NeXT Computers Forum Index NeXT Computers
www.NeXTComputers.org
 
Log in to check your private messagesLog in to check your private messages

Log inLog in  RegisterRegister


Profile  Search  Memberlist  FAQ  Usergroups
Use other "greyscale" monitors with mono systems?
Goto page Previous  1, 2, 3  Next
 
Post new topic   Reply to topic    NeXT Computers Forum Index -> Black Hardware
View previous topic :: View next topic  
Author Message
Arti77



Joined: 15 Oct 2006
Posts: 8
Location: Melbourne, Australia

PostPosted: Mon Nov 20, 2006 6:28 pm    Post subject: Reply with quote

This is exciting! Please post some pics soon. Maybe I will be able to use my monostation Very Happy
Back to top
View user's profile Send private message
w2510a



Joined: 19 Nov 2006
Posts: 6

PostPosted: Tue Nov 21, 2006 7:30 am    Post subject: Connecting PC monitors to NextStation Mono Reply with quote

Hi all,

I made the adapter myself, just a quick-and-dirty hack, even without any printed circuits (just "on the fly"). There is an FAQ describing the DB 19 pinout and the trick to power up the Next, please search in Google for the keywords "kwellsch next monitor"). I just connected DB 19 PIN 10 (video) with the R, G, B input of my XGA monitor (3 BNC input connectors), PINS 8 and 9 with the appropriate sync inputs and implemented the power on switch as described in the FAQ (i.e. a push button between pins 6 and 19).
Everything works fine now, except the missing input devices ;-(
Back to top
View user's profile Send private message
w2510a



Joined: 19 Nov 2006
Posts: 6

PostPosted: Tue Nov 21, 2006 12:36 pm    Post subject: Re: Connecting PC monitors to NextStation Mono Reply with quote

w2510a wrote:
Hi all,

I made the adapter myself, just a quick-and-dirty hack, even without any printed circuits (just "on the fly"). There is an FAQ describing the DB 19 pinout and the trick to power up the Next, please search in Google for the keywords "kwellsch next monitor"). I just connected DB 19 PIN 10 (video) with the R, G, B input of my XGA monitor (3 BNC input connectors), PINS 8 and 9 with the appropriate sync inputs and implemented the power on switch as described in the FAQ (i.e. a push button between pins 6 and 19).
Everything works fine now, except the missing input devices ;-(


And here are the images:



As you can see - quick and dirty, but it works!
Back to top
View user's profile Send private message
nextchef



Joined: 17 Aug 2006
Posts: 1006
Location: Missouri, USA

PostPosted: Tue Nov 21, 2006 2:20 pm    Post subject: Reply with quote

Thanks for the pics, as they seem to make things a little clearer, at least for me. Can you snap a pic of the monitor in action, so we get an idea of what one can expect from this setup?

So the next thing to do would be to wire up the remaining wires to the proper pins on another DB-19 male connector so you could connect to a soundbox. Then the sound, keyboard and mouse connected to it should work. I guess you would then not need the switch, as the power button on the keyboard would perform that function.

Very interesting indeed. Gonna have to go by Gateway Electronics and get me some connectors.

Chef
_________________
Chef
Back to top
View user's profile Send private message
brams



Joined: 27 Dec 2005
Posts: 508
Location: Blackburn, England

PostPosted: Tue Nov 21, 2006 11:46 pm    Post subject: Reply with quote

nextchef wrote:
Thanks for the pics, as they seem to make things a little clearer, at least for me. Can you snap a pic of the monitor in action, so we get an idea of what one can expect from this setup?

So the next thing to do would be to wire up the remaining wires to the proper pins on another DB-19 male connector so you could connect to a soundbox. Then the sound, keyboard and mouse connected to it should work. I guess you would then not need the switch, as the power button on the keyboard would perform that function.

Very interesting indeed. Gonna have to go by Gateway Electronics and get me some connectors.

Chef


I'm surprised this works as well as it reportedly does, IDC/ribbon cables are not really suited to HF video signals.
_________________
NeXTcube Turbo Dimension, NeXTstation Turbo Color, MP2100, Q840av, Q650, WS G4 500, Pismo G4 550, SGI Octane R12K MXE, BeBox 133.
Back to top
View user's profile Send private message Send e-mail Visit poster's website AIM Address Yahoo Messenger MSN Messenger
nextchef



Joined: 17 Aug 2006
Posts: 1006
Location: Missouri, USA

PostPosted: Wed Nov 22, 2006 8:09 am    Post subject: Reply with quote

brams wrote:
I'm surprised this works as well as it reportedly does, IDC/ribbon cables are not really suited to HF video signals.


I am not an electrical engineer by any means, but is it possible that his cable choice has dampened the signal down enough to keep from getting the ghosting problem others have experienced? Hopefully a pic can be posted of the screen in action, so others who have tried this can compare and contrast with their results.

Chef
_________________
Chef
Back to top
View user's profile Send private message
brams



Joined: 27 Dec 2005
Posts: 508
Location: Blackburn, England

PostPosted: Wed Nov 22, 2006 8:19 am    Post subject: Reply with quote

nextchef wrote:
I am not an electrical engineer by any means, but is it possible that his cable choice has dampened the signal down enough to keep from getting the ghosting problem others have experienced? Hopefully a pic can be posted of the screen in action, so others who have tried this can compare and contrast with their results.

Chef


Me neither, and I guess anything is possible, that much I know having seen all sorts of strange things that break the rules. Some kinds of cables SCSI and Video spring to mind as well as some of the esoteric Hi-Fi interconnects have certain capacitance values for whatever reason. Video cables for monitors are supposed to be I think about 75Ω resistance. I suppose it's kind of obvious if you look at a decent cable you can see that are usually unbalanced, shielded co-axial cables.

I think my take on this would be, use a decent BNC cable, whack the end of and put a DB-19 or whatever it is that fits on the back of the NeXT and then make a Y cable out of whatever (an old PC floppy cable) to the Soundbox. Kind of like an homebrew codged together Y cable
_________________
NeXTcube Turbo Dimension, NeXTstation Turbo Color, MP2100, Q840av, Q650, WS G4 500, Pismo G4 550, SGI Octane R12K MXE, BeBox 133.
Back to top
View user's profile Send private message Send e-mail Visit poster's website AIM Address Yahoo Messenger MSN Messenger
nextchef



Joined: 17 Aug 2006
Posts: 1006
Location: Missouri, USA

PostPosted: Wed Nov 22, 2006 8:58 am    Post subject: Reply with quote

brams wrote:
nextchef wrote:
I am not an electrical engineer by any means, but is it possible that his cable choice has dampened the signal down enough to keep from getting the ghosting problem others have experienced? Hopefully a pic can be posted of the screen in action, so others who have tried this can compare and contrast with their results.

Chef


Me neither, and I guess anything is possible, that much I know having seen all sorts of strange things that break the rules. Some kinds of cables SCSI and Video spring to mind as well as some of the esoteric Hi-Fi interconnects have certain capacitance values for whatever reason. Video cables for monitors are supposed to be I think about 75Ω resistance. I suppose it's kind of obvious if you look at a decent cable you can see that are usually unbalanced, shielded co-axial cables.

I think my take on this would be, use a decent BNC cable, whack the end of and put a DB-19 or whatever it is that fits on the back of the NeXT and then make a Y cable out of whatever (an old PC floppy cable) to the Soundbox. Kind of like an homebrew codged together Y cable


He is one step away from this. Just connect the "extra" wires to the proper pins on a DB19 (or modified DB25) connector and attach to a soundbox. I plan on trying this out over the thanksgiving holiday, assuming I can scrounge up the proper connectors.

Chef
_________________
Chef
Back to top
View user's profile Send private message
Arti77



Joined: 15 Oct 2006
Posts: 8
Location: Melbourne, Australia

PostPosted: Wed Nov 22, 2006 5:14 pm    Post subject: Reply with quote

Any idea what else uses a 19pin connector or where they can be purchased online?
Back to top
View user's profile Send private message
nextchef



Joined: 17 Aug 2006
Posts: 1006
Location: Missouri, USA

PostPosted: Wed Nov 22, 2006 9:33 pm    Post subject: Reply with quote

Arti77 wrote:
Any idea what else uses a 19pin connector or where they can be purchased online?


The Faq referenced earlier had some examples of how to modify a db25 connector for use in place of the DB19. I have not tried it myself, so I do not know how well it will work. Here is the link.

http://mail-index.netbsd.org/port-next68k/1998/06/30/0000.html

Chef
_________________
Chef
Back to top
View user's profile Send private message
w2510a



Joined: 19 Nov 2006
Posts: 6

PostPosted: Wed Nov 22, 2006 11:55 pm    Post subject: More info on monitor connector hack Reply with quote

Hi all,

I hope to get a soundbox in the next 2 weeks, then I will proceed further with the project (get input devices, connect the Next to a TFT instead of the trinitron monitor, etc.). Results will be provided here ;-)

Of course the used material is not exactly high quality (as I already mentioned before) but it is sufficient for my quick test - I just wanted to know if it works at all. You may even notice that i did not buy a DB19 connector, I just used a DB25 connector where I removed the additional connections with a small saw and rasp. If I find time I may measure the overall signal attenuation of the adapter to check if your assumptions regarding resistance are correct.

I will try to provide screen photographs, although they are usually a bit tricky because of the screen refresh/flickering.

BR,
GŁnther
Back to top
View user's profile Send private message
brams



Joined: 27 Dec 2005
Posts: 508
Location: Blackburn, England

PostPosted: Thu Nov 23, 2006 12:13 am    Post subject: Re: More info on monitor connector hack Reply with quote

w2510a wrote:
Hi all,

I hope to get a soundbox in the next 2 weeks, then I will proceed further with the project (get input devices, connect the Next to a TFT instead of the trinitron monitor, etc.). Results will be provided here ;-)

Of course the used material is not exactly high quality (as I already mentioned before) but it is sufficient for my quick test - I just wanted to know if it works at all. You may even notice that i did not buy a DB19 connector, I just used a DB25 connector where I removed the additional connections with a small saw and rasp. If I find time I may measure the overall signal attenuation of the adapter to check if your assumptions regarding resistance are correct.

I will try to provide screen photographs, although they are usually a bit tricky because of the screen refresh/flickering.

BR,
GŁnther


Thanks w2510a

I was'nt criticising what you'd shown us, on the contrary I'm grateful for your help. It just struck me that you where not using video cable so I'd have figured the picture might have been poor, but as you say it's fine and as Chef observed the cables properites may well be that fact it works so well.

Again thanks

BTW Blackcube has already shown us where DB-19's can be sourced This Thread
_________________
NeXTcube Turbo Dimension, NeXTstation Turbo Color, MP2100, Q840av, Q650, WS G4 500, Pismo G4 550, SGI Octane R12K MXE, BeBox 133.
Back to top
View user's profile Send private message Send e-mail Visit poster's website AIM Address Yahoo Messenger MSN Messenger
w2510a



Joined: 19 Nov 2006
Posts: 6

PostPosted: Fri Dec 22, 2006 8:21 am    Post subject: Nextstation Mono + Soundbox + VGA Monitor Reply with quote

Hello everybody,

I was busy the last few weeks, so it took longer than expected, but finally it is done: I have connected a Soundbox from a Non-ADB Nextstation Color to my Nextstation Mono. The original keyboard plugs into the Soundbox as always, it works perfectly also with the Nextstation Mono.
To connect a VGA/SXGA monitor, I have built an adapter as already posted in the forum some time ago. Everything works fine on CRT monitors like the Olivetti DSM 50-175 and the HP A4033A (from my HP 9000 715/80). On my Dell TFT, the image is too bright (seems like black & white without any grayscale "colors").
You can find some screenshots on Flickr, just search for my account (w2510a) and the keyword "nextstation". I also try to post the links directly below:
http://www.flickr.com/photos/62567718@N00/330084399/
http://www.flickr.com/photos/62567718@N00/330084396/
http://www.flickr.com/photos/62567718@N00/330084394/
http://www.flickr.com/photos/62567718@N00/330084393/
http://www.flickr.com/photos/62567718@N00/330084392/

Have fun!
Back to top
View user's profile Send private message
nextchef



Joined: 17 Aug 2006
Posts: 1006
Location: Missouri, USA

PostPosted: Fri Dec 22, 2006 8:55 am    Post subject: Reply with quote

Great job on this w2510a, and thanks for updating us all on your progress. I was hoping that this would be possible to do with a custom "Y" cable of sorts. If you get a chance, can you document how you wired all the connectors, so others can try. I picked up a couple of db19 connectors from Gateway, but have not had a chance to try anything out yet.

Congrats again on getting it to work.

Chef
_________________
Chef
Back to top
View user's profile Send private message
w2510a



Joined: 19 Nov 2006
Posts: 6

PostPosted: Sat Dec 23, 2006 5:07 am    Post subject: Wiring of custom made connector Reply with quote

Hi Chef & all,

actually the wiring for my connector is quite simple.
I use the monitor cable of the NextStation Mono (DB19 connectors on both ends) to connect the Next with the Soundbox.
On the Next machine, I have made a "dongle" which passes through all wires (DB19 male/female connectors). The following wires need to be connected with the VGA cable (DB15 connectors):
VSync: Next pin 8, connect with VGA pin 14
HSync: Next pin 9, connect with VGA pin 13
Video: Next pin 10, connect with the RGB VGA pins 1,2,3
GND: Next pins 13-19, connect with VGA pins 6,7,8

That's all!

Cheers,
w2510a
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    NeXT Computers Forum Index -> Black Hardware All times are GMT - 7 Hours
Goto page Previous  1, 2, 3  Next
Page 2 of 3

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum



Powered by phpBB © 2017 phpBB Group