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Main => Monitor/Video Forum => Topic started by: twobad on November 14, 2012, 03:02:42 pm

Title: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: twobad on November 14, 2012, 03:02:42 pm

I did a cap kit on a "speedy" MsPac which I believe to be one of the 19K49xx series models.  That solved all the "poor image" issues and worked for about a month.  Now, after a few minutes of the machine being on the screen "slams" to a narrow band as shown in the pictures below.  Bumping on the glass and/or coin door (vibration) may or may not cause the image to revert to normal, only to "collapse into itself" again. :banghead:

I'm suspecting a cold solder joint but would like your opinion on what the likely cause is or if the pictures allow a specific component to be judged as the culprit to prevent unnecessary "work" on an old chassis / machine.

Picture one is the "normal" screen.  The other three are the "collapsed" pics.

Sincere thanks,
-=T=-

Title: Re: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: MTPPC on November 15, 2012, 09:35:47 am

Cold solder joint if vibration affects the failure mode and failure mode is heat dependent.

Title: Re: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: buffett on November 15, 2012, 09:15:43 pm

check all the solder and traces around your vertical transistors Q302-303.

also check the transistors for broken legs i have seen this before.

Peace
Buffett

Title: Re: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: twobad on November 17, 2012, 12:55:09 pm

thank you so very much! :cheers:

Title: Re: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: twobad on November 21, 2012, 07:47:59 am

Q302 and 303 appeared to be intact.  Wiggling C301 that I had replaced during the cap kit revealed a "color change" on the component side of the board without apparent movement of the capacitor.  Reflowing the solder on the "color changing pad"appears to have worked...  I know that's not a good description but I can not think of a better way to describe it- even under magnification when I put pressure on the cap, one of the solder pad edges of the PCB appeared to have "color change"...

Thanks again,
-=T=-

Title: Re: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: buffett on February 01, 2013, 04:45:25 am

just wanted to check if this was fixed.

if not do you still need help.

i could not tell from your last post.

also check out my youtube channel for monitor repairs i have done.
https://www.youtube.com/user/buffett1978?feature=mhee (https://www.youtube.com/user/buffett1978?feature=mhee)

Peace
Buffett

Title: Re: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: twobad on February 01, 2013, 06:54:53 am

You nailed it in your previous post, Sorry I was unclear.  My next door neighbor is in declining health and as soon as I reflowed the transistors, I took the machine to his house and haven't seen it since.  Thanks for the advice and the follow up.  You are "the bomb"!!   :notworthy:

thank you again,
-=T=-

Title: Re: Wells Gardner issue -screen "collapse" WG 19K49xx? Ms Pac Cocktail
Post by: buffett on February 01, 2013, 03:17:42 pm

cool cool happy to help.

glad you got it going for him.

thanks for the clarification.

it helps others as well.

Peace
Buffett