38 replies to this topic

[Goochman]

So I was the lucky one to win the first ST Scandoubler box which allows you to connect your ST to an LCD monitor via the VGA port.

I finally got some time to play around with a little bit and have to say it works great!  The low res pics were under a setting which was not ideal - I noticed it more when I switched to medium res hence those shots are a bit clearer (ignoring the shakey camera hand blur )

Anyhow - here are a few pics.  The creator said he is working on an edition that supports all 3 rez's from 1 box.  I have a Mono->VGA cable so I dont need that, but still if you are looking for a solution to you ST monitor issue this is it!

If you want me to test something else with this let me know - the sound worked perfectly with my PC speaker set.

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[onlysublime]

wow.  looks great.  didn't even know Wolfenstein 3D was made for the ST (though it probably pales in comparison to the Atari Jaguar version which was far superior to the original PC version).

[OldSchoolRetroGamer]

Interesting...is this device available to others? Is there a link/price or pre-order available?

[Goochman]

Here is the webpage - he puts them up on eBay:
http://www.scandoubl...screenshots.php

[onlysublime]

woah!  90 pounds is over $140.  dream is crushed...  

[Goochman]

I won mine for 51 pounds on ebay

[poobah]

So, what's inside?
I'm still speculating its a generic scan doubler board with some signal conditioning.
The signal conditioning is the key

[Goochman]

I dont know whats inside - its a pretty fancy device if you ask me - there are 4 buttons that allow for picture correction/rez selection/language.

Whatever it is, its the first all in 1 solution Ive seen to get the ST on an LCD monitor.

[amiman99]

poobah, on Sun Apr 15, 2012 10:23 AM, said:

So, what's inside?
I'm still speculating its a generic scan doubler board with some signal conditioning.
The signal conditioning is the key

It's GBS-8220 , search on ebay for "Arcade VGA" many of them are shipped from China at around $30 with free shipping.

I have one of those boards and it works great with Amiga PCs.
ST requires a sync combiner, because the 15KHz input needs composite sync and ST provides H+V only.
If you have a ST with composite OUT then you could extract sync signal from it using an IC (I forgot the #).

[poobah]

amiman99, on Wed Apr 18, 2012 12:41 PM, said:

poobah, on Sun Apr 15, 2012 10:23 AM, said:

So, what's inside?
I'm still speculating its a generic scan doubler board with some signal conditioning.
The signal conditioning is the key

It's GBS-8220 , search on ebay for "Arcade VGA" many of them are shipped from China at around $30 with free shipping.

I have one of those boards and it works great with Amiga PCs.
ST requires a sync combiner, because the 15KHz input needs composite sync and ST provides H+V only.
If you have a ST with composite OUT then you could extract sync signal from it using an IC (I forgot the #).

Yah, I've got one here on my bench. The ST sync signals are a a bit squirrely tho.
Got some ideas.

[amiman99]

There are few ways to get the composite sync:
1. Using LM1881, only works with composite out models like STFM
2. Using logic gates (I will look for a link)
3. Combine both sync with resistors and http://www.atari-for...=17153&start=25 and http://eab.abime.net...ead.php?t=51326

go and experiment!

[unholy]

The first part of this article describes both methods of combining sync signals.

[amiman99]

Here is the gate circuit very similar to the one posted above.

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[DarkLord]

How big is this device - would it be possible to take the outer casing off, and
use it internally?

Thanks!

[poobah]

DarkLord, on Wed Apr 18, 2012 7:32 PM, said:

How big is this device - would it be possible to take the outer casing off, and
use it internally?

Thanks!

4.5" square or so, plus a little bit of perf board for the xor gates and a mux

[onlysublime]

can this project be done by a neophyte?  I've love to pick up one of these GBS-8220 boards and make it work with the ST if I can.  I only have a 1040STf though.

[DarkLord]

poobah, on Wed Apr 18, 2012 8:05 PM, said:

4.5" square or so, plus a little bit of perf board for the xor gates and a mux

Hmm, and not very thick either. It does require a separate P/S?

I can't tell from the pictures or the items site or ebay, does it come with a cable
to go between the unit and the ST?

Thanks.

EDIT: Nevermind, seen it powers off the 2nd joystick port.

[poobah]

DarkLord, on Wed Apr 18, 2012 10:27 PM, said:

EDIT: Nevermind, seen it powers off the 2nd joystick port.

Which probably is not a good idea. The board calls for 5v, 2 amps. I'm using an old cisco brick for mine.

[DarkLord]

Er, so I can't tell from the pictures or the items site or ebay, does it come with a cable
to go between the unit and the ST?

Thanks!

[Goochman]

DarkLord, on Thu Apr 19, 2012 5:58 AM, said:

Er, so I can't tell from the pictures or the items site or ebay, does it come with a cable
to go between the unit and the ST?

Thanks!

Yes it comes with everything you need to get going.  I used it with my Mega2 ST with no problems powering on 2nd joystick port.  The power cable is a bit short which I told the author who will make it longer with the new boxes (he only had a 1040ST)

If someone in the US can produce these for a lower cost that would be great - I got mine for basically $100 shipped to me.

[Goochman]

One more note - the one I got came in a metal encasing with external buttons that could manipulate the up/down/menu options you see on the board which was required for me to get the picture correct on my LCD.

[poobah]

Goochman, on Thu Apr 19, 2012 9:19 AM, said:

DarkLord, on Thu Apr 19, 2012 5:58 AM, said:

Er, so I can't tell from the pictures or the items site or ebay, does it come with a cable
to go between the unit and the ST?

Thanks!

Yes it comes with everything you need to get going.  I used it with my Mega2 ST with no problems powering on 2nd joystick port.  The power cable is a bit short which I told the author who will make it longer with the new boxes (he only had a 1040ST)

If someone in the US can produce these for a lower cost that would be great - I got mine for basically $100 shipped to me.

2 amps is way too much to pull off the joystick port, Heck a 1040ST PS is only rated for 3A total on the 5v rail.

[Goochman]

What kind of PSU should I get?  I know almost nothing about these.

[amiman99]

Goochman, on Thu Apr 19, 2012 7:27 PM, said:

What kind of PSU should I get?  I know almost nothing about these.

I'm using 5v 1200mA (1.2A) switching PS with positive center.

[Chris Union NJ]

Yeah this is the same devise there was a thread on amibay the first post has the ST video pin outs..

http://www.amibay.co...ead.php?t=20468