Computer TV Channel Use)

[Ed Sharpe]

a lot of monitors  have been and are being  junked 
Back when we were getting a lot in  we would set xtras in the alley
I hope someone got them that will treasure them.
Ed# 
 
 
-Original Message-
From: Eric Smith 
To: General Discussion: On-Topic and Off-Topic Posts 
Sent: Sat, May 23, 2015 9:15 pm
Subject: Re: Monitor wanted (was Re: 8-bit Computer TV Channel Use)


On 05/23/2015 04:24 PM, Eric Smith wrote:
> I'd like some of the REAL monitors,
such as an NEC Multisync 3, that
> can do VGA *and* NTSC-rate analog RGB.  At
some point the monitor
> companies stopped bothering to make them handle
horizontal scan rates
> below 30 kHz.

On Sat, May 23, 2015 at 6:56 PM, Chuck
Guzis  wrote:
> Find an old Mitsubishi Diamondscan, say the
AUM-1381A and you can pretty
> much do anything up to 800x600 VGA.

I was
given a few Mitsubishi Diamondscan CRT monitors last year, but
unfortunately
they're too new to support 15kHz horizontal.

 

RE: Memory options for an HP 1000 (HP 21MX / 2112A)

[J. David Bryan]

On Saturday, May 23, 2015 at 17:48, Marc Verdiell wrote:

> I think I should retrace the path of technology evolution. Start
> getting it up with paper tape tests and BCS. That probably means working
> mostly in assembly and getting to know the most basic level of the
> machine. Which is just about what the doctor prescribed. 

Assuming that you have a working paper tape punch and reader, and the 
associated interface cards, then that's a very workable approach.


> I got a 7900 disk though (with cables and power supply, but no
> interface cards to go with it!). 

The interface is HP product number 13210A.  It's a two-card set; the card 
numbers are 13210-60004 and 13210-6.  The I/O cable is 13210-60003.


> I'd love to get that one going later on. Then it would make sense to
> have the bigger memory to run disk based OS systems. 

The 7900A was supported through the final RTE versions.  However, you could 
run the disc-based DOS-III OS with just the hardware and memory you have 
(assuming that you add the 7900 disc I/O interface).  With the addition of 
a HP 12539 Time-Base Generator card and 8K more of memory, you could also 
run RTE-II on a 7900.  Neither DMS nor more extensive memory is required 
for these OS versions, which are substantial steps up from BCS in terms of 
sophistication and ease of use.


> By the way I also have a punched card reader which I just restored.
> Documation ML600, but the exact same model that HP re-branded I
> believe. 

That's either the HP 2892A or 2893A, depending on whether it has a TTL or 
differential interface, respectively.


> Do you know which interface cards I need to connect it to the HP-1000? 

The interface is the HP 12924A, which was specific to the 2892A card 
reader.  The 2893A was supported only on the HP 3000, as far as I know.


> I suppose one of the 16 bit IO ones with a driver to go with it?

The general-purpose TTL interfaces apparently would not work.  Drivers for 
the card reader were supplied with the various OSes.


> Sorry to keep picking your brain, but that is so much more efficient
> than trying to piece it together (usually wrong at first) from an
> disorganized pile of documentation!

I'm glad that I can be of help.

  -- Dave