Sync level of 6128+? ***SOLVED***

[Bryce]

The AD724 actually has two separately isolated 5V supplies, one for the Digital part of the IC and one for the Analogue section. The supply can come from one source but it should be a regulated and the converter PCB should have separate smoothing capacitors for each section.

Bryce.

[emuola]

The AD724 actually has two separately isolated 5V supplies, one for the Digital part of the IC and one for the Analogue section. The supply can come from one source but it should be a regulated and the converter PCB should have separate smoothing capacitors for each section.

Bryce.

Ok, thanks Bryce. It looks to me like the pcb has all the necessary stuff. However my external psu:s are both switching psu:s (not sure if that's the correct concept in English), meaning those light cheap ones.

[emuola]

Whadda you know... All the problems were caused by a funky psu of the scart-vga scaler! I never tried other psu:s, because some of my retro computers worked fine with the faulty psu.

After replacing the psu, I really can recommend the following scart (rgb)-vga scaler:

http://www.js-technology.com/store/product.php?id_product=12

Really impressive picture quality, audio out and scart input. I have an additional "force-rgb-mode" switch (because of the missing activation on pin 16). I know it's more expensive than the one mentioned a few posts above, but it's really a plug'n play (presuming you do have a functional psu...) Tested with the following computers:

Amiga 1200
Amstrad 6128 Plus
TG-16 (rgb scart mod)
Philips NMS8235 MSX2

[Bryce]

Congratulations. Never underestimate the effects a "noisy" PSU can have. That really IS expensive for a simple converter.

Bryce.

[emuola]

Congratulations. Never underestimate the effects a "noisy" PSU can have. That really IS expensive for a simple converter.

Bryce.

Yes, I have had a few lessons on "lowsy psu:s" before, but from this own I'll always try another psu, no matter what the symptoms are

I agree on the price However for some reason I could not get a proper image with the combination of the scart switch and the cheaper scaler I'll run some tests with the current scaler and the demos/games that use "tricks" for scrolling etc.  I understood that the cheaper scaler had problems with those (but of course it could be the problem with all the scalers due to the nature of the problem).

[Bryce]

It will be a problem with all scalers. The scrolling tricks all change the picture scan frequency "on-the-fly" which no scalers (not even the very expensive ones) can deal with. Once a scaler has sampled and tuned the picture it doesn't ever check the frequency again.

Bryce.

[emuola]

It will be a problem with all scalers. The scrolling tricks all change the picture scan frequency "on-the-fly" which no scalers (not even the very expensive ones) can deal with. Once a scaler has sampled and tuned the picture it doesn't ever check the frequency again.

Bryce.

Ok, that's what I figured out also. It's a shame that getting yourself a reaally big crt monitor/tv is rather complicated/expensive (freight) nowadays. I have a 28" Philips wide crt tv, but of course it would be awesome to have a 32"/33" crt tv. I just would need to build a separate house for it