Q657 (Protechsion zener diode short circuite)and the TV makes a hissing sound. No picture or sound.
Can any one tell me KV-2585 vertical ic number..please...
Posted on May 31, 2013
I am trying to get the code for a universal remote for my sony kv-2785r
. The directions for the remote doesnt seem to be accepted by
the tv. Do you have the code for this model?
Thanks
Posted on Jan 17, 2008
You have your information incorrect, Q is not the designation for diodes, Q657 would be a transistor. First give us the correct number for the diode and how do you know it is shorted?
Posted on Aug 16, 2007
Ok, so you dont have a shorted diode after all, what else confuses me is your heading says KV32FS17 but your text say's KV2585. Now that transistor 2sc4927 is your HOT and if it keeps shorting then I would start checking other things in the Horizontal deflection. I dont have that chassis in my data log so Im just going to take some guesses. Check the flyback, do you have a Dick Smith flyback tester? Check all the electrolytic caps, and check all the resistors. Going out on a limb here I have a log for a KV2785R and I dont know if it is the same chassis or not but look for a resistor R555 if you have it check to see if it is open, if so Sony has an upgrade, let me know if you have that resistor and if it is open, I will give you the upgrade after we find out.
Don
Ok, since I do not have the schematic there is not much more help I can be but I will try. We have determined That Q802 is your horizontal output, But what section is D657 in?? Is that the power supply? Or is it the vertical? Can you tell me? Since you did not answer me about that resistor (R555) I assume you do not have it in that set. Here's what I would do, since D657 shorts out every time you turn the set on I would check every thing associated with that diode, are you sure it is a zener? Check all the resistors in that circuit as well as any other diodes and check the electrolytics. If D657 is in the power supply check the voltage regulator, do you have a stand by B+ with the set just plugged in but not powered on? Let me know and take it from here.
Don
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Sony MODEL KV-2585 TV, everytime the TV is put on, Line Driver Transistor Q802 2SC4927 shorts out.
This advice is 50% helpfull. Sorry I had my information incorrectly reported. The Model is a Sony KV2585.
From your advice, I have almost solved this problem:
Q802 is not shorting anymore, but D657(Protechsion zener diode)shorts out as soon as I switch the TV on. Any clue?
Q657 serves as a 135v regulating zener as well for protection. It is on one of the Secondary output pins of the chopper tranformer,which isolates the power suply on its primary side,and supplkies the rest of the TV with power. As soon asthis is shorted,the set is in an overloaded stage,and thus the hissing sound fromthe transformer,and thus no standby by B+. Because this short is in the primary of the chopper, no fuse breaks,but thus the set is in a protected short. Regrads.
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