Apple II Display issue

9 posts / 0 new
Last post
Offline
Last seen: 1 year 4 months ago
Joined: May 9 2016 - 07:55
Posts: 9
Apple II Display issue

Hi

looks like the first line have sync problem

can someone help?

 

https://photos.app.goo.gl/otFc5moWVudeYXDo8

 

 

CVT
CVT's picture
Offline
Last seen: 18 hours 23 min ago
Joined: Aug 9 2022 - 00:48
Posts: 982
You need to adjust the

You need to adjust the horizontal hold of your monitor. This also happens if the level of the video signal is too low, which is regulated by the potentiometer right next to the RCA video connector inside the Apple II.

Offline
Last seen: 3 hours 37 min ago
Joined: Jun 18 2010 - 13:54
Posts: 734
Could also be due to VSYNC

Could also be due to VSYNC issue (no vertical serrations) if this is a REV 0 board (lucky you!).

Offline
Last seen: 1 year 4 months ago
Joined: May 9 2016 - 07:55
Posts: 9
This is a Rev4 board. I have

This is a Rev4 board. I have already tried the horizontal hold on the mainboard and the monitor, but it didn't help. MIke's page show this error but it only applies to the Rev0 board, doesn't it?

https://www.willegal.net/appleii/applesync.htm

Offline
Last seen: 3 hours 37 min ago
Joined: Jun 18 2010 - 13:54
Posts: 734
tt0ny wrote:This is a Rev4
tt0ny wrote:

This is a Rev4 board. I have already tried the horizontal hold on the mainboard and the monitor, but it didn't help. MIke's page show this error but it only applies to the Rev0 board, doesn't it?

This is true. However, the VSYNC issue was "fixed" again in the REV 7 motherboard (and done correctly this time). So you might need to compare how that change was made. If you're not handy (or willing) to modify your motherboard, then your only other choice would be to find a different monitor that doesn't show this problem. Or get a newer motherboard!

 

Another possible fix would be to run the Apple video through another device to clean up the sync. Try using the video IN and OUT of a VCR for example.

CVT
CVT's picture
Offline
Last seen: 18 hours 23 min ago
Joined: Aug 9 2022 - 00:48
Posts: 982
What is the make and model of

What is the make and model of the monitor you are using? Also is your Apple II outputing NTSC or PAL?

Offline
Last seen: 1 year 4 months ago
Joined: May 9 2016 - 07:55
Posts: 9
I have tried with 3 monitors

I have tried with 3 monitors the result is  the same :(

I from Europe  we have  230/50Hz

 

 

CVT
CVT's picture
Offline
Last seen: 18 hours 23 min ago
Joined: Aug 9 2022 - 00:48
Posts: 982
I also live in Europe. Check

I also live in Europe. Check to see of your Apple II has been converted to NTSC. I have a similar situation with one of my green monitors with my Apple II+ after I converted it to NTSC:

 

 

There is no problem with the same Apple II+ on a different monitor:

 

 

There is also no problem on the same monitor with my Apple II+ clone (Pravetz 82) which is still on PAL:

 

 

This happens on only one of the 7 CRT monitors that I have.

Offline
Last seen: 1 year 4 months ago
Joined: May 9 2016 - 07:55
Posts: 9
that's interesting

that's interesting information about the convert to ntsc. will check soon.

thx

Log in or register to post comments