Re: Samsung LE27S73BD - Power board replaced, Inverter caps replaced - No backlight
Good point, I am assuming you mean the FDS8958A mosfets? The only one which is significantly different is the bottom one 'U2'. If I put negative on pin 1 and check Pins 5-8 they are in the 5.5ohm range compared to 2-11 Meg Ohm for the others. Is there anything else ( I see R26 is a 1ohm SMD resistor) that would explain that apart from a short?...
quattro alex
Senior Member
Last Activity: 12-03-2023, 11:58 AM
Joined: 03-19-2012
Location: Kent
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Re: Samsung LE27S73BD - Power board replaced, Inverter caps replaced - No backlight
Just checked and they are all between 0.950 and 0.965 k ohm, so I am assuming that's ok?...Leave a comment:
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Re: Samsung LE27S73BD - Power board replaced, Inverter caps replaced - No backlight
I've just taken the inverter board out of circuit and it appears all of the SMD fuses (marked with a '3') are open.
As a temporary measure for testing only could I use a 3.15a quick blow glass fuse?...Leave a comment:
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Samsung LE27S73BD - Power board replaced, Inverter caps replaced - No backlight
I am in need of a little assistance please. This samsung would occasionally start up but sometimes would take 20 mins or so.
Looking at the power board revealed multiple capxon caps that were bulged and even the small caps had very high ESR. So I replaced all the caps with Panny FC/ FM's thinking this would sort it but unfortunately not. I did a bit more checking and found that the main ceramic resistors were open so I replaced these but still no joy, further checking revealed no secondary voltage at TM801s. I then decided to look at the board P/N BN96-03058A rev1.2 and found a...Last edited by quattro alex; 05-12-2016, 08:00 AM. -
Re: ARCAM AVR500--SAMWHA caps--Unbelieveable!
Lets hope their customer service is better than their choice of caps ( I really hope they don't use those Samwha's in the AVR600)
[URL="http://www.condoraudio.com/wp-content/uploads/Projects/Arcam-CD92-CD-HDCD-Player-Restoration-Repair.pdf"]Here's[/URL] an interesting repair following a previous repair at the Arcam factory.
When you get it back can you do a followup report so we can see how good they are?Re: ARCAM AVR500--SAMWHA caps--Unbelieveable!
Lets hope their customer serviceLeave a comment:
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Re: Panasonic DMR-EX77 with H19 fan fault (unit shuts off)
Base on Q7505 is 0v on standby and when the unit is switched on
Base on Q7511 is 12.27v standby and on, but after 2 mins this drops to 11.62v and 30secs later the device powers down (standby) and the voltage goes back to 12.27v
Emitter on Q7511 is 12.30v standby and 12.27v when on.
Does this confirm an issue with Q7505 or is it further up the line?...Leave a comment:
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Re: Panasonic DMR-EX77 with H19 fan fault (unit shuts off)
Just to confirm I'll be soldering 2 leads, one onto the base and one onto the emitter of Q7511 and then negative lead of DMM will go to ground and the positive will be connected onto the other lead (take reading) , then the swap with the remaining lead?
Thank you for your suggestions....Leave a comment:
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Re: Panasonic DMR-EX77 with H19 fan fault (unit shuts off)
I have 0v from the FANOUT
I have checked resistance values for R7660, R7574, R7540, R7583, R7539, R7538, R7525, R7571 and R7538 they're all correct.
I can confirm continuity between R7660 and Q7505 (bottom left leg)
Will I be able to test those voltages without the other boards connected?...Leave a comment:
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Panasonic DMR-EX77 with H19 fan fault (unit shuts off)
This is a Panasonic DVD & PVR combo that starts up and then shuts off after 30secs or so.
I got the device into service mode and this highlighted an H19 fault ( this relates to the case fan). The was not moving at all, and on closer inspection I found some polystyrene trapped in there. This was removed but the fan did not operate still, I disconnected fan from connection P7502 and tested on 9v battery and this worked fine.
I believe the fan getting stuck might have caused an over current issue at the fan motor transistors Q7505 an Q7511.
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Re: Artic Power 950w - Not 100%
Replacing the diode at D5 was all it took in the end to get this up and running. Thank you to everyone's input in getting this up and running.
Next up I have a Corsair 520w that keeps cutting out on the psu tester, and I have a Goodmans Tv with a burnt connector to the backlight lamps....Leave a comment:
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Re: Artic Power 950w - Not 100%
Thanks for the heads up on the "switchers" I'll take that heat sink out and test them on the DCA55.
Yes, I've got it out of circuit to be sure, but it reads shorted rather than open. Thanks for checking...Leave a comment:
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Re: Artic Power 950w - Not 100%
I've just tested the diodes and found D5 (UF1007) to be shorted ( I get a reading in both directions). Should I replace with the same or go up a notch?
Also can you confirm what you mean by switchers please?
I managed to get around 330v at Q6 but not Q5 does this help at all?
Yes I am very much a fan of AWD and I am on some of the car forums. But if you want to make the most of that system you need the right rubber... Dunlop wintersport 3D's when it gets cold enough
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Re: Artic Power 950w - Not 100%
Escort Eagle - I have checked the switching transistors on the peak DCA55, and they came out ok. Can you advise me on how many volts dc I should be seeing on pins 1&2 of the optocouplers, as when I tested it was only 0.02v dc.Leave a comment:
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Re: Artic Power 950w - Not 100%
No twitching can be seen on the fans, and when I hooked up the multimeter's I am only seeing up to 100mv. I am going to take a closer look at those rectifiers.
The guy didn't mention the spec of the card, and now he's away for a bit, but I'll try and find out....Leave a comment:
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Re: Artic Power 950w - Not 100%
I've got a couple of multimeters, but they're nowhere near the same league as a fluke. However, I'll give this a go this evening.
So I asked the guy how much he had connected and it was a lot.... 5 hard drives, x2 USB hubs, lots of case fans a decent processor, x2 DVD drives and a meaty graphics card. I believe he definitely maxed it out and was sold on the 950w rating,
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Re: Artic Power 950w - Not 100%
LDSisHere I think you have hit the nail on the head there, this was my initial thought when I picked the unit up - it didn't feel that heavy, and when I opened it up I saw the tiny 330uF Capxon primary.
Thank you for this advice - I'll test it and report back...Leave a comment:
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Artic Power 950w - Not 100%
Problem: PSU does not allow pc to start
Testing: Fuse checked fine, primary startup cap fine, ~330v on the primary cap, psu tester does not register anything at all. Apart from the primary voltage I am getting 5.05v at the PS-ON (green lead) and the same at the 5VSB (dark blue lead). None of the other 3.3v or 12v rails have any voltage.
Question: I can't see anything that appears burnt, cracked or smells bad, the caps (teapo) which I know are poor are not bulged and test good on esr meter. Can you suggest where I can test next? ...also can anyone identify the manufacturer... -
Re: Toshiba Satellite Pro L450-12x - Power led on but no display
I did wonder whether it could be that. I ve downloaded the motherboard schematics so I'll attach it here when I get home.... now attached....Last edited by quattro alex; 10-08-2012, 10:26 AM.Leave a comment:
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Toshiba Satellite Pro L450-12x - Power led on but no display
Item: Toshiba Satellite Pro L450-12x laptop
Fault: Nothing is displayed on the screen or via an external monitor through VGA cable
Background: The laptop has over heated several times and on one occasion it has shut down completely.
Initial investigation: Tested on battery only and AC (with and without battery) connected and found power led lights green, battery and AC connected green. I press the on button and the fan starts up at a high speed for around 3 secs and then goes off. There is no disc activity light, but I can hear and feel it working -... -
Re: Dell E173fpf - No led coming on
OK with a little help from the wife I have the following results albeit they seem a bit strange....
1st test:
SMPS:6v initially, then rising to 13v then fluctuating between 13v and 14.2v during this time led light is flashing green constantly.
C857: fluctuating between 12.9 and 14.2v
2nd test:
SMPS 6v initially then rising to 9v and staying there - no led light
C857: Steady around 8.5v
3rd test:
SMPS voltage rose quickly to 15.5v then increased to 16.2v, led flashing...Leave a comment:
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