help with a520 s-video hack

[Damiga]

Hi,
 
I've spent last two days following these instructions: http://members.iinet.net.au/~davem2/overclock/a520.html
 
Is there someone else here that has done it?
I need some assistance because I cant get it to work.
 
I've lost count on how many times I've gone through the instructions and checking that I've followed all the steps.
 
Help?

[Franko]

Had a look and it seems pretty straight forward enough, though I didn't think anyone would actually be using an old a520 these days...

Not sure why your using it or needing to convert it to an S-Video signal (RGB is much better) but if you do need S-Video it may be simpler to buy a ready made Composite to S-Video converter box...

[Damiga]

Had a look and it seems pretty straight forward enough, though I didn't think anyone would actually be using an old a520 these days...
 
Not sure why your using it or needing to convert it to an S-Video signal (RGB is much better) but if you do need S-Video it may be simpler to buy a ready made Composite to S-Video converter box...

Well I wasn't using it and I wanted something to do =)
 
Normally I use an old CRT with SCART connector, but I also have a projector that hasn't got SCART. The projector has Y-U-V connections so about a week ago I bought a second hand SCART->Y-U-V converter so I could hook it up.
 
It gives a nice sharp image but unfortunately there are som slight vertical "ghosting" of the colors.
 
So since I had an A520 that was of no use to me I decided to give it a try and see if the converted A520 would produce a better image than my scart-yuv converter

[Damiga]

And by the way...
 
You should know better than to ask a geek why he tries to do something.
The answer is as always, "because I can" =)
 
Although in this case, I couldn't :/

[magnetic]

As far as a520 svideo hack thats a nice project, too bad it wont work for NTSC a520s according to the doc? or can it..

@ op when you say "not working" what exactly do you mean? just a black screen? are there scanlines or color?

[Franko]

Franko

completely useless post as usual why bother posting on every thread. And what kind of moron tells somebody to run a composite to svideo adaptor that ruins the whole point of having y/c.. wake up. Every time you post a stupid post like this I will be there to tell you to stop the insanity. You are growing tiresome to productive amigans.

As far as a520 svideo hack thats a nice project, too bad it wont work for NTSC a520s according to the doc? or can it..

@ op when you say "not working" what exactly do you mean? just a black screen? are there scanlines or color?

Go take a run

[Franko]

And by the way...
 
You should know better than to ask a geek why he tries to do something.
The answer is as always, "because I can" =)
 
Although in this case, I couldn't :/

True... but it would be simpler to buy a Composite to S-Video convertor to use with a projector or better still an RGB to S-Video convertor for a really clean picture...

As for the hack, one of my mates did a similar hack years ago on his old A520 as at the time he didn't have a monitor and the TV he was using only had composite & S-Video connectors, I recall though that the picture quality was quite poor though...

[Damiga]

Franko
 
completely useless post as usual why bother posting on every thread. And what kind of moron tells somebody to run a composite to svideo adaptor that ruins the whole point of having y/c.. wake up. Every time you post a stupid post like this I will be there to tell you to stop the insanity. You are growing tiresome to productive amigans.
 
As far as a520 svideo hack thats a nice project, too bad it wont work for NTSC a520s according to the doc? or can it..
 
@ op when you say "not working" what exactly do you mean? just a black screen? are there scanlines or color?

Just a black screen and the projector displays "no signal".
I tried flipping the C and Y connectors just in case I wired them wrong, but then the projector goes crazy, fans spinning up =)
 
I was thinking that maybe there are som crucial points on the circuit board that I should measure and compare with someone that has a working s-video hacked A520

[Damiga]

True... but it would be simpler to buy a Composite to S-Video convertor to use with a projector or better still an RGB to S-Video convertor for a really clean picture...
 
As for the hack, one of my mates did a similar hack years ago on his old A520 as at the time he didn't have a monitor and the TV he was using only had composite & S-Video connectors, I recall though that the picture quality was quite poor though...

I'm not looking for the easiest way :laughing:
 
I have composite on the projector but the image quality is not so good, and my A500 only gives b/w on composite so it's not really an option for me.

[Franko]

The hack my mate done years ago wasn't as complicated as the one you posted the link for he basically traced the RGB inputs on the A520 and followed them through to where they were combined on board the A520 to feed the signal to the RF output...

From there he simply tapped the connections via a couple of resistors & caps to get the Chroma & Luma signals, as I say it worked but the picture quality was no that great (it had some ghosting that he could never quite get rid off)...

He's not at home just now but I've emailed him to see if he can recall exactly how he done the mod, doubt he'll remember though cos he's been out of the Amiga scene to about 10 years now but you never know...

[desiv]

The answer is as always, "because I can" =)
 .....
Although in this case, I couldn't :/

Well said, and I had unfortunately similar results when I tried an NTSC variant I found on the web...
I did get some picture, but no color and it wasn't even good b/w...  :-)
It was fun trying, but I eventually picked up an s-video adapter...

It's great to succeed, but it's fun even when it doesn't work..

desiv
p.s.  I was able to save face (to myself, I believe in lying to myself) because when I opened the NTSC 520, it was obvious someone before me had done some major work..  Replaced chips, etc..  So I was able to blame the previous tinkerer..  ;-)

[magnetic]

@ OP

Try with a regular tv or monitor not the projector.

[Retro_71]

I have built one of these about 4 - 5 years ago when i didn't have that many monitors.

It was painful but it worked.
I know it sounds silly but have you followed all the instructions properly?
I would check to make sure all your cut and hacks were right.
Have you tried this on another TV (could be the projector doesn't like the A520?)
I will have to dig through my boxes to see if i can find again (if you want me too).

This is actually a nice mod to do if you only have TV (without SCART) to work with much better picture than a stock A520.

P.S.
I assume you double check all your orientation of your resistors with the colour image?

[magnetic]

@ op

Most good projectors have a vga or rgb input as well (or component) maybe something along those lines?

[Retro_71]

You don't remember you turd? i guess that you wouldn't since it must be part of how you are let just say a certain 060 for a A1200...

As for staying at home and typing LOL that funny well if you ever get to Sydney come over I will more than happy to have you spend the rest of your stay here in hospital.

Don't assume just because i am a nerd that you know what I can or can't do or have done.

Anyway enough with the Hijacking of the thread.

The Mod works you just have to be extra careful, maybe because i am not that good (back then) with the soldering Iron i was always triple checking what i was doing. Then again maybe that projector doesn't like the A520 or some component is broken/burnt?