The symptom you are describing is indicative of cold solder joints. If you
have proper soldering tools, and experience,you should be able to complete
the repair, if not, i'd advise that you take you take your receiver to a
repair shop, where you can at least get an estimate. Which most shops offer
for free.

Dan
"Bernhard" wrote in message
...
My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.

I already opened the case and tried to force a shutdown by
knocking on all boards, connectors, switches and everything
inside. I could not find any connection with my actions and
the intermittend shutdowns.

Before I buy the service manual and disassemble the unit,
I would like to ask, if anyone else had this error and could
help me.

Thank you very much.

Bernhard (backs*mailandnews.com)

My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.

I already opened the case and tried to force a shutdown by
knocking on all boards, connectors, switches and everything
inside. I could not find any connection with my actions and
the intermittend shutdowns.

Before I buy the service manual and disassemble the unit,
I would like to ask, if anyone else had this error and could
help me.

Thank you very much.

Bernhard (backs*mailandnews.com)

"Sofie" wrote in message
...
snipped:
"Bernhard" wrote in message
My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.
Bernhard

I'd first check to be sure that you don't have any shorted strands on
speaker wires,

---------------------------------------------
Bernhard:
Regarding the symptoms you described, "buying the service manual and
disassembling the unit" is not going to fix the problem nor will the
service
manual offer you specific suggestions and procedures for repair.... the
service manual is only most useful to knowledgeable and experienced
technicians who probably can fix the equipment without the manual..
What you described is most likely, as the previous reply post by "Dan"
correctly stated, caused by faulty solder connections and/or possibly
intermittent connectors. This is a routine repair at most service shops
that most likely does NOT require the hard to get and expensive service
manual.

Service manuals for Yamaha receivers are easy to get (from Yamaha) and
relatively inexpensive at $18 retail, $12 dealer cost. It can be useless to
someone who is inexperienced in these units, as stated previsously and
perhaps not needed for this repair.


As "Dan" suggested, at the very least take it to a service shop for a
repair
cost estimate..... so you can make an intelligent repair decision with
facts
instead of guesses. If you take it to the shop AFTER aborted or failed
home repair attempts, or after continuing to operate the unit with this
problem until it gets worse to the point it won't work at all, the repair
shop price will certainly be much higher.

Good advice.

Leonard Caillouet

snipped:
"Bernhard" wrote in message
My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.
Bernhard
---------------------------------------------


Bernhard:
Regarding the symptoms you described, "buying the service manual and
disassembling the unit" is not going to fix the problem nor will the service
manual offer you specific suggestions and procedures for repair.... the
service manual is only most useful to knowledgeable and experienced
technicians who probably can fix the equipment without the manual..
What you described is most likely, as the previous reply post by "Dan"
correctly stated, caused by faulty solder connections and/or possibly
intermittent connectors. This is a routine repair at most service shops
that most likely does NOT require the hard to get and expensive service
manual.
As "Dan" suggested, at the very least take it to a service shop for a repair
cost estimate..... so you can make an intelligent repair decision with facts
instead of guesses. If you take it to the shop AFTER aborted or failed
home repair attempts, or after continuing to operate the unit with this
problem until it gets worse to the point it won't work at all, the repair
shop price will certainly be much higher.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
-----------------------------

Thanks Dan.
Good idea. I'm an experienced electronics hobbyist and have the proper
soldering tools and I should have known that... I will disassemble the
board where the power switch together with the microcontroller is
located and inspect it. Maybe there is a cold solder joint that worked
for the first 3 years and is now getting worse by the permanent
mechanical
stress of pushing the power switch.
If anyone else has experienced the same error, please post your
solution.

Bernhard (backs*mailandnews.com)

Dan wrote:

The symptom you are describing is indicative of cold solder joints. If you
have proper soldering tools, and experience,you should be able to complete
the repair, if not, i'd advise that you take you take your receiver to a
repair shop, where you can at least get an estimate. Which most shops offer
for free.

Dan
"Bernhard" wrote in message
...
My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.

I already opened the case and tried to force a shutdown by
knocking on all boards, connectors, switches and everything
inside. I could not find any connection with my actions and
the intermittend shutdowns.

Before I buy the service manual and disassemble the unit,
I would like to ask, if anyone else had this error and could
help me.

Thank you very much.

Bernhard (backs*mailandnews.com)

Daniel,
Thanks for your suggestions.
I know what a service manual contains and I'm experienced enough to
not trying to repair my receiver to death. I mentioned to buy the
service manual because the device is filled up with so much boards
that it was difficult to tell their exact function (and after some
years I usually need the manual for some other repairs).

Another point is the qualification of service personnel in repair shops
here in Germany. Almost all of them work on a "pay-per-module" base:
Let's first exchange the module or PCB that makes up the control panel
with the power switch (ups.. thats about $100.-) next let's try the
power supply (another $130.-) and so on. The price for a repair cost
estimate is around $50.- if you don't actually let the device be
repaired in that shop. And my personal experience is that most repair
cases have been really small things like a burned diode or a dead
electrolytic capacitor and could be fixed for a buck or so (not taking
into account the time I need to locate the error, but I don't have to
pay for it).

I think, Dan and you are right with your guess and I will try to find
the faulty solder joint.

Bernhard (backs*mailandnews.com)

Sofie wrote:

snipped:
"Bernhard" wrote in message
My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.
Bernhard
---------------------------------------------

Bernhard:
Regarding the symptoms you described, "buying the service manual and
disassembling the unit" is not going to fix the problem nor will the service
manual offer you specific suggestions and procedures for repair.... the
service manual is only most useful to knowledgeable and experienced
technicians who probably can fix the equipment without the manual..
What you described is most likely, as the previous reply post by "Dan"
correctly stated, caused by faulty solder connections and/or possibly
intermittent connectors. This is a routine repair at most service shops
that most likely does NOT require the hard to get and expensive service
manual.
As "Dan" suggested, at the very least take it to a service shop for a repair
cost estimate..... so you can make an intelligent repair decision with facts
instead of guesses. If you take it to the shop AFTER aborted or failed
home repair attempts, or after continuing to operate the unit with this
problem until it gets worse to the point it won't work at all, the repair
shop price will certainly be much higher.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
-----------------------------

Work on these all the time possible loose ground screws on input jack assy or
broken ground connection
in same area. Also bad sorder connections on sram chip near main processor {very
small connections
must be very good at soldering!!

Steve
N.J.

Bernhard wrote:

Daniel,
Thanks for your suggestions.
I know what a service manual contains and I'm experienced enough to
not trying to repair my receiver to death. I mentioned to buy the
service manual because the device is filled up with so much boards
that it was difficult to tell their exact function (and after some
years I usually need the manual for some other repairs).

Another point is the qualification of service personnel in repair shops
here in Germany. Almost all of them work on a "pay-per-module" base:
Let's first exchange the module or PCB that makes up the control panel
with the power switch (ups.. thats about $100.-) next let's try the
power supply (another $130.-) and so on. The price for a repair cost
estimate is around $50.- if you don't actually let the device be
repaired in that shop. And my personal experience is that most repair
cases have been really small things like a burned diode or a dead
electrolytic capacitor and could be fixed for a buck or so (not taking
into account the time I need to locate the error, but I don't have to
pay for it).

I think, Dan and you are right with your guess and I will try to find
the faulty solder joint.

Bernhard (backs*mailandnews.com)

Sofie wrote:

snipped:
"Bernhard" wrote in message
My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.
Bernhard
---------------------------------------------

Bernhard:
Regarding the symptoms you described, "buying the service manual and
disassembling the unit" is not going to fix the problem nor will the service
manual offer you specific suggestions and procedures for repair.... the
service manual is only most useful to knowledgeable and experienced
technicians who probably can fix the equipment without the manual..
What you described is most likely, as the previous reply post by "Dan"
correctly stated, caused by faulty solder connections and/or possibly
intermittent connectors. This is a routine repair at most service shops
that most likely does NOT require the hard to get and expensive service
manual.
As "Dan" suggested, at the very least take it to a service shop for a repair
cost estimate..... so you can make an intelligent repair decision with facts
instead of guesses. If you take it to the shop AFTER aborted or failed
home repair attempts, or after continuing to operate the unit with this
problem until it gets worse to the point it won't work at all, the repair
shop price will certainly be much higher.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
-----------------------------

I am less inclined toward the solder connections, since Yamaha's are a bit
less prone to this. If it were solder connections, I would look closely at
the solder at the bias transistors - this is the only place I've seen this
on later Yamaha's.

I'm leaning much more towards the speaker wiring, a loose strand crossing
over etc.

Mark Z.


"Dan" wrote in message
...
The symptom you are describing is indicative of cold solder joints. If
you
have proper soldering tools, and experience,you should be able to complete
the repair, if not, i'd advise that you take you take your receiver to a
repair shop, where you can at least get an estimate. Which most shops
offer
for free.

Dan
"Bernhard" wrote in message
...
My Yamaha RX-V795 receiver shows a strange behaviour.
After switching the device on, it shuts down immediately
or after some seconds or after a longer period of time,
sometimes after 1 or 2 hours.

This often happens when I inadvertently bump against the
rack on which the receiver is located - but it also happens
when absolutely no mechanical vibrations are present.

I already opened the case and tried to force a shutdown by
knocking on all boards, connectors, switches and everything
inside. I could not find any connection with my actions and
the intermittend shutdowns.

Before I buy the service manual and disassemble the unit,
I would like to ask, if anyone else had this error and could
help me.

Thank you very much.

Bernhard (backs*mailandnews.com)