Hi,
Does anyone have experience of this amp? I've spent ours trying to repair this amp!
I have several Phonic MAX 860 amplifiers and they ALL have the same problem, more or less!
This is the thing:
If I haven't been using the amplifier for a while it goes in to a "no output/clip mode".
I'll try to explain:
When I power on the amplifier everything seems to be Ok. I connect a 8 ohm dummy load to the outputs. All still Ok.
I connect inputs to a signal source and play some music on low volume and everything is still Ok.
But...
Chrille
Chrille
Last Activity: 02-05-2023, 12:11 PM
Joined: 02-03-2021
Location: Skillingaryd
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Phonic MAX 860 clip / no output
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Re: TV not powering on - with standby red –led flashing
Check this thread out.
[url]https://www.badcaps.net/forum/showthread.php?p=1022048#post1022048[/url]
Another model though but it seems to be a similar problem.
I finally found a bad chip (MP2363DN).
Seems to be a common problem on Samsung TVs.
/ChrilleRe: TV not powering on - with standb...it seems to beLast edited by Chrille; 02-28-2021, 01:07 PM. -
Re: Samsung LE40A676 takes several minutes to start
Hi,
I don't know what you mean with "entire wave form". That's the whole charging cycle. The start is when the TV is off and the end when it's powered on. Nothing more exciting happens later on. If the cap had been bad, I guess there would be a lot of ripple.
Anyway, now to the "solution".
I might be wrong here, but I'm quite convinced that the problem lies on IC1110.
Recently I "fixed" a defective graphic card just by heating it in the owen 15 min in 125 deg C....Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
And here's for you David.p, just to to satisfy your curiosity
The red line is the charging of Cap 1080 when powering on....Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
Thanks you for your commitment, and I'm sorry for not having mension it but I did try to solder a 33uF cap in parallell to the existing 100uF cap, but it was no difference. I've also measured the existing cap and it looks fine.
When I finally tested to heat the just IC1110 with my soldering iron, I'm quite convinced that this is the one!
I agree that it seems a bit strange, and I would not think that this was the the faulty component either, but at the moment, everything points at that direction.Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
My last test by heating with a soldering iron gave me the same result so now I'm as shure as you can get!
I found this one: [url]https://www.digikey.com/en/products/detail/monolithic-power-systems-inc/MP2363DN-LF/5299123[/url]
But there's a "LF" at the end. Will this be Ok to use?Re: Samsung LE40A676 takes several m.../5299123[/url]Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
The 100uF cap seems to be Ok but there is a MP2363DN (IC1110) that I've read from other threads that can be faulty...
At the moment everything points at IC1110. I took my Hot air soldering station and tried to focus the heat on IC1110 only, and when I did that, the TV started.
I can't say by 100% because some air may affec surounding components but there's a big chans that that's the component to replace!
Then I just have to find a place from where I can buy it......Last edited by Chrille; 02-10-2021, 03:23 PM.Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
By heating the marked area I could make the TV start in a few seconds.
Now I can focus on finding the defective component.
Hope I'll be back soon!
...
Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
Thanks for your advices! I went for the easiest test first, which was just to heat up the main board a bit, using a hair dryer, and then try to start the TV.
That was a success!
After heating up the main board a bit, the TV started up immediately!
Does this brings us back to find the "bad C102" on the main board, or do we suspect something else?Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
Yes, I've chacked all fuses and they're Ok.
The voltage on the inverter is 31.7 mV when the board is On/active and 3.4 mV when it's in inactive state.
(I've measured the two STP9NK50ZFP and they also seem to be Ok)
Note: This is when the TV is in the not-working-state, i.e. when it tries to power up but fails.
If I let the TV be on for, say 30+ minutes, it sudden comes to a state when it works. In that state, the inverter voltage is 4.91V.
In this state, everything works fine....Last edited by Chrille; 02-08-2021, 03:44 PM.Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
Since there should be 3-5KV in that cable, I don't want to fiddle too much with that connectors when the PSU is on.
Any way, I'm pretty shure that there is no power in these cables because:
1. There is no working backlight when the PSU is active.
2. I think my electric field detector should detect it.
3. All heatsinks gets a higher temperature when the PSU has been powered on for a while but the one with the high-voltage MOSFET-drivers! (STP9NK50ZFP) This one is "cold as ice"
...Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
I have that as well but it can't measure 3~5KV (See previous results)Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
I guess I should get something here if it's 3~5KV 60khz but the frequency might be too high...?
(I had to zip the movie to be able to attach it)...Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
Ok, but haven't we already found that the backlight doesn't work/light up?
When the PSU starts for 15s, there is no power on the backlight connector witch I guess it should have?
Or is the backlight power controlled separately?
(I guess the image shows the backlight cable/connector, right?)...Last edited by Chrille; 02-07-2021, 12:53 PM.Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
If I unplug the power cord to the main, the PSU won't start because it will not get a "start signal" from the main board... (?)
Anyway, the backlight does not seem to light up. I measured the voltage on, what I think is the backlight cable/connector, and it was zero (during the "try-to-start-up-sequence" with every thing connected).
On my PSU-image above, it's the light-blue and white cable in the left lower corner of the image, beside the two transformers.Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
Yes, all diods checked and they are all Ok.
Since all voltages from the PSU board seems to be Ok and the power is shut of from the mainboard, I would guess the problem is on the main board?
The attached image shows the red power on signal (pin 1) and the yellow is the 13V output (pin 7) from the PSU board.
Here we can see that the power-signal goes low befor the 13V starts to drop....Leave a comment:
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Re: Samsung LE40A676 takes several minutes to start
Hi,
Thanks for your reply!
All voltages seem to be Ok
Pin 1 is 3.69V (Power on)
Pin 2 is 5.0V
Pin 3 is 5.11V (should be 5.3V) Ok
Pin 7,8 is 12.97V (Should be 13V) Ok
Pin 13-16 is 5.07V (Should be 5V) Ok
Pin 19, 21, 22 is 12.96 (Should be 13V) Ok
Other pins are GND on N/C
The power goes up and down in interval.
The interval is 15s high (power on) and 5s low (power off). I get the feeling that it tries to start but fails.Leave a comment:
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Samsung LE40A676 takes several minutes to start
Hi,
I have a Samsung LE40A676 with the same phenomena as these posts:
[url]https://www.badcaps.net/forum/showthread.php?t=73891[/url]
[url]https://www.badcaps.net/forum/showthread.php?t=45913[/url]
Blinking red LED and several minutes to start up.
I have checked the PSU board and there's no visibly bad caps. I have also measured all caps on the PSU board an they all seem to be Ok, just to be shure.
Does any one know if there's a "bad C102" or similar on this main/video board to replace, as the talk about in the linked threads... -
Re: Samsung LN46A500T1FXZA fixed
Hi,
I have a Samsung LE40A676 with exactly the same phenomena.
Blinking red LED and several minutes to start.
I have checked the PSU board and there's no visible bad caps. I have also measured all caps on the PSU board an they all seem to be Ok, just to be shure.
Does any one know if there's a "bad C102" on this main board to replace?...Leave a comment:
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Re: New Members - please post your introductions here
Hello fellows!
I'm a bit in to mixing consoles. Both digital and analog. I've repaired a few.
I also run a sound company and sometimes I make and produce some music.
Have had MSX SpectraVideo and Amiga 500 as well. Recently I repaired a floppy drive to my Amiga.
I'm a professional software developer/engineer but I have big interests in all kinds of hardware as well!Leave a comment:
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