GBS-8200
So my RGB to VGA converter arrived. I’ll write up on how to connect a VGA monitor to the Amiga.
Requiremens:
- 23 Pin D-SUB Female (preferable with a casing)
- Solder iron + solder
- 5V / 2A DC adapter. These can be aquired from ebay.
- Some wire if you want the item to be further from the Amiga.
- And the “RGB to VGA converter” (search sentence in quotes used for ebay)
Difficulty: Easy
- Simple solder skills are required
Click on the images below for larger pictures
BGS 8200 with RGB wire
The item as aquired. It came with 2 sets of wires. One set for power (upper right corner of the pcb) and a set for video. A 5 1/4″ floppy has been placed behind it for reference of size. 
I’ve marked the 5 locations on the PCB that have interest for us.
- VGA output (connect the VGA monitor to this)
- 5V / 2A power input. The cable that comes with the converter can be plugged into the white socket.
- Menu buttons, change output resolution, adjust vertical/horizontal position etc. Change input source / auto detect input.
- B, G, R signal strength. Mine is set to max for all 3.
- RGB input from the amiga, using the cable shown on top of the picture.
The cable that came with my converter was properly colour coded, the RGB was proper red, green and blue, and gnd is black.
For this setup the V-Sync (yellow cable) is not needed.
23 pin connected to cable
On the picture above you can see how the cable needs to be connected to the solder side of the 23 Pin D-Sub female connector. Connect the finished wire to (5) and the amiga. Power on everything and you’re good to go.
Converted 640×256 to 1024×768
Finished picture.
This converter has a menu which came in Chinese. This can be changed in the menu, step one up, and select English.
The rest of the menu speaks for itself. The settings I adjusted was Horizontal/Vertical stretch, and Positioning. Also changed from 640×480 to 1024×768 for the output resolution.
I must confess that the image output is really great compared to the price.
32 Responses to Cheap RGB to VGA converter – Amiga
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Or just click the nice kiwi below ;-)
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It seems to produce very clear picture on the LCD !
Do you think it’s the same as this one http://www.vslcd.com/Specification/GBS8200.pdf (found also on ebay) !?
Yes, it looks to be the same one. There’s a GBS8220 version too, it’s almost the same but it has 2 VGA outputs.
Would also this work?
http://dx.com/p/composite-s-video-to-vga-converter-box-1280-1024px-max-110v-220v-ac-28534
That would work out of the box too if you are using the composite signal, but this isn’t available on all Amiga’s. i.e. the A500 does not have composite. Though if you have the TV tuner A590 or the adapter from AmigaManiac it can be used from there. The composite isn’t the best signal so some of the quality will already be lost there.
It would work from a Stock A1200 / A600 with no modifications
I have this. It does not work with SCART -> SCART AV-ADAPTER -> VGA CONVERTER because, as said, there is no AV-output from the Amiga.
1. If you’re answering to the original VGA adapter in the article the following applies.
thats a long way of converting a video signal. Keep it Simple and remove all unnessesary units.. you only need the 23pin connector to the VGA converter.
But:
it could be that it does not work because the Scart AV Adapter outputs Composite, then you’ll of course only need the composite signal and ground (composite is the yellow wire in the diagram that is not connected)
Of course in this manner you’ll need to select Composite INPUT on the VGA adapter.
Using composite signal is not recommended when you can get the best image using RGB.
it could also be that your scart cable has the resistors installed to work with modern TV’s, I cannot say of the impact it has on the VGA adapter other than making the signal worse.
2. if you’re replying to the device in the answer
you should check your Composite output of the scart to AV adapter, it could very well be that it doesn’t accept the input signals that the amiga delivers.
Thanks for sharing this article. I did contemplate some time ago whether to invest in this board but was concerned about the image reproduction quality, though from your snapshot it seems ok.
Cheers.
Hi, just few little questions.
what to do with the yellow cable leave it as it is or cut it? Sorry for my newbie question.
the second cable (black and red) isn’t necessary ? where can i connect it ?
You don’t need the yellow cable. Just wrap it up so it doesn’t annoy. For cables like this with a special connector, I always leave the cable on, not cutting it off. I never know if I’m going to use it for something else where I need the cable.
The Red/Black is the power cable.. it’s an alternative means of supplying the 5V required. If you look at the image of the board where I’ve squared out the sections. Section 2 (power) shows the well known connector and a small white one. The small white one is the one for the alternative power.
It’s up to you if you want to throw out the cable, or keep it. As stated earlier, I prefer to keep mine :-)
Hi, tanx for your answer Tomse. I saw a video on Youtube (http://www.youtube.com/watch?v=ka7H5MHw0FU) about the GBS-8200, and on the video the man connect the yellow cable also… why the yellow cable is not necessary ? And if I connect the yellow it’s a problem for my Amiga ?
The yellow cable is the composite signal.
You can connect it if you want to but the converter uses either RGB or Composite. So if the composite is chosen you’ll get a worse signal than the RGB.
It’ll be like you are connecting the composite cable to the TV.
You can add it or leave it. But if you add it and you’re not aware that the input selection is set to composite you’ll suffer from that.
It’s more of a pros and cons here.
you get 2 different input signals and can select these.
or if you select composite (and the yellow wire isn’t connected), you’ll get a screen with no input.
I prefer to leave it out, and have done so in this article due to the confusion which might occur.
Btw. are you the Quasar who scanned/made to PDF a lot of manuals ??
Hello tanx for all explanations. No I’m not the same Quasar.
You’re welcome. I hope you found the article useful :-)
This is the most inexpensive solution for the Amiga. I used it for my Amiga 500 that I purchased on Ebay. I dissected the monitor cable to get the RGB SYNC & GND to feed it into this board. Thank you for your post, there are people trying to charge $50+ for an A520 modulator that has garbage RF and composite video out.
I’m glad it is useful for you.
TV modulators are worth nothing except for the connector. So it doesn’t matter if it’s working or not. The analog RF signal is being outfased on modern TV’s.
I will be a bit daring now, I will try to use the same device with my Commodore 128 RGBi output. I think the principal you used for the Amiga should work for the 128 also. Will let you know how it turned out.
I’ve tried a few different setups and have yet to find a good solution.
It should be doable but diodes are needed to be used with the intensity signal.
Yes, it seems that the signal coming out of the Amiga is analog whereas the signal that is coming out of the 128 is digital IMO. I did some research and someone had achieved it with diodes as you mentioned but they didn’t share enough info for a DIY’er.
Hi there.
I have done exact like the guide. But i get white pixels that jumps around on screen. Know how to get rid of them? :)
I haven’t experienced any “snow” pixels, sometimes they appear from a too strong signal.
So try tweaking on the RGB potentiometres, try and see if they are still there when the potentiometres are set to 50% rather than 100%.
Continue tweaking with 50% of that.. i.e. to either 25% or 75%, down if the “snow” is still there, up if the “snow” isn’t there.
Much better now. Thanks!
But i think its a bit unstable. Sometimes when i try to start a game from whdload it says no signal. And sometimes it starts perfect. Maybe its not the gbs fault though becuase i tweak Wb alot :).
If you can connect the composite signal to the monitor, then you’ll be able to verify if there’s atleast an output. It could well be the whdload game/demo +settings that causes problems.
I’m glad your “snow” is gone :-)
Hey mate, i have a few questions…
1) Is 5V 2A mandatary ? this circuit dont seems to use 2A.
2) Can be the 5V taken from the DB23 connector directly ?
3) In that case how much current can be taken fron the DB23 connector ?
Thanks in advance…
1. The specification on the board does say 2A, So I wouldn’t recommend that you try with less.. it can damage the supply
2. the 23pin rgb port can deliver 5V, but I wouldn’t recommend it as mentioned in 1.
3. I doubt the 5v can deliver 2A, the specs of an A1200 PSU on the 5v pin is 3A, I suspect only a couple hundred millivolts on the RGB port.
These are not all hard facts, but it’s the best I can give you atm.
This is great! I recently purchased an Amiga 500 and can’t get RF or AV output from the A520 modulator. I’m guessing the A520 is faulty as the monochrome display out works fine. Fingers crossed this solves my problem. I’ve ordered a GBS8200 from eBay and can’t wait to try this. I’ll post my results hopefully within the week depending on delivery time of the GBS.
Cheers :)
Looking forward to hear about your experience :-)
Well i got the converter and it works great!
Very happy with it. Thank you so much for sharing your knowledge Tomse :)
When I made this article I didn’t expect this many comments on it.
I’m very pleased that you all find it useful :-)
For the most part I am happy with this solution for my NTCS A2000. I also upgraded the Denise chip. Then bumped from 2.04 to 2.1 Now I get 1436×460 displaying at 1024×768. A couple of games cannot sync now. I am guessing games that used a different scan rate like pal or something do not work with this converter. The old 1084 monitor used to sync fine with these I tried messing with some utilities to force NTSC etc but no luck.
All in all it is fantastic to have the Amiga out of mothballs. I had forgotten how fun that machine is. I doubt few are finding as much joy getting their 25 year old PC out of moth balls. Does anyone know if I need to purchase a more advance version of this board to get everything working?
I don’t remember how Kick 2.x is, it does have an early bootup though.
In Kick 3.x you can select PAL/NTSC which works fine with my own A2000 with Minimegichip (upgrade to 2mb chipmem, NTSC). I haven’t testet the RGB converter with this machine.
I do believe, if you can change to PAL in the early bootup in your troublesome games, they’ll work.
Some of the games are NTSC or PAL only.
As an alternative, you can try the NTSC version of the games.
You can also try and connect the composite output to the composite in on the GBS. This could probably give the sync signal used.
Unfortunately I’m not aware of any cheap RGB->VGA converters, but there is the indivision ECS which costs more. I have this with my A2000 and the minimegichip, though I haven’t tested all games, it works fine.
Let me hear if any of the immediate tips can solve the sync problems
There are tools in the 2,x realm that handle ntsc to pal and vice versa. I rather suspect the problem is not the ocs to ECS denise or the OS upgrade from 2.04 to 2.1. I think it is the $30 board that take my output from the 23 pin connector and outputs via. I probably need to find an old 1084 monitor and hook it up an I can test that theory. I will post what I find
I won’t deny that it can be the board.
Can you post the games you mention, and also the full specs of your A2000. I’ll see if I can reproduce the problems you have.