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Title: Cherry Master machine Post by: Mdpokersupply on July 31, 2009, 10:07:16 AM 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 Title: Re: Cherry Master machine Post by: simeon on August 17, 2009, 07:17:41 PM 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 Title: Re: Cherry Master machine Post by: Mdpokersupply on August 17, 2009, 07:46:17 PM 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.
Title: Re: Cherry Master machine Post by: fiddlefarter on August 18, 2009, 12:16:53 AM 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 Title: Re: Cherry Master machine Post by: Mdpokersupply on August 20, 2009, 10:31:35 PM 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!
Title: Re: Cherry Master machine Post by: Mdpokersupply on August 28, 2009, 07:58:37 AM Guess what, the problem is back. Does anybody work on these monitor boards, or know a shop that is good with them?
Title: Re: Cherry Master machine Post by: fiddlefarter on August 28, 2009, 08:31:58 AM 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 :89- Title: Re: Cherry Master machine Post by: Mdpokersupply on August 28, 2009, 09:06:14 AM Thanks, I'll be looking into this more in about a week.
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