Recent content by demonlg

Yes, found a defective UC6 74ls374 dave! Now is ok. Wow It's time to revive drives unit now.....

With PETTESTER it's pass first 2 test and going to countdown and then ram test.

Hi Dave, i have repaired the video board and now i have a video image in photo, probably any issue in char rom section or ram. The char rom is good. Any idea?

Yes, I remember that we also took them for the other 8296, in fact I tried to do the same measurements as in post 15 of the other discussion, but what I get is what I posted, and it's the same thing with both PETTESTER than with the original EDIT.

Hi Dave, I can't possibly set my scope as you asked, I really don't know how to do it, the only thing I can see is what I attached in post 15, I just can't. Tomorrow I will probably be able to reassemble the screen, I had to replace a diode which was completely detached due to oxide on the...

So, let's go step by step, let's take the first step first, this is vdrive, is what I'm viewing in this photo what you're asking me about vdrive?

Sorry Dave but is correct this? Make sure the YELLOW VDRIVE signal triggers on the LOW to HIGH part of VDRIVE. or Make sure the YELLOW VDRIVE signal triggers on the LOW to HIGH part of HDRIVE. I don't know why i don't understand ! :D

Sorry for my mistake but I thought I did it right in the last image, I'll try again later

It's normal video signal is 60hz and in other post of 8296 repaired i have 50hz? Different rom?

I don' know if i understand but now i have restarted test with your pettester rom inserted, i have connected on ch1 yellow the vdrive signal with two negative pulse by move time base to 2ms, then i have connected ch2 cyan on video signal, and i have this. In the video you see the pulse on ch1...

This is the yellow video signal and cyan vertical drive in video 194153 and with horizontal drive in video 194550.

Ok, i have to chop the video signal with H and V drive? This night i reassemble the monitor board and send you photo of screen.

What do you intend with black and white? Sorry

Little video clip 161049 is VIDEO signal 161127 is VERTICAL DRIVE 161205 is HORIZONTAL DRIVE This is with original EDIT rom installed. (NOT PETTESTER!)

Ok, i have to reinstall CRT board on the CRT and i send you image of screen, now i have only possiblity to send scope trace.