Cherry Master machine

[Mdpokersupply]

Hi all,
 I'm not sure if this is the right place to put this question. I have a customer with a CherryMaster machine and every now and then the screen goes to a single line and I figure its a cold solder joint on the video output. This is a CRT display, am I heading in the correct direction?
Steve

[simeon]

youll find this fault on the 'yoke' of the tube
from it come 4 wires  two are thin two are thick
the thin ones one will have a bad crimp joint or the solder on the plug it attaches too  has developed a discon ring and becomes faulty as the unit heats and cools
even during the day
strip out the monitor pcb and resolder it up fully using lead tin solder
clean the pins of all the plugs using a glass fibre pen from ebay {£6 includes 10 refils}

this fault is called a vertical frame collapse and is related to the vertical diflection circuit

so advice the schematics and check around any ic's associated with it
as mechanical and thermo mechanical movement as well as crystalisation of the lead and tin and breakdown of the solder to separate metals
and to a degree atomic migration
causes dry and broken solders joint to appear  on its pins
usualy the whole row of 10 etc
as most of these boards in monitors chassis are single sided they suffer more

[Mdpokersupply]

Thanks for the info, I plan on pulling the PCB and reflowing the solder around all the pins where connections are made. I think that should take care of the problem.

[fiddlefarter]

Attached is a photo of a vertical IC I have found that they mostly look similar to this, and yes there will be dry solder joints on or around this IC

Regards Sharron

[Mdpokersupply]

Well, I pulled the board and reflowed a few spots that looked a bit bad, as well as, the vertical IC and so far so good. Thanks everyone!

[Mdpokersupply]

Guess what, the problem is back. Does anybody work on these monitor boards, or know a shop that is good with them?

[fiddlefarter]

I would be checking the B+ sometimes this can cause the problem, or you could have more dry solder joints and I would replace the IC I showed you in the pic.

Please let me know if you find the fault Regards Sharron 

[Mdpokersupply]

Thanks, I'll be looking into this more in about a week.