atari 520ste the screen flashes and the system reads for a long time

[libor]

hello

do not you know anyone what might be caused? fdd flashes when reading system and as if it wanted to read. the system is loading much longer while the screen flashes. after booting up, the keyboard does not run, but the mouse can move but the buttons do not work.

 

http://www.libresnet.cz/88/atari520ste/MOV00466.AVI

Thank you

[vattari]

I have come across the same problem with the video before. I was using an ST with a TV over a SCART connection. I ended up selling the TV but I believe it may have something to do with how the sync signal was being generated or the voltage on the blanking signal.

Where did you get your cable from?

 

 

Sent from my iPad using Tapatalk

[ParanoidLittleMan]

I had similar flashing, better said screen/video offs when connected Atari to new Philips monitor via Scart cable, although, offs were much rarer, maybe 1-2 x in minute. I made RGB cable so that Vsync from Atari was used as switch to RGB signal on Scart (pin 16) called RGB blanking. Then just put there instead Vsync +5V via smaller resistor and it became stable and good picture.

It seems that what worked on old, analogue TVs works not well with new ones. Non working keyboard has nothing with video issue.

I guess that using 12 V from ST video out could work on some TVs, but may be that current is not enough (it's limited in ST), that's why used +5V .