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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Fri Feb 03, 2012 8:39 pm Post subject: |
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I learned that when I pulled the CN96 pin1 that it still blew F901, per your request. Another thing I learned was that it still blew when several boards were not plugged in. I was able to turn it off and on several times before it blew the fuse, making me think it could be heat related.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Fri Feb 03, 2012 9:12 pm Post subject: |
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Remove or cut the wire from BN92 pin 5 and try again.
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Sat Feb 04, 2012 5:04 am Post subject: |
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Saw the same senario with respect the flashing standby. Powered it on, heard relay trip, no display of any type, then relay dropped and back to standby. Did the power on several times, same senario. However, did not blow any fuses.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Sat Feb 04, 2012 3:12 pm Post subject: |
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Good. Now with those wires still disconnected I need you to test the input and output voltages of ic91 and ic92. If you have +8v on both inputs and +5v on both outputs then reconnect the first wire you disconnected, CN96, pin 1 and recheck those voltages on the ic's. Let me know what you get.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Sun Feb 05, 2012 4:49 pm Post subject: |
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Is there a post missing here jmdigges?
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Mon Feb 06, 2012 1:34 am Post subject: |
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Sorry for the delay, I've been at a all weekend wrestling tournament watching my grand kids. Those things are too long and drawn out.
I made a post and then saw that I had made a mistake so I deleted it and it's taken me a while to get back to redo it. Here's what happened... ran test per your request, but first had to replace bad fuse f901. Then did test with with following results.
Without CN96 pin 1 connected: (IC92 Input +7.89v, Output +5.04v), (IC91 Input +7.93v, Output +4.95v)
With CN96 pin 1 connected: (IC92 Input +7.83v, Output +5.04v), (IC91 Input +7.81v, Output +4.95v)
Thought this looked pretty good, and went back recheck the numbers. so I looked everything over and discovered I had left CN93 unplugged. So I plugged it in retested everything and got these numbers.
Without CN96 pin 1 connected: (IC92 Input +2.08v, Output +1.88v), (IC91 Input +2.23v, Output +1.90v)
With CN96 pin 1 connected: (IC92 Input +2.23v, Output +1.80v), (IC91 Input +2.09v, Output +1.90v)
These values are the highs that I saw, they were all ranging quite a bid because it was automatically shutting down. I got one reading per power on.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 1:52 am Post subject: |
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Interesting. Ok, disconnect that CN93 again. Now reconnect BN92, pin 5. So now everything is reconnected except for CN93. Now check those voltages again at ic91 and ic92.
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Mon Feb 06, 2012 2:24 am Post subject: |
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I must be really getting tired I miss keyed the CN number on the last post it was BN94 that I had left disconnected. Anyway unplugged it again and everything tests good. Vrey close to the previous numbers.
With CN96 pin 1 and BN92 pin 5 connected:
(IC92 Input +7.90v, Output +5.05v), (IC91 Input +7.93v, Output +4.95v)
Another point of interest, the standby is not flashing in the off position, it is solid red. When powered on it is out completely and the blue dial diodes are on.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 4:01 pm Post subject: |
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The standby being solid red and then going out when powered on is normal. The blue lights coming on is also normal but I'm surprised that the display is not coming on also. There may be more then 1 problem. But we will do 1 at a time and see.
I'm glad you keep catching your mistakes because we could be off in a completely wrong direction.
So it looks like we are heading off to the Video PWB, the one with the video ins and outs. On that board locate CN31 and CN40 and disconnect then.
Now go back to the regulator board and reconnect BN94, power it up and test your voltage at ic91 again. Let me know what you get.
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Mon Feb 06, 2012 4:42 pm Post subject: |
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Great shot:
CN91 +7.35v, +4.95v
But, more important screen says 7.1 input, scrolls vol and misc other displays. Select buttons all seem to be working.
Where do we go from here!
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 4:46 pm Post subject: |
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Ok, good. Now plug CN40 back in but leave CN31 disconnected and test your voltage again.
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Mon Feb 06, 2012 4:51 pm Post subject: |
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CN91 +7.18v, +4.95v
Still have all displays.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 4:59 pm Post subject: |
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Looks like the problem is on the HDMI board.
The receiver may even work leaving CN31 disconnected if you want to test it out.
If you want to continue and test out the HDMI board thats fine too. I would probably test for any DC on the speakers outputs and if none then connect some speakers and try it out first. Let me know what you want to do.
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Mon Feb 06, 2012 5:26 pm Post subject: |
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What would be the best case senario if you didn't have HDMI available? I can't see it being of much value. The board looks pretty tight to me - extremely small resisters and impossible to replace IC's (for me). I could do the caps and simple IC's. Would it be possible to get partial function? Maybe only one port is bad, could it be isolated? And then what would a board cost? Just trying to assess where to go. How difficult from here to isolate the problem?
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 5:35 pm Post subject: |
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We can continue to trouble shoot it and see if it came to a point where you are unable to go further. It may be easier then you think. But I would at least like to verify the rest of the receiver works before going further with the HDMI board.
What good is a repaired HDMI board if the receiver doesn't work? 
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Mon Feb 06, 2012 6:01 pm Post subject: |
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Good point. I pulled that card and am looking at it. I am not convinced that it didn't get maybe a little touch of water. Three reasons: 1. It sticks out on top of other boards other than a very short input board which is above it. 2. It looks like a light film of calcium or other white oxidation is on it. Like I've seen in cell phones having been dropped in water. 3. I see something I believe is a burn spot right at the end of CN6x , next CN61 on B side of board. the 'X' is not visible. It also has a wire coming from the end of that port where to me it looks like it may have been fixed before due to a board film layer being burned. It wraps to the other side and is soldered into the base of a cap and another point, probably ground. Crazy. I would like to talk to the guy that my grandson got the unit from. Anyway, I am ready to continue. I can email a pic.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 6:06 pm Post subject: |
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Are you going to test the receiver first or do you just want to continue finding the problem on this board?
If you can post a picture here I would mind seeing it.
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jmdigges
Joined: 31 Jan 2012
Posts: 43
Location: tulsa, Ok
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| Posted: Mon Feb 06, 2012 7:06 pm Post subject: |
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I emailed a couple of pics to forum-support, don't know how good they will be. I would like to see if we can locate the problem on this board. Maybe we would only lose part of the HMDI or maybe like you said even fix it.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 7:15 pm Post subject: |
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Send them to my email. They probably wont go anywhere sending them to the forum.
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macgyver655
Joined: 22 Aug 2007
Posts: 8508
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| Posted: Mon Feb 06, 2012 8:30 pm Post subject: |
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I'm going to give you a list of parts to test. No power is needed so you can remove the board. They are mostly 3 leg regulators and a couple diodes. I don't need you to test them for accuracy but just look for anything close to a short when testing among the legs. Your DMM will be on diode scale. Again, just real quick across the legs looking for a close to short condition.
Here's the list.
ic89, ic90, ic92, ic93, ic94, ic95, ic96, ic97, ic98, ic99.
D901 and D902.
All these are on the HDMI board.
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