k4600 screen "jumping"

[arcadefr34k]

I got a k4600 that randomly "jerks" or "jumps" for a second from left to right then it goes back to normal. I received the chassis and was told it has been fully capped, had width coil fixed, and had resistor R504 replaced. Anyone know what could cause this?

Edit: I hear a "click" sound whenever it does this.

 

[DarrenF]

Perhaps an intermittent connection at the horiz raster postion adjust jumper (P608/J608)?

(assuming that you're referring to "left" and "right" with the monitor on standard horizontal orientation)

 

[arcadefr34k]

Oops, sorry. It is mounted vertically. So it would be jumping from bottom to top. It just did it twice. Almost seems like it wants to start rolling?

 

[DarrenF]

In that case, check the "vertical raster position adjustment" jumper, P604/J604, for an intermittent connection If it's not that, try adjusting the vertical hold pot.

 

[arcadefr34k]

In that case, check the "vertical raster position adjustment" jumper, P604/J604, for an intermittent connection If it's not that, try adjusting the vertical hold pot.

Sounds good. Will pull the chassis this afternoon and look at it. Thanks!

 

[DarrenF]

PS-locations of all of the adjustments & connections are detailed at the bottom of the last page in the manual:

http://arcarc.xmission.com/PDF_Monitors/WG K4600_Manual.pdf

 

[KenLayton]

Be sure to check for cold solder joints at the connector header pins to the daughter cards on the main monitor board.

 

[ELutz]

I'm going with a bad film cap at C621.

Edward

 

[tta583]

I'm going with a bad film cap at C621.

Edward

I am thinking the same thing. Here are the specs.

C621 0.1 uF 1.5KV Paper - Sub in a film

 

[arcadefr34k]

Thanks guys. I am hoping to pull the chassis today. Have been too busy with school lately I haven't had time to do it.

 

[TheDrewster]

Both my GORF and Defender started doing this exact same thing a DAY before the buyers were supposed to pick them up. I will never use a K4600 in any game of mine ever again, but I am curious to hear the resolution to this.

 

[paul400]

Both my GORF and Defender started doing this exact same thing a DAY before the buyers were supposed to pick them up. I will never use a K4600 in any game of mine ever again, but I am curious to hear the resolution to this.

the k4600 does take alittle more time to fuss with but usually some key solder points and a cap kit and they run perfect. I have yet to run in to one with a bad flyback either, they are made like a tank!

 

[ELutz]

Both my GORF and Defender started doing this exact same thing a DAY before the buyers were supposed to pick them up. I will never use a K4600 in any game of mine ever again, but I am curious to hear the resolution to this.

This "click & jump" issue has become a very commom problem with the 4600. Five years ago (I've been messing with this stuff some 17 years), I'd never seen this issue or a bad cap C621........in the last 2-3 years, I've probably seen this issue 10 times......all were caused by a bad cap at C621. At some point, I suspect this cap will become standard fare in a cap kit.

Here's what I use for a replacement.
http://www.mouser.com/ProductDetail/Cornell-Dubilier/940C16P1K-F/?qs=2VJUL6J6vBuS%2bkUt3yG39g==

Edward