Re: 12V rail is not on ?
I've fixed it,DONE
12V rail is not on ?
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Re: 12V rail is not on ?
Since you bought some new rectifier diodes for replacement, did you test it with your tester to see if the Vf comes out the same as the spec sheet as tested per TEST CONDITIONS?Leave a comment:
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Re: 12V rail is not on ?
BTW, I am not the only that already pointed out to you about the test conditon:
https://www.badcaps.net/forum/showpo...&postcount=144
Quote:
Originally Posted by bianchi77 View Post
I got bad 2N60, C = 1.06 nF...on the datasheet, maximum = 350 pF
That's because your transistor tester probably applies different test voltage and current.
Also, you don't need a transistor tester to check transistor. Should be able to do this with a multimeter.Leave a comment:
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Re: 12V rail is not on ?
Look at the test condition.
Well, did you look at the test condition as per spec sheet of the transistor and compare to what your tester using , since it is not the same then how can you are saying it is testing with the same test condition as the spec of the transistor was tested on.
You are NOT comparing the same test condition, so if you believe your tester then you will probably believe you have lots of bad parts then. It is UP to you to believe your tester or not.
Manufacturer put what test condition is done to provide the spec of the device, if you do not test at the same condition then the the end user cannot complain that the device does not meet the published specification, common sense.
Test Condition:
5V, 0.8A
5V 4A
5V 1mA
So are you telling me that your tester is applying all those Voltage and current?Last edited by budm; 10-14-2016, 07:25 PM.Leave a comment:
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Re: 12V rail is not on ?
Out of circuit or in circuit. You always need to specify this.
That's because your transistor tester probably applies different test voltage and current.
Also, you don't need a transistor tester to check transistor. Should be able to do this with a multimeter.
Like I said, I don't think anyone does. Or even if someone does, don't expect them to join this forum just to post it here. Work with what you have. This is a very very basic ATX PSU. If you don't understand how this PSU works without schematic, you need to step back and read/learn more about circuits and components.
And again, I will ask you once more:
PLEASE! Put all your 1-line, 1-sentence posts into a single post. We are already at page 8 here, and the thread is a mess. I am already forgetting what was tested and what wasn't. If this keeps up, I'm not going to be able to help you any further with troubleshoot this PSU.
Yes I keep learning about circuit and components that's why I keep fixing...
I put 1 line, 1-sentence, because it's a progress...and I can't put all together at once...I've forgotten already if I try to remember what I had done...too many small things on fixing circuit...some kind of step what I had done..Last edited by bianchi77; 10-14-2016, 06:46 PM.Leave a comment:
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Re: 12V rail is not on ?
Can you show us how you set up your test equipment to do the test as shown in the spec sheet 'TEST CONDITIONS'?
Remember how you are telling us the diode is bad because the Vf did not come out as shown in the spec and we had to explain to you how to read the spec sheet and how to test it per spec sheet? It sounds like you still do not understand or learn from that experience as to what the spec sheet is telling you.
5.1.2 Measurement of NPN Transistor or N-Channel-MOSFET
That will answer you about "TEST CONDITION"...if you 're not sure, it's up to you...Leave a comment:
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Re: 12V rail is not on ?
You are joking, right?
You mean your tester is putting out those exact test condition as shown in the spec sheet? How did you set up your tester to put out those Voltages and frequency? Do you really have that kind of test equipment? I thought you bought one of those $20 tester.
I doubt that your tester can really do it as test condition.
So where are the other two Capacitance readings?
one parameter is enough to decide...if you want to get all the parameters...you can have it but you need a better tester which expensive and only affordable by a big company which has a profit from it...
for me I don't get any profit from it, only learning and curiousity...Leave a comment:
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Re: 12V rail is not on ?
You know what you can really do, get it over with and replace all the parts to get it working and put old parts back in one at a time until it stops working.
Did you even try checking you new spare parts to see any of them meet the spec sheet based on the measurement using your tester?
'I see a faulty on Q4,Q3,Q2,Q1, D9 board' based on your tester because the Beta of the transistor did not come out as shown in the spec sheet?
What do you want to do for fixing anyway ? I want to know...replacing all the components by new one ?buy a new one then...easier...
Last edited by bianchi77; 10-14-2016, 06:32 PM.Leave a comment:
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Re: 12V rail is not on ?
I've checked all of the components one by one off board....Leave a comment:
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Re: 12V rail is not on ?
Can you show us how you set up your test equipment to do the test as shown in the spec sheet 'TEST CONDITIONS'?
Remember how you are telling us the diode is bad because the Vf did not come out as shown in the spec and we had to explain to you how to read the spec sheet and how to test it per spec sheet? It sounds like you still do not understand or learn from that experience as to what the spec sheet is telling you.
Have a read about test condition:
http://www.mikrocontroller.net/artic..._.28English.29
chapter 5...that's the way the transistor testedLeave a comment:
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Re: 12V rail is not on ?
BTW, what happen to the bad IC with reading of 300 Ohms on the Open Collector output pin and GND?Leave a comment:
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Re: 12V rail is not on ?
Can you show us how you set up your test equipment to do the test as shown in the spec sheet 'TEST CONDITIONS'?
Remember how you are telling us the diode is bad because the Vf did not come out as shown in the spec and we had to explain to you how to read the spec sheet and how to test it per spec sheet? It sounds like you still do not understand or learn from that experience as to what the spec sheet is telling you.Last edited by budm; 10-13-2016, 10:06 PM.Leave a comment:
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Re: 12V rail is not on ?
You know what you can really do, get it over with and replace all the parts to get it working and put old parts back in one at a time until it stops working.
Did you even try checking you new spare parts to see any of them meet the spec sheet based on the measurement using your tester?
'I see a faulty on Q4,Q3,Q2,Q1, D9 board' based on your tester because the Beta of the transistor did not come out as shown in the spec sheet?Last edited by budm; 10-13-2016, 09:47 PM.Leave a comment:
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Re: 12V rail is not on ?
You are joking, right?
You mean your tester is putting out those exact test condition as shown in the spec sheet? How did you set up your tester to put out those Voltages and frequency? Do you really have that kind of test equipment? I thought you bought one of those $20 tester.
I doubt that your tester can really do it as test condition.
So where are the other two Capacitance readings?Last edited by budm; 10-13-2016, 09:50 PM.Leave a comment:
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Re: 12V rail is not on ?
Out of circuit or in circuit. You always need to specify this.
That's because your transistor tester probably applies different test voltage and current.
Also, you don't need a transistor tester to check transistor. Should be able to do this with a multimeter.
Like I said, I don't think anyone does. Or even if someone does, don't expect them to join this forum just to post it here. Work with what you have. This is a very very basic ATX PSU. If you don't understand how this PSU works without schematic, you need to step back and read/learn more about circuits and components.
And again, I will ask you once more:
PLEASE! Put all your 1-line, 1-sentence posts into a single post. We are already at page 8 here, and the thread is a mess. I am already forgetting what was tested and what wasn't. If this keeps up, I'm not going to be able to help you any further with troubleshoot this PSU.Last edited by momaka; 10-13-2016, 09:18 PM.Leave a comment:
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Re: 12V rail is not on ?
I see a faulty on Q4,Q3,Q2,Q1, D9 board = Y-B200ATXLeave a comment:
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Re: 12V rail is not on ?
on ATX LEC-011 REV 1.2 I've found 2SC2335 as a resistor...it's no more transistor on test device...Leave a comment:
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