Recent content by Goku127

I took a look at the service manual to see what might be the corporate of the problem. I noticed that H Size Control and Distortion Control had a part number listed as Q424~Q431. While Q424 is an iC that is listed in the service manual, Q431 nor something in between does exist. Any idea on that?

I have tried to change the pincushion setting as well. Basically the first picture is the lowest setting on the pot, the middle one is where the corners got more in, while the last one is the max setting at which the corners started to get wavy as well.

So I put a potentiometer in series with the old 33k resistor and got it to the point where the corners were in the picture, but in the middle there was still an indentation so it was still hourglassy. But with really low resistor values I noticed that the illuminated part of the screen was...

Maybe @Mukuro_W has any advice?

This is the best it would get while the hv Potentiometer was cranked at max. At the edges there is still missing one block at either side. Seems to be as bad as the original Flyback, but that one would change its behavior while getting warmer. Not sure what to do next. Maybe I'm going to put a...

Yes they are. I disassembled the potentiometer unit just to make sure they all are functioning correctly. And they do. So turning up the hv voltage would shrink the picture? Or get the corners more in? And how do I know when to stop turning it up?

Now the 33k resistor. Started with a really tiny hourglass picture and while trying to adjust the size it started "wheezing" ? :D. Any Tipps or should I just try in-between the 33k and the 47k resistor.

This is how it looks with 47k still too large

Of course this picture is taken while the h and v size pots are turned to a minimum

Tried it with an 56k resistor and the image is too big :( @nem would you try to put in the 47k or go straight back to the old 33k?

And, which purpose has the second of the three potentiometers on the flyback? It isn't labeled🤔

@nem man you are fast with your replies. If you are already on the forum, maybe any other tips for the first start? What about the potentiometers? On the flyback itself an on the whole board? Thanks in advance Goku

Hey @nem I'm in the process of changing the flyback. One solder pad broke off but I think it's just not connected anyways, since (I hope) it's not a multilayer PCB. I have a bit of knowledge in electronics but I'm still scared as shit with this old-school HV stuff 😅. Can you confirm I can just...

So finally decided to bite the bullet, and I bought a new old stock HR diemen flyback, which was even more expensive than the ones from Technoservice. It should be here by next week. But I heard that even for the HR Diemen one there are some modifications necessary. Do you guys know anything...

Ohh man. I finally would be able to spend about 100€ to fix my stupid arcade screen, but good I looked beforehand into the new posts in the thread. So basically I shouldn't buy the China flybacks? Is there any other option?