wg4600 horizontal centering location off

creepykenny

Well-known member
Joined
Jun 24, 2007
Messages
2,817
Reaction score
394
Location
Meridian, Idaho
just recapped this one and now i am unable to get the picture centered - too far left

any ideas? picture is quite nice tho, really good looking monitor

moving location of J608 wire made minimal corrections - ie little to no difference, H centering pot is already all the way turned in the LH direction so no help with it either - i think it is actually about 2-3" off center

pic is done running a 60n1 pos, haven't messed around with a 4600 in many years and i thought it was a bitch to recap ;-)
 

Attachments

  • DSC_4652.jpg
    DSC_4652.jpg
    195.9 KB · Views: 45
Last edited:
those 60n1's don't seem to play nice with alot of the k4600. have you tried it with another board that is not a multicade pcb?
 
thanks, just tried bob roberts adjustments and out come of that was no change to screen location

will try a different pcb and see if that makes any difference

hooked up a jrok-multi-williams and centering is a bit better, but it is still about 1.5" off center to the left
 
Last edited:
thanks, just tried bob roberts adjustments and out come of that was no change to screen location

will try a different pcb and see if that makes any difference

hooked up a jrok-multi-williams and centering is a bit better, but it is still about 1.5" off center to the left

You tweaked L351, the small POT inside a metal can on the daughter board, and the image didn't move at all? That's very strange.
 
yes i tweaked the small pot in the metal can, ... i first centered the lower white nylon pot on the edge of the daughtercard and then rotated L351 until the screen returned to a usable stable state, so yes turning that pot does have an effect, it just did not change the location of the center of the visible raster, i am able to move the center location farther to the right but unable to move it to the left (or centered)

i guess i will take the chassis back apart and start checking the cap values (again)

seems like there something i must be over looking
 
pulled chassis and checked for cold solder, incorrect caps and it all looks good other than the picture being way off center to left

this is what happens when i try to move/adjust the screen to the left

1. turn lower nylon pot on v/h pcb to shift the screen, screen moves to left but loses sync,
2. adjust L351 to correct sync and in doing so the picture shifts back to where we started before, and i repeated this until i reached the stop on the nylon pot with no luck noticeably moving the center of the screen

so am not getting any where with this

any one have any suggestions?
btw, it was near centered before i capped it
 

Attachments

  • DSC_4699.jpg
    DSC_4699.jpg
    192.1 KB · Views: 24
Last edited:
I am having the same problem with a Zaxxon I just bought (WG 4675). The picture had several issues when I got it, off center being one of them. I did a cap kit and the other issues are cleared up, but can't get it centered vertically. Can't get it to go the last inch or so to the right side of the screen.
 
Last edited:
i just ordered another cap kit for mine (from Ian), i will post results, i was checking the caps i had just installed and found one of them to be out of spec, so there may be another in there

so who knows
 
new caps and a search for more broken solder/cracked solder have not made any difference - still unable to move the center of the screen

will have to dig out the schematics and check out the resistors in the Horizontal circuit, i suspect one has been changed to compensate for the old original caps
 
Have you tried a different PCB? 60-in-1's don't seem to always play well with K4600's.
 
i have, and there is only slightly improvement using a jrok multi-williams - it was centered before recapping using the jrok pcb, now picture quality is dramatically improve but centering has been lost
 
have narrowed it down to a problem with the H/V pcb, although i haven't completely figured this one out there does seem to be something off with the little board .... yet
 
Do you have SNYC connected to the negative pins or the positive pins?
 
dug out another board and was able to sync it up (trial & error) and was able to get its video output to get pretty close to fully centered - so thats that with this one (stupid sync issue)

have access to another 46xx chassis and plan to do some tests / swaps and see if i can nail it down further - now i need to repair the second 46xx chassis

one thing of note is the resistor R351 which is a 2.2K on schem and on this board is a pair of 2.2k resistors yielding a 1.1k total (this is strange and does seem to effect the centering a bit) have another vert/horz board that does have only one 2.2K resistor and its centering is a bit off using same test board

B+ voltage is around 127/128 so thats good

now to repair the next ones
 
Last edited:
Back
Top Bottom