1040 STe and the Gonbes 8220

[pixelmischief]

I've decided to "upgrade" my scan-doubler from the Ambery to the Gonbes and I have some questions.

 

1. If my 1040 STe has an RF modulator, pin 2 of the video port will push a composite video signal. True of False?

 

2. If pin 2 is pushing composite video, I can strip sync from it using an LM1881. True or False?

 

3. If my 1040 STe does not have an RF modulator, pin 2 of the video port will push a composite sync (H+V) signal. True or False?

 

4. The aforementioned composite sync signal on pin 2 will be compatible with the composite sync input on the Gonbes. True or False?

 

5. My 1040 STe pushes H sync on pin 9 and V sync on pin 12 of the video port. True of False?

 

6. The aforementioned sync signals can be safely combined into composite sync using a nand gate. True or False?

 

7. The aforementioned composite sync created by the nand gate would be compatible with the composite sync input on the Gonbes. True or False?

 

8. My 1040 STe pushes 12V at 10ma on pin 8. True or False?

 

9. The aforementioned power on pin 8 can be safely used to power the LM1881 and/or the nand gate. True or False?

 

10. My 1040 STe pushes R, G, and B signals on pins 7, 6, and 10; respectively. True or False?

 

11. The aforementioned R, G, and B signals will be compatible with the R, G, and B signal inputs on the Gonbes. True or False.

 

12. Which is the highest quality solution: composite sync on pin 2, sync stripped from pin 2, sync combined from pins 9 and 12?

 

13. Which is the most reliable of the aforementioned solutions?

[GadgetUK]

See the video I did on this - I think there's a diagram at 17mins 59. It's the same for the STe as STFM. One thing I got wrong when I wired it up the first time, I wired unused gates on the 74HC00 to ground - only the inputs of the unused gates should have been fed ground, not the outputs as well. I noticed it getting warm, thought about it, realised what I had done and had to take it to bits again to disconnect the outputs of the unused gates. It works really well once you've messed with the settings to get a good picture.

 

You can also buy an enclosure from these people:- http://arcadeforge.net/Scaler-and-Strike-Devices/Scaler-PCB-Enclosure::14.html

 

I later modified my LCD to take 5v out of the back of the LCD panel to power the GBS-8220. That way I don't need a separate PSU. You would need to check if your monitor can provide the 5v safely first though if you decide to try that. In my case the 5v standby is pretty beefy and hardly any current drawn by the monitor on that line at all.

 

Edited February 24, 2016 by GadgetUK

[pixelmischief]

Thanks for the reply! I hope mine come out a good-looking as yours!

Edited February 25, 2016 by pixelmischief

[galax]

That 'ghosting' around things that move drives me mad, I hate using the GBS because of it. Some people claim it doesn't happen to them, but I think they just don't notice it. In some games that there is a bit of compression/tearing or something if a lot changes on screen, but you're right it is less noticeable in a game than on the desktop or with a command line (like when I run my BBC micro through the GBS).

[GadgetUK]

Yeah, I notice it only on the cursor on the desktop. Same when I use my Amigas with the GBS-8220. I've played a tonne of games on it though and always get a fantastic picture. I've also done the mod to swap out the cap on the 3.3v regulator to a 22uF tantalum - as suggested by Steady from the Amiga forums.

[+poobah]

That 'ghosting' around things that move drives me mad, I hate using the GBS because of it. Some people claim it doesn't happen to them, but I think they just don't notice it. In some games that there is a bit of compression/tearing or something if a lot changes on screen, but you're right it is less noticeable in a game than on the desktop or with a command line (like when I run my BBC micro through the GBS).

 

Yah, I've observed that on several revisions of the GBS. Not sure why it does it, but the 'halo' around the mouse makes me crazy.

[pixelmischief]

Yah, I've observed that on several revisions of the GBS. Not sure why it does it, but the 'halo' around the mouse makes me crazy.

 

I can understand how the Gonbes "glass" effect would be terribly distracting for a desktop user. I don't use any of my Atari computers for regular desktop work, but if I did, it would justify the presence on my desktop of a dedicated monitor. The NEC 1970VX is a solution without equal.

[calimero]

I had GBS 8200

 

I asked on atari-forum what can be done with this jerkying on GSM 8200 and Simbo gave me instructions: http://www.atari-forum.com/viewtopic.php?t=17153&start=125#p221079

[galax]

I haven't thrown mine away because as a backup it is better than nothing... but only just.

[pixelmischief]

I haven't thrown mine away because as a backup it is better than nothing... but only just.

 

Really? It's that bad? Even for full-screen game-play?

[galax]

Really? It's that bad? Even for full-screen game-play?

 

Compared to the other display options I have, yes. I have several scan converters that are better, LCD monitors that show ST low res, and 12" and 14" Atari CRTs. Gonbes is at the bottom of the pile with RF

[pixelmischief]

Gonbes is at the bottom of the pile with RF

 

You're trippin'.

[GadgetUK]

I had GBS 8200

 

I asked on atari-forum what can be done with this jerkying on GSM 8200 and Simbo gave me instructions: http://www.atari-forum.com/viewtopic.php?t=17153&start=125#p221079

LOL!!! It isn't that bad, well it can be - I think it depends on the revision of board you buy. Some suffer from snow like on black backgrounds etc, but I do get a really good display using one of these. Granted theres't the slight ghost on the cursor on the desktop but I play a lot of games on my ST and Amiga using this and it looks great (for the price). Sure if you can find the right Dell or NEC multisync you can probably get all 3 resolutions on that but I think you then get bottom chopped off etc. I think the Dell is the better of the two options from what I've seen and read.

[calimero]

GBS is really ok for games but it is horrible (my subject opinion) for Dekstop use.

 

"bottom chopped off" - I think that only Amiga suffer from this on e.g. Nec.

[galax]

Sure if you can find the right Dell or NEC multisync you can probably get all 3 resolutions on that but I think you then get bottom chopped off etc. I think the Dell is the better of the two options from what I've seen and read.

With the right monitor and cable you can definitely get all 3 resolutions. I only have the NEC Multisyncs, but from what I've seen they are pretty much the same as the Dells, with the Dells apparently requiring manual centering every boot, which would be a bit annoying. Both monitors suffer from missing vertical columns of pixels in medium resolution - but with access to both high and low rez who would use medium?