CRT

by the way, about my sony tv, big filter capacitor is good! i check smps primary winding with ring tester, 8 leds lit.

Noted.

pwr supply board is separate, when i switch on the pwr supply without load, 470ohm resistor burned besides the posistor, i change the resistor but same thing happen. is posistor have problem?

Did you connect the degauss cable?

smps x’former have regulator ic STR-S5941 but all voltage drop at all output diodes and i change already the regulator ic but still humming sound coming from the smps x’former.

Have you check all components and isolate the power supply?

when checking HOT onboard in crt monitor is the same also in checking on crt tv?

Yes it is the same. Try isolate the section first.

should no reading blk prod to collector(center pin) and red prod iether way?

Yes at x 1 ohm. If you are not sure you can remove it and retest it again.

i check primary of flyback x’former, 8bars lit!

Noted.

and when i check HOT onboard of crt tv, it has reading, but when i check HOT offboard, its good. can you give me a little advice for this jestine? thanks and god bless…

Try pull out the yoke coils cable and remove the flyback and see if the HOT still have reading or not when test on board. Sometimes a shorted secondary winding to primary winding in flyback could cause such problem
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CRT

I trying to fix a 17 Aoc monitor you cannot adjust the vertical size of the monitor I already check the sorounding parts of the vertical defection IC everythings seem to be good I am supecting the IC the original parts is STV9302A I have look to the junk monitor trying to salvage some parts I found out there are two similar IC but the voltage rating is a little bit lower I have two TDA 8172 and TDA 9302H I was wondering if it possible to replace the original with the two that I have found in the junk monitor. Again thank you for your support and time I hope I am not disturbing you.

For ICs, sometimes although have similar spec it won’t run when on load. I have not try that out. Since you got the TDA8172 then put it in and make sure it will not run hot. If it is hot then it can’t be used

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No.1-SAMSUG syncromaster Model no.700IFT.This monitor problem is one horizontal line,the line is not sharp narrowline it is little wide and the desplay is shown.

Check the vertical section-check for supply voltage, corresponding components and replace the vertical output IC and retest.



No.2-PANASONIC MONSTOR,Model no.P70.This monitor problem is color there is only one strog red color.

Compare the red circuit with the green and blue circuit in term of voltage and signal. Any different in the voltage and signal is the clue for you to trace from the circuit point.



No3.-Aopen,Model No.A50V.This monitor problem is power,there is no stundby light,no rely clicking and no B+ voltage to the HOT,but when i measure in the secondury output i fuond three vltages that they do not go further from the secondury filter capacitor,their rate is 32DCV,10DCV AND 9DCV.THANKYOU!



It could be primary power side problem or the secondary side components shorted that had pulled down the voltage. please visit this link to isolate the problem.

http://www.scribd.com/doc/2957819/TT204-Identifying-television-SMPS-problems

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I’ve been repairing CRT monitor for about a year, and one of my customer would like me to repair his CRT TV.

I know you had repaired some CRT TVs from your blog. Do you think it’s easy for a monitor repairman to repair a CRT TV?

It should not be a problem as CRT Monitor have many similarity with CRT TV.

What do you think? I know from the HOT datasheet, some TV are using the same HOT as monitor, is that true?

Yes it is like BU2508AF and etc.

How about the ICs, are they using the same for TV? I’d like to learn something from your experience.

No it is different.

I know that TV has tuner and IF circuit, what are the other circuits that monitor doesn’t have?

Audio/sound circuit .

Venturing into this field means you have to start from the basic of learning TV repair. Get books and visit TV repair forum will be good for you.
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CRT

question for u.

1.Is the s2000af equivalent to st8812fx?

You can try to replace the St8812fx with S2000af but with one condition. After power On make sure the HOT do not get hot after a while otherwise it may blow the HOT. Before replace make sure all the corresponding components are good.

2. A Sinotec TV is switching on, screen becomes bright with horizontal lines. if i adjust the screen switch on the EHT, it switches on and off. Changed some resistors and caps around the EHT but no change. What could be the cause?

Adjusting the EHT voltage too high will cause the screen to switch on and off. Try lower it down the voltage and check the Vertical output IC and surrounding circuit. Look for the blanking signal in the IC and trace from there

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find a connection of the primary

I am trying to repair a Compaq 17″ MV 720 monitor.

I can’t seem to find a connection of the primary of the line transformer to the B+ supply.

Please advise

ANSWER

You mean you can’t find the primary winding of the flyback transformer? Look for the B+ supply input and the collector pin of HOT.
That two points are the primary winding

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