Re: Harman Kardon Soundsticks III Bad subwoofer, low bass
Interesting thought on the PSU, I'll take a look there and see if anything looks off. I'm assuming that the caps fail, it should be visually obvious?
This is the model with a single 3.5mm out, so jack plugs....
viewfindr
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Last Activity: 10-29-2023, 03:24 PM
Joined: 02-24-2019
Location: San Francisco, CA
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Harman Kardon Soundsticks III Bad subwoofer, low bass
I have a pair of rarely used computer speakers. Recently, I noticed that the subwoofer was barely working. Both satellites are still good, but even when turned up all the way, the subwoofer is extremely weak and produces almost no bass. It definitely still outputs a little bit on the deepest notes, but is far from what it should be.
I took it apart, and the subwoofer driver measures about 17 ohms on a multimeter. I couldn't get figure out how to get the board out, but attached some photos (cables attached are affixed to the housing). The caps look good to me (no bulging or leaking),... -
Re: Display panel not working - Sony STR-DN1080
Wow, sharp eyes! You're right - I resoldered the joints between the display and the board, and it works now. Thanks so much, I've learned that I need to look more closely on some of these solder joints.Leave a comment:
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Display panel not working - Sony STR-DN1080
I have this receiver which works great - on screen GUI and all channels of audio are carried through, but the front display has stopped working! Confirmed that it's not a dimmer setting issue.
Searching around, it seems like this has happened to a few other people, but not super widespread. Others have [URL="https://community.sony.co.uk/t5/home-cinema-projectors-players/str-dn1080-display-panel-not-working/m-p/3740136/highlight/true#M19070"]mentioned that applying pressure[/URL] causes the display to come back, but this hasn't worked for me. Tapping it in the right place...Last edited by viewfindr; 02-28-2021, 02:04 AM. -
Re: Help diagnosing no backlight and no picture - Wasabi Mango
Yep, definitely the backlight. The set worked fine for about 5 power cycles, but now it's not lighting up again. Seems odd that it's temperamental, but I guess I'll have to take apart the panel and start testing the bulbs individually now.Leave a comment:
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Re: Help diagnosing no backlight and no picture - Wasabi Mango
I think you're right - I kept clicking around in the menus to see if it was visible, and started to see text at a very precise angle - very hard to find!
Miraculously, the TV suddenly lit up while I was doing this. It seems to be working as normal now, not really sure why - nothing was really changed during this time, and connections are the same. I noticed the back panel was a little warm, so could it have needed to warm up?
Still perplexed at why.. I checked pure white...Leave a comment:
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Re: Help diagnosing no backlight and no picture - Wasabi Mango
There is no "label" per se, just a plastic shield behind the components on the back and where it's mounted against the metal back of the panel.
I've attached another angle of the back of the board, where it's more visible and the top pin outs are clearer. Is there anything else I should look out for?...Leave a comment:
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Re: Help diagnosing no backlight and no picture - Wasabi Mango
Any additional thoughts? Would it be possible to verify the backlight is working by shorting some of the pins on the psu directly?Leave a comment:
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Re: Help diagnosing no backlight and no picture - Wasabi Mango
Sharp eyes! I think it's just a bit of debris - I was able to remove most of it with tweezers.
Here are the rest of the readings:
PS-ON: 3.1V
BK/ON: 5.1V
ADJ (I think, pin right above BK/ON): 4.7V
All of these measured about 20-50 mV when TV is powered off. Side note, I just noticed that the optical audio out port lights up when powered on, so it seems like unit is receiving adequate power?...Leave a comment:
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Re: Help diagnosing no backlight and no picture - Wasabi Mango
Just took some measurements on the PSU - 5VSB line was about 5V with tv off, and measured 12.97V on the +12V line and 5.5V on the +5V line both on the bottom section and top section cables when powered up. Doesn't look like 24V pins are hooked up.Leave a comment:
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Re: Help diagnosing no backlight and no picture - Wasabi Mango
Photos attached below. Thanks for the pointer to look behind the board. I'm guessing my next step will be to test the 5V and 24V outs to see if they're high when the power is on?
There's unfortunately this plastic backing piece which is attached with pins that's rather hard to remove from the power board....Leave a comment:
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Help diagnosing no backlight and no picture - Wasabi Mango
Hi there, I have a rather interesting looking set of boards in this Wasabi Mango U400UHD TV (korean OEM), not much information available online.
The components inside appear to be a mismatch of OEMs - the power board comes up as an RCA part? The TCON has Samsung logos on it, and there are no real identifiers on the mainboard, which I think is a generic part?
Either way, I'm not getting any indication of life now, aside from the power LED changing colors and the startup chime. The shutoff chime seems to be gone, although the LED does change from blue to red when shutting... -
Re: Vertical lines on a Samsung UN60ES8000 - salvageable or bad panel?
I've read suggestions online to heat up the edges near the tab bonding boards and apply pressure. Is this worth a try, or is the panel just toast?...Leave a comment:
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Vertical lines on a Samsung UN60ES8000 - salvageable or bad panel?
I have one thick vertical line right in the middle, along with a few smaller lines about 1 px wide of various colors.
I understand that this is most likely a defective panel? But wanted to rule out a bad tcon or LVDS cable just to be sure there's no hope before tossing it. I've read that this model has a built in tcon test pattern accessible via the service menu, but I wasn't able to see any difference on screen while scrolling through 0-18 of the patterns, unlike the mainboard test patterns.
My question is: is the screen supposed to change when viewing built in...Last edited by viewfindr; 01-24-2021, 02:09 PM. -
Re: Samsung UN46D6500VF - no display, odd lines and double image on half of display
I covered the 5-6 pins around the VSS point on the tcon with clear tape and can only get white bars to show up on the screen. Since this is the case, I assume that this is a lost cause and it's not worth trying a new tcon?...Leave a comment:
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Re: Samsung UN46D6500VF - no display, odd lines and double image on half of display
Do you have any suggestions on which part of the connector to block with tape? I see a VSS test point on the board, but am not sure if the area to try would be the connectors right underneath it?...Leave a comment:
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Re: Samsung UN46D6500VF - no display, odd lines and double image on half of display
Sorry for the delay, but I finally picked this project up again and took some new measurements on the tab bonding board with a new multimeter.
All caps measure between 3-6 kOhms on both sides. Is this variance expected? Does this mean that the panel is actually okay?Leave a comment:
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Re: Samsung UN46D6500VF - no display, odd lines and double image on half of display
Okay, I'll go do that. If they all come back in the same range of >100 ohms, is it safe to say the issue is in the tcon?...Leave a comment:
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Re: Samsung UN46D6500VF - no display, odd lines and double image on half of display
Thanks for all of the helpful suggestions in this thread so far! I have that same $5 cheapo meter from HF, so I went back to try again.
I still wasn't able to get a reading on every one of the caps, but did pick up a reading of 170-180ohms on a few in each of the 3 tab bonding sections on the bad side, which seems to align with the readings on the 2-3 caps I checked on the good side as well. Is it necessary to check over every single one of the caps on the bad side...Leave a comment:
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Re: Samsung UN46D6500VF - no display, odd lines and double image on half of display
Just tried on the tcon, and couldn't get much of a reading either. Only one of the larger caps (labeled B1) came up with a reading of 0.2 ohms. None of the smaller units caused any movement. I tried two meters, but neither of them are very good, so maybe that's the issue?...Leave a comment:
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