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Neil
Neil, Technician
Category: TV
Satisfied Customers: 857
Experience:  More than 10 years experience repairing TV's and electronics equipment.
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convergence problem on Toshiba 50h71

Resolved Question:

left right adjust on red Converg does not function Up/Down ok Blue adjust works all around.
I am An Electronics Technician and have already replaced both Convergence ICs since that has cured the problem on others sets i have repaired in the past.
still the same.
I swapped the red and blue convergence leads off the main board now red adjusts but not blue.
Problem has to be in the external circuit of the convergence IC. Do you have a schematic or know of what components have failed.
This seems to be a common problem in this model.
Submitted: 8 years ago.
Category: TV
Expert:  Neil replied 8 years ago.
Hi,

Thank you for using JustAnswer.

Did you check the six 2-watt resistors beside the STK's? These resistors sometimes burn a bit and change value. These are voltage dividers for feedback. One or more of these resistors has gone up in value, increasing feedback, which reduces maximum gain.

I hope this answers your question and if you have more please feel free to ask.

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Regards,
Neil

Neil and 4 other TV Specialists are ready to help you
Customer: replied 8 years ago.

Found r7726 open 1.8 ohm 2 watt resistor

IC must have shorted and opened this resistor.

 

Thanks

 

Herman Kamphorst ,Ctech

owner/technician

Vast Electronics, Dieppe NB Canada

15 years home/ car audio service specialist