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Old 27 July 2020, 19:47   #21
SquawkBox
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Very well, so let's focus on the VGA output of the riser, also let's assume it is actually a 15 Khz type of signal. With your current setup, you're telling me the best you can do in terms of playing Amiga games is displaying the Workbench under certain screen modes and play games that would run from there ? Pretty limited in scope. Have you considered getting one of these (prone to failure ? Rumor has it) 13'' or 14'' 80's CRT's (1084S...) that are 15 KHz enabled, to the best of my knowledge ?

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Old 27 July 2020, 19:58   #22
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I have trinitron sony in my cave but I want to put cd32 in living room. I can get picture over rca but its ugly.
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Old 27 July 2020, 21:17   #23
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Time to invest in one of these maybe.
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Old 27 July 2020, 23:01   #24
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Its price is a bit ridiculous. I'd rather buy Vampire.
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Old 28 July 2020, 01:15   #25
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How do you guys interpret this?



What would rgb(v) be? And would you trust them that input can be 15khz?

https://m.aliexpress.com/item/327722...608555f&is_c=N
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Old 28 July 2020, 03:37   #26
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They are confused what their own product does.
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Old 28 July 2020, 09:58   #27
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Quote:
Originally Posted by Cobe View Post
Its price is a bit ridiculous.
You get what you pay for, I guess. Up to you to settle for some 2-in-1 Chinese engineered pos (as Indivision folks explain it, plain line doubling just won't cut it for LCD, 'cause 50 Hz and stuff). This said, you could also try to get hold on a VGA box similar to mine, it bears VGA input among others, I would go as far as saying it's a God sent, check its specs here. Got it from some young dude for 50 euros, complete with its connections and remote. I may contact the above mentioned scanline generator seller to ask them whether their device does support 15 KHz signal or not, if you want me to (pretty confident it does).
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Old 28 July 2020, 23:51   #28
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Well that would be nice if you'd ask them to clarify if device accepts 15khz and if it does whats its output frequency in that case. Also they could confirm if device works in 50hz or 60hz or both.
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Old 29 July 2020, 08:33   #29
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I've tried scanline generators straight between the RGB 15KHz and monitor. The problem is the scanlines will be way too thick. Will not look acceptable at all.

You need 31KHz to add proper scanlines. Once you have 31KHz signal then the scanline generators will work correctly and give nice scanlines. 50 or 60Hz will not matter. They will add scanlines the same way the built-in scanlines in products like Indivision ECS/ECS V2 or AGA MK2 will. You could even use a scanline generator on any of of these and they work perfectly.

Edit: I've seen scanline generators advertised as 15KHz compatible. This is a bit false advertisement as the scanlines is way too thick as I've said.

Edit 2: On a unit like Indivision ECS V1 it can make sense to use a cheap scanline generator. Because the ECS V1 only has one built-in setting for scanlines. Which is quite dark scanlines. With a scanline generator one can adjust the brightness of the scanlines.

ECS V2 and AGA MK2 has various brightness settings for the built-in scanlines.

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Old 30 July 2020, 18:52   #30
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Just got a reply from r2tronik. It's rather straightforward, but I'll translate it anyway :
"Assuredly, it's conceivable. The scanline has the ability to deal with many frequencies, ranging from 0 to 1 000 Hz, so there should be no problem at all."




though in my opinion, you have a bigger problem with the constraint of using a LCD without resorting to some kind of line doubling device. For the record, here is the bit of trivia from the AGA MK2 product sheet :
Quote:
The first flickerfixers for the Amiga have already been available 17 years ago. Since that time, all flickerfixers have been using the same principle: The picture frequency was doubled. This is not enough for most modern VGA monitors and TFT displays, as the picture of a computer with PAL standard was only displayed at slightly less than 50 Hz. Most monitors require 60 Hz or more these days. Indivision AGA goes a new path. As the name suggests, it's a flickerfixer that is very closely tied to the AGA chipset. This could only be achieved by putting the flickerfixer inside of the computer. The product is mounted over the video chip Lisa. The VGA display is connected directly to the flickerfixer.
One thing to have in mind is that the scanline genrator won't give you any trouble, I could vouch for that. turrican9 post makes sense though, above reply doesn't imply that in 15 KHz mode the scanlines themselves will please the eye, just that they will be displayed.

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Old 30 July 2020, 19:16   #31
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Ok, thanks guys!
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Old 31 July 2020, 21:23   #32
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Thanks to you too. Now, I will be more cautious before considering getting a CD32 or suggesting someone to get one.
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Old 13 August 2020, 22:08   #33
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Probably not of interest to any of you, but I know my GBS 8220 with GBS control firmware installed allows you to generate scan lines and have various levels of doing so.

I don't really get it myself, is it to emulate the lines from a CRT right?

If I was to show any example of these to you what would be the best way for me to capture the screen other than using my phone?
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Old 14 August 2020, 00:20   #34
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Yup, its to "emulate" lines from crt.

Phone's fine, probably nothing is good enough to do justice.

But did you mod your gbs yourself? I didnt find one(with gbs control) readily available to buy anywhere.

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Old 14 August 2020, 02:24   #35
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Yup, its to "emulate" lines from crt.

Phone's fine, probably nothing is good enough to do justice.

But did you mod your gbs yourself? I didnt find one(with gbs control) readily available to buy anywhere.

Yes that's correct. I bought an Arduino board, then flashed the the firmware to it. Once I had done this I installed to my gbs 8220.


I will take some photos tomorrow.


People sell the gbs control pre made however it is so much cheaper to do yourself.


I bought Arduino board for another £5 so total cost was £20 including the cost of the the 8220 board. Works great with my 32" sharp TV.
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Old 14 August 2020, 13:55   #36
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People sell the gbs control pre made however it is so much cheaper to do yourself.
Anywhere in Europe? I'm interested since apparently it can also serve as a downscaler.

I've actually impulse-bought a cheap scanline generator some time ago. It looks very similar the one in Cobe's pic. But I thought it's for a PC VGA (31khz)output signal because the seller said it was connected to his VGA monitor. I've never got around to trying it yet thou...
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Old 14 August 2020, 21:53   #37
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People sell the gbs control pre made however it is so much cheaper to do yourself..
Hm.. you made me reread that gbs control install instructions and now they look a little less intimidating than the first time i read them. Though I'll have to watch video too to see if I'm up to the task cause my soldering skills dont go much further from soldering cables for the guitar..
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Old 17 August 2020, 13:37   #38
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Quote:
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Hm.. you made me reread that gbs control install instructions and now they look a little less intimidating than the first time i read them. Though I'll have to watch video too to see if I'm up to the task cause my soldering skills dont go much further from soldering cables for the guitar..
If you need a hand just let me know. It does read more complex than it was.

I have pics of the scan lines.

There a extreme levels of scanlines which you can have by themselves. Then you can use a line filter which makes it suddenly appears better and more like a monitor. Honestly though it doesn't look as good on my phone. Post pics shortly.
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Old 17 August 2020, 13:49   #39
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no scan lines



some scan lines but with the line filter on



also line filter on but stronger scan lines setting



below then are examples of varying scan line extremes and without the line filter on











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Old 17 August 2020, 14:10   #40
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Just got a reply from r2tronik. It's rather straightforward, but I'll translate it anyway :
"Assuredly, it's conceivable. The scanline has the ability to deal with many frequencies, ranging from 0 to 1 000 Hz, so there should be no problem at all."
Yes, the scanline generator will dim every second scanline no matter what the frequency.

In a 15kHz source, every line is sent exactly once. If you add a generator to a signal like this, you will dim / lose every second line of the source signal. This is NOT what old CRTs did, they stretched the image out vertically to a 4:3 ratio so that there was nothing but blackness between the scanlines.

The point here is, that the 15kHz source gets doubled to 31kHz, which means every scanline will be shown twice, and they look too thick and solid now, because the black that used to go in between the lines now contains a copy of the line above it, not blackness. The aspect ratio is still 4:3, double the amount of lines is displayed using the same physical area, so naturally they are closer together and more "solid".

Now a scanline generator makes sense: it will dim or totally black out the second line of the identical pair, giving you the same effect as a 15kHz 240 or 288 line image stretched to 4:3.
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