|
|
Post by 24century on Feb 5, 2018 11:17:21 GMT -5
Do you get the same symptoms in Direct mode? Yes, it happens on all sources and all modes on main zone |
|
|
|
Post by mastertech on Feb 5, 2018 11:28:31 GMT -5
That is interesting. So if you are using just an analog input and put the receiver in "PURE DIRECT" mode it still cuts out?
|
|
|
|
Post by 24century on Feb 5, 2018 20:43:49 GMT -5
correct and it is odd
|
|
|
|
Post by mastertech on Feb 7, 2018 16:00:51 GMT -5
If you are willing to do some experimenting I could look for some suggestions. It would probably involve soldering on some fly wires to connect to your DMM to monitor when it cuts out.
|
|
|
|
Post by 24century on Feb 7, 2018 19:57:03 GMT -5
If you are willing to do some experimenting I could look for some suggestions. It would probably involve soldering on some fly wires to connect to your DMM to monitor when it cuts out. I m ok with jumping wires, pls advise |
|
|
|
Post by 24century on Feb 7, 2018 20:03:47 GMT -5
If you are willing to do some experimenting I could look for some suggestions. It would probably involve soldering on some fly wires to connect to your DMM to monitor when it cuts out. I m ok with jumping wires, pls advise And I understand it is under my own risk, no guarantee, just for gain experience |
|
|
|
Post by mastertech on Feb 7, 2018 20:20:10 GMT -5
Ok. 1 more question before we go that route. When you were testing with an analog input did you try a setting of "Pure Direct" or "Straight" mode? Or both?
Try using Audio 1 input and try both "Pure Direct" and then try "Straight" and see if it still cuts out on both.
|
|
|
|
Post by 24century on Feb 8, 2018 20:40:14 GMT -5
Double checked by 2 different time, with AV1 source and FM
"Straight", cutting off a lot of more often, start for 30-40 sec cut off and resume after 5-8 sec last 3 sec then cut off again, it may last a little longer after resuming but it will do again, that is Straight, stereo with woofer
"Pure Direct", a different type of cutting off, 1st round it last one minuet resume after 10 sec.
Every time it does last longer then "Straight", you can hear the relay click when it happen
Yamaha put front display off during "Pure Direct" therefore can't tell the status, Pure Direct = stereo without LPF
Zone 2 is absolutely perfect without any problem
|
|
|
|
Post by mastertech on Feb 8, 2018 21:24:08 GMT -5
You are going to have to go to page 133 of the service manual. You will see the DIR and DSP chips. There are around 7 or so voltages that feed those ic's. You will have to find the best place to connect to so you can monitor the voltages when the unit cuts out and see if any of them change. Make sure you check them all, even if you find 1 or to go bad when cut out because we would need to know how many voltages are being affected to determine if it is a line voltage problem or an ic problem. Let me know when you are finished testing.
|
|
|
|
Post by 24century on Feb 18, 2018 19:18:27 GMT -5
Finally get some time and space to do the 2nd round disassembly & test.
IC929, CMOS power regulator appear to be reliable
IC930, 3.3V, reliable weather sound drop or not
IC931, 5V, reliable weather sound drop or not
931 input voltage change in its own rhythm
Q9201 is on the reverse side of PCB, can't locate IC932
that's the progress so far
|
|
|
|
Post by 24century on Feb 18, 2018 21:01:42 GMT -5
Tested onboard caps, C9252/9253/9212 (10uF/16V) appear to be unstable, can those be causing the problem like this by experience?
|
|
|
|
Post by 24century on Feb 19, 2018 14:54:30 GMT -5
Tested this morning again around those 3 caps, voltage cross each cap change from 2.29V (playing mode) to 2.39V (audio dropped) Took those off all three of them are perfectly good in 10uF, turn unit on without 3 caps, problem stays same. soldered those back, no progress made, looks like the power who feed this part is unstable Ref: service manuel P.133 left mid section  |
|
|
|
Post by mastertech on Feb 19, 2018 19:48:19 GMT -5
I just don't think 1 tenth of a volt indicates anything. But at least you are putting in some effort.  |
|
