WTB: Flicker Fixer

[amigakit]

It is EU law but has global implications.  Now component manufacturers worldwide are complying with ROHS due to it being more economical to make ROHS batches of components.

[Ross1]

RoHS is also law in Canada all new electronics must be RoHS compliant in order to enter the country.
The "Toastscan" flicker fixer was being made by a fairly small production line company and it was no longer cost effective to build due to the difficulty of getting parts.

[murple]

Itd be nice if the schematics were published so that people could try and homebrew new ones. I cant imagine they're very complex devices. From what I've read they seem to mostly work by somehow buffering output in memory and doing a frequency step up. While it may not be cost effective for a company to make them for sale, it may be quite affordable for hobbyists to make their own... considering used ones sell for $200US and more, I can't imagine it would cost more than that to produce.

Things that wouldn't be very acceptable in a commercial product can be fine for home hardware hackers. For example, one of the mentioned issues... "23-pin connectors in right-angle SMD" being hard to get. If I were making a product for sale, I'd probably want it to be on a nice PCB with surface mounted components. If I were making something for myself, I'd be happy with a connector dangling by wires - maybe even one recycled from something else, say, an Amiga monitor cable cut in half.

Homebrew electronics work was a big factor in developing the home computer industry. It'd be nice if that spirit got resurrected for those of us trying to maintain these vintage machines.

[sweetlilmre]

Err, that would have been me (the winner of the auction

I have a Scandex as well, which I can't seem to get to work.
I have heard that this may be a power related issue (or lack thereof), but I haven't had the time to hook up a PC power supply to test the theory.

If anyone has some insight into this, a PM would be much appreciated.

Problem: Plug the scandex in (with power off) connect to the monitor, turn power on. Amiga power light comes on, no further activity.

If I can verify that it does indeed work, I may be interested in selling it.

-(e)

[murple]

What kind of Amiga? Is it an A1200? They come with power supplies that are kind of wimpy. If you use an A1200 with an accelerator and other add ons, it can be insufficient power. The usual fix is to use an Amiga 500 (I think 600s work too) power supply instead, theyve got more wattage.

I got an internal A1200 flicker fixer last week. I cant use it with anything but my 1200 though, and I'd really like an external one that can be used on all my Amigas. If you decide to sell yours let me know... then I'll probably sell the internal I have.

[alexh]

External ones suck compared to the best internal ones.

They have to re-digitise the analog signal.

Digital->Analog->Digital->Analog

You can imagine what that does to the quality.

[sweetlilmre]

Hi,

Yep an amiga 1200 (actually 2 of them). I've tried the Scandex on both, with the heavy type psu and the lighter type psu and no dice. Also tried with the blizzard 1230's removed, still no dice. I'm starting to think I may have bought a lemon.

I will test further as time allows. If anything changes and I decide to sell I'll let you know.

btw. This is my first foray into the amiga world (I've wanted one since I first saw an A500 about 20 years ago) and I have to say the system ROCKS!

[DrDekker]

murple wrote:
Itd be nice if the schematics were published so that people could try and homebrew new ones. While it may not be cost effective for a company to make them for sale, it may be quite affordable for hobbyists to make their own...

If I were making something for myself, I'd be happy with a connector dangling by wires - maybe even one recycled from something else, say, an Amiga monitor cable cut in half.

Homebrew electronics work was a big factor in developing the home computer industry. It'd be nice if that spirit got resurrected for those of us trying to maintain these vintage machines.

The Amiga being a prime example.  Couldn't agree with you more Murple.

[alexh]

It's very easy to make your own 16-bit scandoubler if you REALLY want to.

You need two chips both by Averlogic.

One is a triple 10-bit ADC, the other is the AL250 scandoubler.

A guy called Roy sells ready made ones under the name "CoCo VGA" (because they were originally made for a Tandy CoCo).

http://www.miba51.com/CoCo_VGA_Adpater.html

Bummer is they are only 16-bit, but then so are a lot of Amiga ones.

At $65 delivered they are ok.

[murple]

Oh, sweet! That price is quite reasonable, and 16 bit is fine. 90% of what I'd probably want to use a scan doubler for is WorkBench stuff, since most games/demos use standard Amiga modes and look just fine at default resolutions.

[alexh]

16-bit means that you loose some colour resolution in AGA screen modes (which are 24-bit).

Not a problem if you have an OCS/ECS Amiga, but not brilliant if you have an AGA Amiga.

[vic20owner]

Anyone actually TRIED this scan doubler with an amiga?

Which video modes does it display correctly?

What about interlace?

[murple]

I have an internal flicker fixer in my 1200 (though I havent figured out how to make it fit and still have my hard drive in there, ugh) so I just want one for my A2000. Thanks for the link.

[alexh]

vic20owner wrote:
Anyone actually TRIED this scan doubler with an amiga?

Which video modes does it display correctly?

What about interlace?

I dont think Roy has ever tried it with an Amiga. He recently used it with an Atari ST.

The chips work with all standard TV compatible modes. It is a deinterlacer so of course handles interlaced modes.

Probably doesnt work with Productivity mode etc.

[da9000]

alexh wrote:
One is a triple 10-bit ADC, the other is the AL250 scandoubler.

A guy called Roy sells ready made ones

Do you know if he uses these Averlogic chips in his (Roy's) scandoublers?

alexh wrote:

Bummer is they are only 16-bit, but then so are a lot of Amiga ones.

To make a 24bit one, would you just need a better ADC? If the ADC is 10bits, would that mean it's used for 10bit color (not 16bit, but 1024 colors in a format like 4:3:3 bits for RGB), or would it mean 10bits per channel (RGB), which would then yield, again not 16bit but conceivably up to 10x3=30bit ?

Thanks

PS. I'm with Murple on the "open sourced" SD/FF, and agree fully with the "don't care about RoHS/production pieces" attitude on these things. If it's meant for homebrew, then it doesn't matter. I have plenty of DB25 cable to tear apart for getting my DB23 (just pull 2 pins out  And also, sadly, AmigaKit is right about *why* SD/FFs aren't been made. Jens Schoenfeld gave us the exact same reasons for the lack of SD/FF hardware.

[alexh]

Roy's CoCo VGA contains the Averlogic chips.

The issue is not the ADC (that is effectively 30-bit) but it is the RGB input to the scandoubler which is only 16-bit (5:6:5)

And also, sadly, AmigaKit is right about *why* SD/FFs aren't been made. Jens Schoenfeld gave us the exact same reasons for the lack of SD/FF hardware.

Price is the killer, you HAVE to use off the shelf components to keep the price down. If you are above the $65 (£35) is the "wife acceptable" price point. Anything above that and you have to almost DOUBLE the sale price as you will only sell half as many.

MiniMig has a built in Scandoubler, as does Clone-A so a separate scandoubler project is mute at this point.