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Denon AVR-1912 E2/EA

What you really need is assistance from someone with the appropriate fault location skills but ON-SITE.
Great idea. Why not invite Michael up one weekend and perhaps can lend a hand? :)

Michael seems to be making progress in my opinion, but yes, some assistance isn't a bad idea.
 
Michael, I have a feeling this missing ground isn't on the boards themselves but a result of how they interconnect (plug in) with the front/side boards.
I think I'd temporarily jumper the Agnds together to see if it restores power to your ICs. At that point you can evaluate what's working and how you should proceed.
 
Whilst that might be a reasonable response Michael is over 10 hours drive from me (minimum)!

Yikes! What're'ya comming from the outer Hebrides? I can drive that distance in half that time. I realize the mountains can slow you down, but wow.

Btw, I was only kidding and didn't mean to put you on the spot.
 
I must confess that I 'lost interest' in this repair some time ago - after nearly 600 replies and 30 pages of responses I'd respectfully suggest that the repair is beyond your capabilities as far as getting feedback from a forum is concerned.

What you really need is assistance from someone with the appropriate fault location skills but ON-SITE.

Somehow I doubt that the fault(s) is/are extensive as 30 pages of replies make them out to be and that starting from square-one would be a good thing.

I'd hate to think that what you've been doing has actually introduced problems rather than curing them!

Just a thought......
Well, Kelly's Eye . . . . what can I say?? I don't believe your opinion was sought. Michael Studio1 UK 21:49BST 06-06-2018
 
Btw, I was only kidding and didn't mean to put you on the spot.
Not a problem! If anyone was local to me I'd be only too happy to assist.

I can drive from my place to Bristol (where my son lives) in 9 hours but it takes nearly three hours just to get to the main motorway from my place - it's rather off the beaten track...

I don't believe your opinion was sought.
Yep, I (expected) deserve that! Still, it is just 'my' opinion and it was not meant as an insult, only as practical advice for which, as the above states, I would happily oblige had you been more local to me.

I have to admire your tenacity and determination though!
 
I don't believe your opinion was sought.

Michael Studio1 said:
Thanks for your reply, Kelly's Eye. Indeed you have given me hope - and a good starting point.
BTW - it was..... when you first posted and seemed happy enough to take it.......

If you were happy to accept my advice to begin with I see nothing wrong with further advancing my opinion given the change in situation - advice given in good faith and no malice aforethought.....
 
Michael, I have a feeling this missing ground isn't on the boards themselves but a result of how they interconnect (plug in) with the front/side boards.
I think I'd temporarily jumper the Agnds together to see if it restores power to your ICs. At that point you can evaluate what's working and how you should proceed.
Thanks, John. Another excellent suggestion. The 'stack' on the bench has the SIDE_B'D and FRONT_B'D so I am able to evaluate the GND situation (I think) But today I did actually complete making the two Keith Monks : Standard mic-boom adaptors. They look a treat. Now I can concentrate on the AVR. The observation from whoever 10Hrs drive away is, is rather counter-productive. I'm sorry he lost interest - but this is an extremely complex and interesting repair - and very close to completion, I feel. Michael Studio1. UK
 
Not a problem! If anyone was local to me I'd be only too happy to assist.

I can drive from my place to Bristol (where my son lives) in 9 hours but it takes nearly three hours just to get to the main motorway from my place - it's rather off the beaten track...


Yep, I (expected) deserve that! Still, it is just 'my' opinion and it was not meant as an insult, only as practical advice for which, as the above states, I would happily oblige had you been more local to me.

I have to admire your tenacity and determination though!
Thank you Kelly's Eye. I didn't think there was an upper limit in 'Pages' or 'Time' one could take in resolving a problem - and I must confess your observation was a bit upsetting. However, I am determined NOT to get Denon involved when, with help such as I am getting on this thread, I can 'do-it-myself' and get that satisfaction. A little while ago I changed all the transistors in my AKAI 635-D reel-to-reel NAB huge, heavy stereo Tape recorder using inspired help on line. Maybe this'll get into the Guinness Book of Records in some capacity or other - take your pick! Michael Studio1 08:29BST 07-06-18
 
I have to admire your tenacity and determination though!
I wouldn't suggest you STOP what you're doing - as a semi-retired person myself I charge £25 to fix electrics/electronics regardless of how long it takes me as 'time' is something I have plenty of (within the confines of the grim reaper that is :D).

I was speaking in respect to (potential) frustration - not only to yourself but to those contributing to the thread as you may eventually find yourself to be the only contributor! Looking through the thread I can see this happening now.....

But, specifically, when a thread runs past a given number of pages there will be few people who have the time and/or inclination to trawl through dozens of pages to get a grasp on the situation enough to be able to offer an input - this is why I said I'd 'lost interest'.

It may be helpful (to yourself and others) to break the problem down and have separate threads for each - linking (by posting clickable links) - where it is necessary to join up details.

Even now, as much as I tend to drop in on the thread to see where it's going I (seriously) haven't got the will to review it ALL so assistance, where I might be able to offer it, is sadly lacking.

Might I then suggest you 'start again' with thread(s) titled

DENON AVR - DISASSEMBLING;
DENON AVR - PSU;
DENON AVR - DIGITAL;
DENON AVR - ANALOG etc etc.....

and tackle the various issues individually where you're more likely to get (and keep) interested parties?

I'm only trying to help!
 
I wouldn't suggest you STOP what you're doing - as a semi-retired person myself I charge £25 to fix electrics/electronics regardless of how long it takes me as 'time' is something I have plenty of (within the confines of the grim reaper that is :D).

I was speaking in respect to (potential) frustration - not only to yourself but to those contributing to the thread as you may eventually find yourself to be the only contributor! Looking through the thread I can see this happening now.....

But, specifically, when a thread runs past a given number of pages there will be few people who have the time and/or inclination to trawl through dozens of pages to get a grasp on the situation enough to be able to offer an input - this is why I said I'd 'lost interest'.

It may be helpful (to yourself and others) to break the problem down and have separate threads for each - linking (by posting clickable links) - where it is necessary to join up details.

Even now, as much as I tend to drop in on the thread to see where it's going I (seriously) haven't got the will to review it ALL so assistance, where I might be able to offer it, is sadly lacking.

Might I then suggest you 'start again' with thread(s) titled

DENON AVR - DISASSEMBLING;
DENON AVR - PSU;
DENON AVR - DIGITAL;
DENON AVR - ANALOG etc etc.....

and tackle the various issues individually where you're more likely to get (and keep) interested parties?

I'm only trying to help!


Hello Kelly's Eye - right now I seem to have just "tha fios agaibh" following me. That's a good suggestion. However I need to pick the most likely 'thread' and the subject is (Ha! Ha!) "Losing GND". Which is so. I am trying to trace the AGND downstream from Page111/D10 (~) pin4 to which I have a DVM probe connected. I have assembled a 'stack' of four PCB's out of the Denon Chassis in order to get at all relevant pins with the other probe. The PCB's are: HDMI, AUDIO_VIDEO, SIDE CONNECTOR and FRONT CONNECTOR. This means of tracing is working well. To assist I am using the AVI-1912E2/EA Service manual and its search tool CTRL+F. This gets me to all the physical board layouts on both sides 'FOIL' and 'COMPONENT'. Asking the search tool to find components is simplicity itself - and, of course, the image may readily be magnified to view the resultant 'Blued-out' component. So far this morning my search of AGND path from CN13 pin4 has led me to six grouped resistors on page114/K5. The next obvious test point is at the 7CH_AMP connection on page114/D3-4 CN401 pins - any even numbered. But there is no continuity to the AGND there. Why? Good question. I retired from Glyndebourne Opera in 2006 after 26 years tuning Harpsichords and Pianos for the LPO. SO I too have time on my hands. One significant historical electronic breakthrough I do remember was when, in Year2 (Senior) I was told of the New Electronic Invention: the Transverse Resistance. "There goes my PM2" I thought - rather like the telephone saying "You too can be replaced by a single contact relay" Ha-Ha! So which thread more suitably fits my on-going quest I wonder? Michael Studio1 UK 11:03BST 06-06-2018
 
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Question: When, as on Page114/L5, GND Ccts. cross each other - are they necessarily connected? If so I cannot see the reason for that clutch of 6 resistors at ref.L5, (R's 831,832,836,837,839,840) being wired up that way. Anyone free to interpret this way of drawing up a Cct.? Michael Studio1 UK 12:24BST
 
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No, they cross but are not connected.
When you see a round dot on a crossing line they are connected.
Yes, John, Bushtech has just said the same thing. I simply couldn't see the blobs (or lack of blobs) where they cross - until I enlarged out of all proportion. I'll (as I also said) be glad when my other eye has been operated on for Cataracts. Even so I have run into a dead end in my quest for AGND and find so many components with the term 'OPEN' beside them. They are physically there but there's no 'beep' from the dvm to show it . . . . unless . . . I've just found the Eureka moment? Now Harald has just asked why I started a new thread. He's right to do so. Have I made a tactical error? Michael Studio1 UK 18:52BST 06-06-2108
 
As I said (three times now) just jumper a good Agnd point to where your Agnd is not available (CN13a)
In other words, solder a wire to a convenient point of "good" Agnd and the other end can go to CN13A (Dead Agnd) or a point near it that connects to it.
You seem to be going all around hells half acre (or should I say hectare) looking for it, when the missing link should be near or ON CN13A.
 
As I said (three times now) just jumper a good Agnd point to where your Agnd is not available (CN13a)
In other words, solder a wire to a convenient point of "good" Agnd and the other end can go to CN13A (Dead Agnd) or a point near it that connects to it.
You seem to be going all around hells half acre (or should I say hectare) looking for it, when the missing link should be near or ON CN13A.
Somewhere, John, I said: Have you ever driven into the town you were looking for only, because you were unfamiliar with the area - and driven out again? Then the next finger post tells you your destination is behind you (a Pantomime Joke there, I think) so you turn around and get thoroughly lost because the town is unidentified. I have. Been there, done that. Still waiting for the 'T' shirt though! That's a bit like this GND hunt. So what constitutes a "good" Agnd? Presumably anywhere (hopefully close) near the CN13A area. Yes, John, Good thinking. I know you've already suggested this a thousand times but I'm just beginning to appreciate it. Will do . . . . . Then I can put it together again and find out why there's nothing arriving at the Speaker Terminals . . . or will there be? . . . Michael Studio1 UK 19:52 The year after the Festival of Britain. That's remembered in the Festival Hall on the South Bank of the Thames. Michael.
 
Somewhere, John, I said: Have you ever driven into the town you were looking for only, because you were unfamiliar with the area - and driven out again?
Maybe you said it in a different thread?o_O

Even when I get lost driving, There's a point where I know where I am, and another where I know I'm lost.
The point Agnd is lost is one side of CN13A and I believe you have Agnd pretty much anywhere else, right?
For that matter, you could jumper from dead Agnd on CN13A to chassis ground which is the same as Agnd.
 
Maybe you said it in a different thread?o_O

Even when I get lost driving, There's a point where I know where I am, and another where I know I'm lost.
The point Agnd is lost is one side of CN13A and I believe you have Agnd pretty much anywhere else, right?
For that matter, you could jumper from dead Agnd on CN13A to chassis ground which is the same as Agnd.
Yes, John, and thanks for this confirmation - my plan is to do that today (and watch the sparks fly)
 
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