This is a long story that has unfolded over about a month so please bear with me.
So I got the HK AVR 7000 broken off craigslist. It worked great in "surround off" mode, and was very weak in the right channel when it was in any surround mode, and was not doing surround at all. Optical input - same thing.
Now in 6ch input, it was perfect.
And headphones, never worked, it would flash HE on the display and back to what the display was showing, like say Tuner and station and breif burst of static in the headphones, and repeat
I isolated the issue to the dts board - and started to pull the receiver apart. Video board came off first., then the DTS board, and I should have tried to power it up and run speakers with the video board off but the dts in - I didn't do that. Anyway with the dts and video boards out, it powers up and tuner etc works as does switching inputs and surround modes etc, but no sound comes out. The safety relay clicks etc ... but no sound.
I thought that would not happen, I thought it will be making sound in 2 ch just fine. Anyway I guess sound has th go via the dts board no matter what, so I go on with its repair.
I find 3-4 swollen caps on the dts board, In the schematic these 4 caps are all 1000/6.3 and are all in 1 circuit. c65, c70, c73 and c170. They are in the +3v3a (c65) , +3v3d (c70 and c73), and +5vd (c170) section of the circuit. I suspect they are filtering of some kind, cos their other leg is to ground. So I suspect its losing some charge to ground and hence not supplying power where it needs to go.
I replace those and re assemble it, and the amp does not get past the standby stage.
So I pull the amp apart again, and I test it for power up with every component I disconnect. Nothing gets it to power up past stand by.
Then I find a 10000 mf 16v cap with the bulge on the main board. C520 as per the schematic. That now is on the filtering section of the 5vd, 3.3va, 3.3vd and 5vv lines.
So what is 5vd ? is it a way of identifying a 5v line ? its 5v but not the same as that other 5v over there ?
Then is 3v3d the same as 3.3vd ?
Now 1 swollen cap on these lines is a poor filter that has fried the rest of them down the line - I know that is possible. However is that enough to not let the amp power on ?
I am working on replacing that swollen cap, but would rather find all the problems right now and fix it instead of many more assemblies and disassemblies.
Thanks.
Srinath.
So I got the HK AVR 7000 broken off craigslist. It worked great in "surround off" mode, and was very weak in the right channel when it was in any surround mode, and was not doing surround at all. Optical input - same thing.
Now in 6ch input, it was perfect.
And headphones, never worked, it would flash HE on the display and back to what the display was showing, like say Tuner and station and breif burst of static in the headphones, and repeat
I isolated the issue to the dts board - and started to pull the receiver apart. Video board came off first., then the DTS board, and I should have tried to power it up and run speakers with the video board off but the dts in - I didn't do that. Anyway with the dts and video boards out, it powers up and tuner etc works as does switching inputs and surround modes etc, but no sound comes out. The safety relay clicks etc ... but no sound.
I thought that would not happen, I thought it will be making sound in 2 ch just fine. Anyway I guess sound has th go via the dts board no matter what, so I go on with its repair.
I find 3-4 swollen caps on the dts board, In the schematic these 4 caps are all 1000/6.3 and are all in 1 circuit. c65, c70, c73 and c170. They are in the +3v3a (c65) , +3v3d (c70 and c73), and +5vd (c170) section of the circuit. I suspect they are filtering of some kind, cos their other leg is to ground. So I suspect its losing some charge to ground and hence not supplying power where it needs to go.
I replace those and re assemble it, and the amp does not get past the standby stage.
So I pull the amp apart again, and I test it for power up with every component I disconnect. Nothing gets it to power up past stand by.
Then I find a 10000 mf 16v cap with the bulge on the main board. C520 as per the schematic. That now is on the filtering section of the 5vd, 3.3va, 3.3vd and 5vv lines.
So what is 5vd ? is it a way of identifying a 5v line ? its 5v but not the same as that other 5v over there ?
Then is 3v3d the same as 3.3vd ?
Now 1 swollen cap on these lines is a poor filter that has fried the rest of them down the line - I know that is possible. However is that enough to not let the amp power on ?
I am working on replacing that swollen cap, but would rather find all the problems right now and fix it instead of many more assemblies and disassemblies.
Thanks.
Srinath.
Hi Srinath,
I have the same problem as you, well.. as you had it, as the post is from 2012. So, I did the same on my AVR 7000, which was working, but sometimes had some "no sound" moments .. and I decided to disassembly the unit, go to the main board, where I did all the soldering again, and I found a 1000/10v swollen next to a 5V regulator, and 10.000/16v cap was swollen, but only the cover, as i've seen after moving it a little bit, anyway, testet if the receiver starts .. all was ok, but after putting all togheter (screws and frame) .. it won't turn on .. stays in stand-by .. i tried reset .. but with no succes. So, I was wondering, if you repaired yours .. what was the cause .. please help ! Thank you in advance ! Cheers.
I have the same problem as you, well.. as you had it, as the post is from 2012. So, I did the same on my AVR 7000, which was working, but sometimes had some "no sound" moments .. and I decided to disassembly the unit, go to the main board, where I did all the soldering again, and I found a 1000/10v swollen next to a 5V regulator, and 10.000/16v cap was swollen, but only the cover, as i've seen after moving it a little bit, anyway, testet if the receiver starts .. all was ok, but after putting all togheter (screws and frame) .. it won't turn on .. stays in stand-by .. i tried reset .. but with no succes. So, I was wondering, if you repaired yours .. what was the cause .. please help ! Thank you in advance ! Cheers.
Hey, sorry about the delayed response. The amp is in a box still dead.
I would at some point get to it, just may be years.
Thanks.
Srinath.
I would at some point get to it, just may be years.
Thanks.
Srinath.
Hey !
No probs, its never too late 🙂 Ok, so I found what was wrong with mine, dead main processor which is on the front pannel and i know how i killed it. During the dissassembly i touched the front ground to an final transistor and the cpu took some 63V from the transistor, now its getting hot, so i know its dead. I already sold mine for parts.
Good luck and all the best !
Roberto.
No probs, its never too late 🙂 Ok, so I found what was wrong with mine, dead main processor which is on the front pannel and i know how i killed it. During the dissassembly i touched the front ground to an final transistor and the cpu took some 63V from the transistor, now its getting hot, so i know its dead. I already sold mine for parts.
Good luck and all the best !
Roberto.
Hey Srinath,
i have repaired many AVR7000, so maybe I can help.
But I've to dig into the schematics first since it's been a while for your question.
The problem with a dead processor which Roberto describes is familiar.
When the amp is unpowered the large Capacitors remain charged, so when a loose cable touches a component in the poweramp there will be something fried.
Unplug the power to the poweramps with the 2 connectors pins cable ( red and white wires if i recall correctly ) before disassembly.
All the small electrolytic caps in the bottom PCB and the PCB above need to be replaced as they are dried out.
There is a small standbypowerPCB behind the frontpanel. The regulator there gets quite hot so check those electrolytic caps and solder connections as well.
I also remember that ground connections are made with the PCBs touching the back panel.
It's a good amp, worthwhile to refurbish.
Dick
i have repaired many AVR7000, so maybe I can help.
But I've to dig into the schematics first since it's been a while for your question.
The problem with a dead processor which Roberto describes is familiar.
When the amp is unpowered the large Capacitors remain charged, so when a loose cable touches a component in the poweramp there will be something fried.
Unplug the power to the poweramps with the 2 connectors pins cable ( red and white wires if i recall correctly ) before disassembly.
All the small electrolytic caps in the bottom PCB and the PCB above need to be replaced as they are dried out.
There is a small standbypowerPCB behind the frontpanel. The regulator there gets quite hot so check those electrolytic caps and solder connections as well.
I also remember that ground connections are made with the PCBs touching the back panel.
It's a good amp, worthwhile to refurbish.
Dick
I will try to get to in in the next few months. Thanks. I don't believe I killed mine - I hope I didn't.
However mine isn't powering up after I got to the fuses and checked them, the fuses @ the bottom of the power amp board on trhe bottom of the amp. Yea had to take the whole thing apart to even see it.
Thanks.
Srinath.
However mine isn't powering up after I got to the fuses and checked them, the fuses @ the bottom of the power amp board on trhe bottom of the amp. Yea had to take the whole thing apart to even see it.
Thanks.
Srinath.
- Status
- Not open for further replies.