Re: Onkyo SR-TX705 issue
Ok, I just confirmed it happens out of all speakers. I had the movie on pause for the last hour, went back to test it again (but left all 5 speakers connected). I hit play, and the ticks were happening rapid fire, going back and forth between the channels. I would say about 5-10 "ticks" in about 10 seconds, moving from speaker to speaker. It might've kept going, but my ears couldn't take much more so I hit pause again.
nerdbot
Senior Member
Last Activity: 06-28-2012, 07:20 PM
Joined: 04-24-2011
Location:
-
Onkyo SR-TX705 issue
Hi guys,
I was wondering if anyone might be able to shed some light on a problem I'm having with my Onkyo SR-TX705.
I have a 5.1 setup, and it seems when I listen to Dolby Digital 5.1 sources (Dolby Digital icon lit up on the receiver), I will randomly get a high pitched "tick" out of the side surround speakers. It really seems to be random - I've tried replaying the scenes where I hear the noise, and it doesn't happen again. It seems to happen at any frequency (happens during loud scenes, quiet scenes, bass heavy, high-pitched scenes, etc). Sometimes,... -
Re: Getting started with troubleshooting [Samsung 245BW]
Well, I think it's the actual LCD panel. I got a different logic board and a new LVDS cable, as well as new cables between the logic board and power board, and I get the same behavior: solid white screen.
Out of curiosity, I connected my wife's 24" monitor (a Dell) to the current limiter, and when I turn on the monitor the light bulb flashes while the LCD is dark, then the LCD tries to turn on while the light bulb dims, and it alternates back and forth like this. I also have the same result...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Ok, thanks for the info. I guess I'll look into RMA'ing the logic board or getting a new LVDS cable.Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Another observation I made was that on the replacement power board I received, the smaller connector between the power board and the logic board was bent (but does not seem broken) - I attached a picture and boxed it in blue.
This connector has the BL_EN and SOS pins, and I believe a DWM or DIM pin (I can check again when I get home). If this connector is actually damaged/broken on the power board, would that explain the constant white screen on my monitor?
If so, I'll probably try removing the...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
I double-checked the signal cable from the logic board to the LCD panel, and it appears to be properly seated, yet I still have a constant white screen. Could the cable be bad? Is there any way to test it (short of buying a new one)?Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
I got the replacement logic board in, wired it up, plugged it in to the current limiter, and left the inverter board unplugged. I tested a bunch of voltages to make sure things looked ok (S_B, 5.3V pins, 24V pins, voltage across the main capacitor, resistance on the various transistors with the power off, etc). Things looked ok, so I wired the rest of it up and connected the inverter board and a VGA cable.
The monitor turns on, and nothing popped, but the screen was bright white with no picture (but no longer...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Yeah, I hear you, but I figure I've already spent this much, may as well try one last time. I think the grand total I've spent so far on the 245BW, including the logic board I just ordered, is a little over $60, which is still a bit less than buying one brand new power board, and a lot less than buying a new 1920x1200 24"+ monitor. If this new logic board doesn't work, then I'll give up.
It's kind of crazy how much more expensive 1920x1200 monitors are over 1920x1080s. Must be a supply/demand...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Ah, ok. Let's hope so
Luckily, I was able to get a (supposedly) working logic board off of ebay for $20....
Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Well, I'm back. I ended up getting that used power board off of eBay for $20, and I replaced all the caps on it. I plugged it in to the logic board, connected the front bezel, and plugged everything into the current limiter power strip. I turned on the power switch on the power board, and the light bulb flashed momentarily then went dark. I then turned on the monitor and again, the light bulb flashed momentarily, then went dark, while the blue power LED stayed lit. From what I understand, this is correct behavior.
...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Yeah, I did notice that, though it still is a gamble. Maybe I'll wait until closer to the end of the auction. If I can get get it for closer to $20 (instead of the buy it now of $34), I might be inclined to try it (I did buy twice as many caps as I needed when I originally ordered the replacements caps for the 245BW...)
The monitors that are in there are often either dead KVM LCD panels or CRTs....Last edited by nerdbot; 05-21-2011, 08:04 PM.Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
I attached pictures of the red, green (both marked "EN210A 8222EN", and light blue ("FCQ1A04") transistor .
When I pulled out the red transistor and measured it again, I got the following readings (counting pins from left to right using the attached pictures):
Black Pin 1, Red Pin 2 - Out of range
Black Pin 1, Red Pin 3 - Out of range
Black Pin 2, Red Pin 3 - 140.8 Ohms
Since the little icons on the transistor looked like diode symbols, I also tried:...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
I guess anything's possible... I recall saying earlier how I was surprised I didn't screw up something bigger sooner
Could it be that when I tried those first two resistors (before fixing the QM802/803 mosfets) that it caused damage to the other 4 transistors? When the resistors blew, I didn't turn off the power immediately, but maybe 15-20 seconds later.
I'll desolder one of them in the morning. If it does turn out that they are shorted, I believe Th3_uN1Qu3 said they were kinda hard to...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Red - EN210A 8222EN
Green - EN210A 8222EN
Couldn't find a datasheet for these 2
Light blue - N 8A FCQ10A04 S255K
Magenta - SIK (i think) 8008HFE
I tested them using the same method I used for the other MOSFETs, though I think the "light blue" transistor is a Schottky Barrier Diode, so I'm not sure if that's the proper way to test it.
Red transistor -
Black Pin 1, Red Pin 2 - 19.7 ohms
Black Pin...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Ok, now this is weird. I searched other threads for "953-18" to see if anyone else had measurements I could compare against (which I did find, and I guess my readings are normal). I then checked the voltage across the main capacitor, that previously measured 160V. It now reads 384V!
Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
The red circle is IC705, and the part number is AnaChip 1501-33. Here is the data sheet:
[url]http://www.alldatasheet.com/datasheet-pdf/pdf/87870/ANACHIP/AP1501.html[/url]
The measurements for the 1501-33 are:
Pin 1: 5.18V
Pin 2: 3.30V
Pin 3: 0V
Pin 4: 3.23V
Pin 5: 0V
From what I can understand from the datasheet, it seems that Pins 1 through 4 have the correct values, but I'm not sure about Pin 5?
The part number on IC703 is "J412...Last edited by nerdbot; 05-20-2011, 08:00 PM.Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Even with the inverter board disconnected, I get 0V on the "24V" pins. I traced those pins back to the "+5.3V" pins on the connector on the left side of the board (using the continuity feature), and those +5.3V pins also measure 0V. I made sure the monitor was "on" and not in "standby" when measuring the voltages.
I don't know if it's relevant, but I also took measurements on the smaller cable on the left hand side, above the cable that has the S_B pin....Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Well, not fixed yet, but more progress...
I put in the new MOSFETs with a little silicone thermal paste (not the Arctic Silver, just to be safe) and put a new 1W 0.22 ohm resistor in RM801. I was also able to wire up that light bulb current limiter using an extension cord, so I was able to use that to make sure there wasn't a short somewhere else that would blow the resistor or the new MOSFETs.
I then connected the logic board to the power board, and now I get a steady 5.2V on the S_B pin,...Leave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Thanks Th3_uN1Qu3, I found some links for how to build a "light bulb current limiter" which, from the descriptions, sounds exactly like what you described. I think this one may be the easiest for me to wire up myself:
[url]http://www.io.com/~beckerdo/guitars/20100509CurrentLimiter/index.html[/url]Re: Getting started with troubleshoo...sounds exactlyLeave a comment:
-
Re: Getting started with troubleshooting [Samsung 245BW]
Ah ok, thanks for clarifying!
To do the test with the light bulb as you mentioned, I'm guessing I'd need to get a light bulb socket like the one I attached, and some alligator clips to clip to the metal prongs holding the fuse? Also, which fuse would I connect it to since there are 2 fuses?...Leave a comment:
No activity results to display
Leave a comment: