I have an old Yamaha CR-820 receiver/amplifier that no longer has any sound
output. The meters still show signal strenght when a tune across the AM/FM
bands but I get no audio from the speakers or the phone jack. No hiss. hum,
carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can obtain a
schematic or service manual?

"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has any
sound output. The meters still show signal strenght when a tune across the
AM/FM bands but I get no audio from the speakers or the phone jack. No
hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can obtain a
schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown ) fuse,
then it's most likely that the speaker protection circuit is operating
because of a blown output stage. I've a vague recollection that this one
uses an output hybrid ( big black "IC" bolted to the heatsink with type
STK-xxx ) and if so, it is likely that this is your problem. Some of these
can be very expensive, and many of the older ones are now obsolete and hard
to obtain. If it is one of the models that uses discrete output stages, then
you might struggle to get to the bottom of its problems, particularly
without a set of schematics, which again, might be difficult to find for an
item this old.

Arfa

Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for newbies -
there's fusible resistors inside asbestos tubing which go bad, usually
without any visible clue, and the layout is hardly service-friendly.

Mark Z.

"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for newbies -
there's fusible resistors inside asbestos tubing which go bad, usually
without any visible clue, and the layout is hardly service-friendly.

Mark Z.


Thanks for the information all.

Yes there are 4 heat sinked bipolar transsitors. They cost about $10 each.
They get warm to the touch.

I bought a service manual for $15 bucks.

I will see what I can find out. This was a friend's unit.

I wil check out those fusible resistors.

"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for newbies -
there's fusible resistors inside asbestos tubing which go bad, usually
without any visible clue, and the layout is hardly service-friendly.

Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427 IIRC.

Four-gang (once again, IIRC) tuner, all analog, silver face, wood cabinet,
rectangular metal knobs, and lots of 14 volts lead-lamps which burn out...

mark Z.

Dave wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.


Thanks for the information all.

Yes there are 4 heat sinked bipolar transsitors. They cost about $10
each. They get warm to the touch.

I bought a service manual for $15 bucks.

I will see what I can find out. This was a friend's unit.

I wil check out those fusible resistors.

If there's no sound I think I'd look at the regulated power supply areas
first...

Mark Z.

"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427 IIRC.

Four-gang (once again, IIRC) tuner, all analog, silver face, wood cabinet,
rectangular metal knobs, and lots of 14 volts lead-lamps which burn out...

mark Z.

I was being facetious Mark, and referring to the fact that it's layout is
not very service friendly ...I went to a Yammy training seminar recently,
and the national service manager told us that the average turnaround time on
an AV amp for a Yammy dealer, was 22 days, which was really too long, and
could anyone venture a suggestion as to why this was. I told him that the
first 16 days were spent looking at it sitting on the shelf, hoping that it
would go away. The next 3 were spent trying to work out what the internal
diagnostics were trying to tell you. The next 1 was spent trying to strip it
apart and work out which screw was still holding it. The next day was spent
fixing it and putting it back together, and the final day was spent either
rejoicing that you could write a bill out for it, or crying whilst watching
all the magic smoke being released again ...!! Sound about right ? d;~}

Arfa

Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer
has any sound output. The meters still show signal strenght when
a tune across the AM/FM bands but I get no audio from the
speakers or the phone jack. No hiss. hum, carckle or pops. JUst
solid dead silence. It isn't worth sending out for a shop base
repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown
) fuse, then it's most likely that the speaker protection circuit
is operating because of a blown output stage. I've a vague
recollection that this one uses an output hybrid ( big black "IC"
bolted to the heatsink with type STK-xxx ) and if so, it is
likely that this is your problem. Some of these can be very
expensive, and many of the older ones are now obsolete and hard
to obtain. If it is one of the models that uses discrete output
stages, then you might struggle to get to the bottom of its
problems, particularly without a set of schematics, which again,
might be difficult to find for an item this old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427
IIRC. Four-gang (once again, IIRC) tuner, all analog, silver face, wood
cabinet, rectangular metal knobs, and lots of 14 volts lead-lamps
which burn out... mark Z.

I was being facetious Mark, and referring to the fact that it's
layout is not very service friendly ...I went to a Yammy training
seminar recently, and the national service manager told us that the
average turnaround time on an AV amp for a Yammy dealer, was 22 days,
which was really too long, and could anyone venture a suggestion as
to why this was. I told him that the first 16 days were spent looking
at it sitting on the shelf, hoping that it would go away. The next 3
were spent trying to work out what the internal diagnostics were
trying to tell you. The next 1 was spent trying to strip it apart and
work out which screw was still holding it. The next day was spent
fixing it and putting it back together, and the final day was spent
either rejoicing that you could write a bill out for it, or crying
whilst watching all the magic smoke being released again ...!! Sound
about right ? d;~}
Arfa

Sound
about right ? d;~}

Absolutely. I just got in an RX-Z9, lightning struck. Can't tell you how
much I'm looking forward to that one...

Mark Z.

Mark D. Zacharias wrote:
Dave wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?



If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa
The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

Thanks for the information all.

Yes there are 4 heat sinked bipolar transsitors. They cost about $10
each. They get warm to the touch.

I bought a service manual for $15 bucks.

I will see what I can find out. This was a friend's unit.

I wil check out those fusible resistors.

If there's no sound I think I'd look at the regulated power supply areas
first...

Mark Z.



It appears one of the output devices is shorted. For $5 I may try a
repair. I did not see the fusible resistors. There is also a relay. I
suppose it could be bad.This doesn't seem to hard to get to many of the
components.



It looks like one of the power stages was repaired before as it use RCA
SK---- devices.

"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427 IIRC.

Four-gang (once again, IIRC) tuner, all analog, silver face, wood cabinet,
rectangular metal knobs, and lots of 14 volts lead-lamps which burn out...

mark Z.


.. If I run the amp with both left channel transistors out of the circuit the
right channel works fine.
I replaced a bad outout transistor after checking it. Now when I turn the
receiver on the main power fuse blows.

My guess is that the original failure took out the power transistor before
the fuse blew.

Dave wrote:

"Mark D. Zacharias" wrote in message
et...

Arfa Daily wrote:

"Mark D. Zacharias" wrote in message
gy.net...

Arfa Daily wrote:

"Dave" wrote in message
digy.net...

I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.


OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427 IIRC.

Four-gang (once again, IIRC) tuner, all analog, silver face, wood cabinet,
rectangular metal knobs, and lots of 14 volts lead-lamps which burn out...

mark Z.



. If I run the amp with both left channel transistors out of the circuit the
right channel works fine.
I replaced a bad outout transistor after checking it. Now when I turn the
receiver on the main power fuse blows.

My guess is that the original failure took out the power transistor before
the fuse blew.



or you put something in wrong.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

"Dave" wrote in
et:


"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer
has any sound output. The meters still show signal strenght when
a tune across the AM/FM bands but I get no audio from the
speakers or the phone jack. No hiss. hum, carckle or pops. JUst
solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown
) fuse, then it's most likely that the speaker protection circuit
is operating because of a blown output stage. I've a vague
recollection that this one uses an output hybrid ( big black "IC"
bolted to the heatsink with type STK-xxx ) and if so, it is likely
that this is your problem. Some of these can be very expensive,
and many of the older ones are now obsolete and hard to obtain. If
it is one of the models that uses discrete output stages, then you
might struggle to get to the bottom of its problems, particularly
without a set of schematics, which again, might be difficult to
find for an item this old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427
IIRC.

Four-gang (once again, IIRC) tuner, all analog, silver face, wood
cabinet, rectangular metal knobs, and lots of 14 volts lead-lamps
which burn out...

mark Z.


. If I run the amp with both left channel transistors out of the
circuit the right channel works fine.
I replaced a bad outout transistor after checking it. Now when I turn
the receiver on the main power fuse blows.

My guess is that the original failure took out the power transistor
before the fuse blew.




Your best bet is to replace all output transistors (left and right
chanel), check all the smaller transistors in the area, and check the
emitter resistors for the outputs (usually 2 small value {~.47 ohms or
less} resistors in one 3 pin package with a common leg in the middle)

----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

"Dave" wrote in message
et...

"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427 IIRC.

Four-gang (once again, IIRC) tuner, all analog, silver face, wood
cabinet, rectangular metal knobs, and lots of 14 volts lead-lamps which
burn out...

mark Z.


. If I run the amp with both left channel transistors out of the circuit
the right channel works fine.
I replaced a bad outout transistor after checking it. Now when I turn the
receiver on the main power fuse blows.

My guess is that the original failure took out the power transistor before
the fuse blew.


Welcome to the world of DC coupled amp repairs ...

Arfa

"Mark D. Zacharias" wrote in message
t...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer
has any sound output. The meters still show signal strenght when
a tune across the AM/FM bands but I get no audio from the
speakers or the phone jack. No hiss. hum, carckle or pops. JUst
solid dead silence. It isn't worth sending out for a shop base
repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown
) fuse, then it's most likely that the speaker protection circuit
is operating because of a blown output stage. I've a vague
recollection that this one uses an output hybrid ( big black "IC"
bolted to the heatsink with type STK-xxx ) and if so, it is
likely that this is your problem. Some of these can be very
expensive, and many of the older ones are now obsolete and hard
to obtain. If it is one of the models that uses discrete output
stages, then you might struggle to get to the bottom of its
problems, particularly without a set of schematics, which again,
might be difficult to find for an item this old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427
IIRC. Four-gang (once again, IIRC) tuner, all analog, silver face, wood
cabinet, rectangular metal knobs, and lots of 14 volts lead-lamps
which burn out... mark Z.

I was being facetious Mark, and referring to the fact that it's
layout is not very service friendly ...I went to a Yammy training
seminar recently, and the national service manager told us that the
average turnaround time on an AV amp for a Yammy dealer, was 22 days,
which was really too long, and could anyone venture a suggestion as
to why this was. I told him that the first 16 days were spent looking
at it sitting on the shelf, hoping that it would go away. The next 3
were spent trying to work out what the internal diagnostics were
trying to tell you. The next 1 was spent trying to strip it apart and
work out which screw was still holding it. The next day was spent
fixing it and putting it back together, and the final day was spent
either rejoicing that you could write a bill out for it, or crying
whilst watching all the magic smoke being released again ...!! Sound
about right ? d;~}
Arfa

Sound
about right ? d;~}

Absolutely. I just got in an RX-Z9, lightning struck. Can't tell you how
much I'm looking forward to that one...

Mark Z.

Hey Mark

Have you done much with the RX-Z1/DSP-AZ1 ? Have you had any problems with
the 4 pin 5v regs? I've got one in at the moment. Runs absolutely fine for
about 20 mins, then starts cutting out, back to standby. Re-powers with
standby switch, but about 1 second only. Diagnostic memory says PS Prot :
016 K/L and then some stuff referring to the processor rev numbers. Don't
know about you, but I have a hard time ever making any sense out of those
Yammy diag messages. " PS " rather than " DC " says power supply rather than
output offset protect, but what is " 016 " trying to tell me ? I seem to
recall that it refers to a percentage error on a rail, but that there are
two different schemes used for the reference. Today, I went down the path of
pulling out the sub psu board to the point where I could get at it to take
some measurements on all the regs on there. With the meter on peak hold, I
caught the output of IC451 going up to 8.54v just before it tripped out. Now
I reckon that's about 160% up on the correct 5v, so is that what " 016 " is
trying to say ? Interested as to whether you have had anything similar. I've
got a replacement coming tomorrow, so should know within 20 minutes of turn
on, but already, no matter what I charge for the repair, I'm actually going
to be down when you count in all the time to dismantle, trouble shoot, and
reassemble. Without doubt, I'd have to say that Yammies are among the worst
of the current crop of AV amps for service and repair. They are just not
friendly at all in any area - electronic design, mechanical design and user
interface.

Arfa

Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
t...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer
has any sound output. The meters still show signal strenght
when a tune across the AM/FM bands but I get no audio from the
speakers or the phone jack. No hiss. hum, carckle or pops. JUst
solid dead silence. It isn't worth sending out for a shop base
repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than
blown ) fuse, then it's most likely that the speaker protection
circuit is operating because of a blown output stage. I've a
vague recollection that this one uses an output hybrid ( big
black "IC" bolted to the heatsink with type STK-xxx ) and if
so, it is likely that this is your problem. Some of these can
be very expensive, and many of the older ones are now obsolete
and hard to obtain. If it is one of the models that uses
discrete output stages, then you might struggle to get to the
bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item
this old. Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which
go bad, usually without any visible clue, and the layout is
hardly service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427
IIRC. Four-gang (once again, IIRC) tuner, all analog, silver face,
wood cabinet, rectangular metal knobs, and lots of 14 volts
lead-lamps which burn out... mark Z.

I was being facetious Mark, and referring to the fact that it's
layout is not very service friendly ...I went to a Yammy training
seminar recently, and the national service manager told us that the
average turnaround time on an AV amp for a Yammy dealer, was 22
days, which was really too long, and could anyone venture a
suggestion as to why this was. I told him that the first 16 days
were spent looking at it sitting on the shelf, hoping that it would
go away. The next 3 were spent trying to work out what the internal
diagnostics were trying to tell you. The next 1 was spent trying to
strip it apart and work out which screw was still holding it. The
next day was spent fixing it and putting it back together, and the
final day was spent either rejoicing that you could write a bill
out for it, or crying whilst watching all the magic smoke being
released again ...!! Sound about right ? d;~}
Arfa

Sound
about right ? d;~}

Absolutely. I just got in an RX-Z9, lightning struck. Can't tell you
how much I'm looking forward to that one...

Mark Z.

Hey Mark

Have you done much with the RX-Z1/DSP-AZ1 ? Have you had any problems
with the 4 pin 5v regs? I've got one in at the moment. Runs
absolutely fine for about 20 mins, then starts cutting out, back to
standby. Re-powers with standby switch, but about 1 second only.
Diagnostic memory says PS Prot : 016 K/L and then some stuff
referring to the processor rev numbers. Don't know about you, but I
have a hard time ever making any sense out of those Yammy diag
messages. " PS " rather than " DC " says power supply rather than
output offset protect, but what is " 016 " trying to tell me ? I
seem to recall that it refers to a percentage error on a rail, but
that there are two different schemes used for the reference. Today, I
went down the path of pulling out the sub psu board to the point
where I could get at it to take some measurements on all the regs on
there. With the meter on peak hold, I caught the output of IC451
going up to 8.54v just before it tripped out. Now I reckon that's
about 160% up on the correct 5v, so is that what " 016 " is trying to
say ? Interested as to whether you have had anything similar. I've
got a replacement coming tomorrow, so should know within 20 minutes
of turn on, but already, no matter what I charge for the repair, I'm
actually going to be down when you count in all the time to
dismantle, trouble shoot, and reassemble. Without doubt, I'd have to
say that Yammies are among the worst of the current crop of AV amps
for service and repair. They are just not friendly at all in any area
- electronic design, mechanical design and user interface.
Arfa

I have had that exact problem on one - and the regulator fixed it just
fine - no other damage done.

I've never bothered to try to decipher those DC error levels. They are based
on 5 volts, as I recall.

Mark Z.

"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
t...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer
has any sound output. The meters still show signal strenght
when a tune across the AM/FM bands but I get no audio from the
speakers or the phone jack. No hiss. hum, carckle or pops. JUst
solid dead silence. It isn't worth sending out for a shop base
repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than
blown ) fuse, then it's most likely that the speaker protection
circuit is operating because of a blown output stage. I've a
vague recollection that this one uses an output hybrid ( big
black "IC" bolted to the heatsink with type STK-xxx ) and if
so, it is likely that this is your problem. Some of these can
be very expensive, and many of the older ones are now obsolete
and hard to obtain. If it is one of the models that uses
discrete output stages, then you might struggle to get to the
bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item
this old. Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which
go bad, usually without any visible clue, and the layout is
hardly service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427
IIRC. Four-gang (once again, IIRC) tuner, all analog, silver face,
wood cabinet, rectangular metal knobs, and lots of 14 volts
lead-lamps which burn out... mark Z.

I was being facetious Mark, and referring to the fact that it's
layout is not very service friendly ...I went to a Yammy training
seminar recently, and the national service manager told us that the
average turnaround time on an AV amp for a Yammy dealer, was 22
days, which was really too long, and could anyone venture a
suggestion as to why this was. I told him that the first 16 days
were spent looking at it sitting on the shelf, hoping that it would
go away. The next 3 were spent trying to work out what the internal
diagnostics were trying to tell you. The next 1 was spent trying to
strip it apart and work out which screw was still holding it. The
next day was spent fixing it and putting it back together, and the
final day was spent either rejoicing that you could write a bill
out for it, or crying whilst watching all the magic smoke being
released again ...!! Sound about right ? d;~}
Arfa

Sound
about right ? d;~}

Absolutely. I just got in an RX-Z9, lightning struck. Can't tell you
how much I'm looking forward to that one...

Mark Z.

Hey Mark

Have you done much with the RX-Z1/DSP-AZ1 ? Have you had any problems
with the 4 pin 5v regs? I've got one in at the moment. Runs
absolutely fine for about 20 mins, then starts cutting out, back to
standby. Re-powers with standby switch, but about 1 second only.
Diagnostic memory says PS Prot : 016 K/L and then some stuff
referring to the processor rev numbers. Don't know about you, but I
have a hard time ever making any sense out of those Yammy diag
messages. " PS " rather than " DC " says power supply rather than
output offset protect, but what is " 016 " trying to tell me ? I
seem to recall that it refers to a percentage error on a rail, but
that there are two different schemes used for the reference. Today, I
went down the path of pulling out the sub psu board to the point
where I could get at it to take some measurements on all the regs on
there. With the meter on peak hold, I caught the output of IC451
going up to 8.54v just before it tripped out. Now I reckon that's
about 160% up on the correct 5v, so is that what " 016 " is trying to
say ? Interested as to whether you have had anything similar. I've
got a replacement coming tomorrow, so should know within 20 minutes
of turn on, but already, no matter what I charge for the repair, I'm
actually going to be down when you count in all the time to
dismantle, trouble shoot, and reassemble. Without doubt, I'd have to
say that Yammies are among the worst of the current crop of AV amps
for service and repair. They are just not friendly at all in any area
- electronic design, mechanical design and user interface.
Arfa

I have had that exact problem on one - and the regulator fixed it just
fine - no other damage done.

I've never bothered to try to decipher those DC error levels. They are
based on 5 volts, as I recall.

Mark Z.

OK, well that's good to know. The reg didn't actually turn up today, so
hopefully tomorrow. You are right that the error figures do relate to 5v - I
can remember the little Japanese guy that lectured me on it originally,
saying so, but his english was not too good, and I was having enough trouble
just trying to stay with that, let alone the in-depth meaning of what he was
actually saying. I definitely do remember him saying that there were two
different schemes as to how the figure related to 5v though. Shame really,
as he was a very clever guy, and clearly knew these beasts inside out, but
boy, was his lecture hard work to understand, just purely from the
linguistic point of view.

And then, of course, we had Mr Beardy in the class, who stopped the poor
little guy every six sentences, and took him, and the whole class, off on a
tangent about some obscure problem that he'd had 10 years ago, for 15
minutes. I'm sure that you've been there ...

Thanks for confirming my suspicions about the 5v reg - I'll let you know !

Arfa

"Arfa Daily" wrote in message
...

"Dave" wrote in message
et...

"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has
any sound output. The meters still show signal strenght when a tune
across the AM/FM bands but I get no audio from the speakers or the
phone jack. No hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than blown )
fuse, then it's most likely that the speaker protection circuit is
operating because of a blown output stage. I've a vague recollection
that this one uses an output hybrid ( big black "IC" bolted to the
heatsink with type STK-xxx ) and if so, it is likely that this is
your problem. Some of these can be very expensive, and many of the
older ones are now obsolete and hard to obtain. If it is one of the
models that uses discrete output stages, then you might struggle to
get to the bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item this
old.
Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which go
bad, usually without any visible clue, and the layout is hardly
service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427 IIRC.

Four-gang (once again, IIRC) tuner, all analog, silver face, wood
cabinet, rectangular metal knobs, and lots of 14 volts lead-lamps which
burn out...

mark Z.


. If I run the amp with both left channel transistors out of the circuit
the right channel works fine.
I replaced a bad outout transistor after checking it. Now when I turn the
receiver on the main power fuse blows.

My guess is that the original failure took out the power transistor
before the fuse blew.


Welcome to the world of DC coupled amp repairs ...

Arfa

It has been fun playing with this. I salvaged it from the recycling heap. It
looks like I will be scraping it an dselling the parts on eBay.

Thanks all for the information.

It has been fun playing with this. I salvaged it from the recycling heap. It
looks like I will be scraping it an dselling the parts on eBay.

Wait! When an output device goes, doesn't it frequently take the driver stage
transistor with it? Look back "up" the power output train for a shorted
tranny before binning it.
--
DaveC

This is an invalid return address
Please reply in the news group

"DaveC" wrote in message
obal.net...
It has been fun playing with this. I salvaged it from the recycling heap.
It
looks like I will be scraping it an dselling the parts on eBay.

Wait! When an output device goes, doesn't it frequently take the driver
stage
transistor with it? Look back "up" the power output train for a shorted
tranny before binning it.
--
DaveC

This is an invalid return address
Please reply in the news group


I will give that a look before I do anything. All I have is a couple DVMs
and a transistor checker but I can do quite a bit with this limited test
package!

will give that a look before I do anything. All I have is a couple DVMs
and a transistor checker but I can do quite a bit with this limited test
package!

"Continuity" setting on your DVM is all you'll need, probably (c:
--
DaveC

This is an invalid return address
Please reply in the news group

"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer has any
sound output. The meters still show signal strenght when a tune across the
AM/FM bands but I get no audio from the speakers or the phone jack. No
hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can obtain a
schematic or service manual?




Have you plugged in a CD player to it yet?

"Arfa Daily" wrote in message
...

"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
t...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no longer
has any sound output. The meters still show signal strenght
when a tune across the AM/FM bands but I get no audio from the
speakers or the phone jack. No hiss. hum, carckle or pops. JUst
solid dead silence. It isn't worth sending out for a shop base
repair.

Has anyone has a similar problem? Does anyone know where I can
obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than
blown ) fuse, then it's most likely that the speaker protection
circuit is operating because of a blown output stage. I've a
vague recollection that this one uses an output hybrid ( big
black "IC" bolted to the heatsink with type STK-xxx ) and if
so, it is likely that this is your problem. Some of these can
be very expensive, and many of the older ones are now obsolete
and hard to obtain. If it is one of the models that uses
discrete output stages, then you might struggle to get to the
bottom of its problems, particularly without a set of
schematics, which again, might be difficult to find for an item
this old. Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing which
go bad, usually without any visible clue, and the layout is
hardly service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and 2SD427
IIRC. Four-gang (once again, IIRC) tuner, all analog, silver face,
wood cabinet, rectangular metal knobs, and lots of 14 volts
lead-lamps which burn out... mark Z.

I was being facetious Mark, and referring to the fact that it's
layout is not very service friendly ...I went to a Yammy training
seminar recently, and the national service manager told us that the
average turnaround time on an AV amp for a Yammy dealer, was 22
days, which was really too long, and could anyone venture a
suggestion as to why this was. I told him that the first 16 days
were spent looking at it sitting on the shelf, hoping that it would
go away. The next 3 were spent trying to work out what the internal
diagnostics were trying to tell you. The next 1 was spent trying to
strip it apart and work out which screw was still holding it. The
next day was spent fixing it and putting it back together, and the
final day was spent either rejoicing that you could write a bill
out for it, or crying whilst watching all the magic smoke being
released again ...!! Sound about right ? d;~}
Arfa

Sound
about right ? d;~}

Absolutely. I just got in an RX-Z9, lightning struck. Can't tell you
how much I'm looking forward to that one...

Mark Z.

Hey Mark

Have you done much with the RX-Z1/DSP-AZ1 ? Have you had any problems
with the 4 pin 5v regs? I've got one in at the moment. Runs
absolutely fine for about 20 mins, then starts cutting out, back to
standby. Re-powers with standby switch, but about 1 second only.
Diagnostic memory says PS Prot : 016 K/L and then some stuff
referring to the processor rev numbers. Don't know about you, but I
have a hard time ever making any sense out of those Yammy diag
messages. " PS " rather than " DC " says power supply rather than
output offset protect, but what is " 016 " trying to tell me ? I
seem to recall that it refers to a percentage error on a rail, but
that there are two different schemes used for the reference. Today, I
went down the path of pulling out the sub psu board to the point
where I could get at it to take some measurements on all the regs on
there. With the meter on peak hold, I caught the output of IC451
going up to 8.54v just before it tripped out. Now I reckon that's
about 160% up on the correct 5v, so is that what " 016 " is trying to
say ? Interested as to whether you have had anything similar. I've
got a replacement coming tomorrow, so should know within 20 minutes
of turn on, but already, no matter what I charge for the repair, I'm
actually going to be down when you count in all the time to
dismantle, trouble shoot, and reassemble. Without doubt, I'd have to
say that Yammies are among the worst of the current crop of AV amps
for service and repair. They are just not friendly at all in any area
- electronic design, mechanical design and user interface.
Arfa

I have had that exact problem on one - and the regulator fixed it just
fine - no other damage done.

I've never bothered to try to decipher those DC error levels. They are
based on 5 volts, as I recall.

Mark Z.

OK, well that's good to know. The reg didn't actually turn up today, so
hopefully tomorrow. You are right that the error figures do relate to 5v -
I can remember the little Japanese guy that lectured me on it originally,
saying so, but his english was not too good, and I was having enough
trouble just trying to stay with that, let alone the in-depth meaning of
what he was actually saying. I definitely do remember him saying that
there were two different schemes as to how the figure related to 5v
though. Shame really, as he was a very clever guy, and clearly knew these
beasts inside out, but boy, was his lecture hard work to understand, just
purely from the linguistic point of view.

And then, of course, we had Mr Beardy in the class, who stopped the poor
little guy every six sentences, and took him, and the whole class, off on
a tangent about some obscure problem that he'd had 10 years ago, for 15
minutes. I'm sure that you've been there ...

Thanks for confirming my suspicions about the 5v reg - I'll let you know !

Arfa

Mark

Reg chip arrived. Fitted Friday morning. Still running Friday night, so I
guess we got us a result !

Arfa

Arfa Daily wrote:
"Arfa Daily" wrote in message
...

"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
t...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
et...
Arfa Daily wrote:
"Mark D. Zacharias" wrote in message
. net...
Arfa Daily wrote:
"Dave" wrote in message
. net...
I have an old Yamaha CR-820 receiver/amplifier that no
longer has any sound output. The meters still show signal
strenght when a tune across the AM/FM bands but I get no
audio from the speakers or the phone jack. No hiss. hum,
carckle or pops. JUst solid dead silence. It isn't worth
sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I
can obtain a schematic or service manual?




If it's nothing straightforward like a failed ( rather than
blown ) fuse, then it's most likely that the speaker
protection circuit is operating because of a blown output
stage. I've a vague recollection that this one uses an
output hybrid ( big black "IC" bolted to the heatsink with
type STK-xxx ) and if so, it is likely that this is your
problem. Some of these can be very expensive, and many of
the older ones are now obsolete and hard to obtain. If it is
one of the models that uses discrete output stages, then you
might struggle to get to the bottom of its problems,
particularly without a set of schematics, which again, might
be difficult to find for an item this old. Arfa

The CR-820 uses discrete transistors, but the repair isn't for
newbies - there's fusible resistors inside asbestos tubing
which go bad, usually without any visible clue, and the
layout is hardly service-friendly. Mark Z.

OK, much like the modern Yammy AV amps then ...

Arfa

Well, they aren't flat packs - they're TO-3's - 2SB557 and
2SD427 IIRC. Four-gang (once again, IIRC) tuner, all analog,
silver face, wood cabinet, rectangular metal knobs, and lots of
14 volts lead-lamps which burn out... mark Z.

I was being facetious Mark, and referring to the fact that it's
layout is not very service friendly ...I went to a Yammy training
seminar recently, and the national service manager told us that
the average turnaround time on an AV amp for a Yammy dealer, was
22 days, which was really too long, and could anyone venture a
suggestion as to why this was. I told him that the first 16 days
were spent looking at it sitting on the shelf, hoping that it
would go away. The next 3 were spent trying to work out what the
internal diagnostics were trying to tell you. The next 1 was
spent trying to strip it apart and work out which screw was
still holding it. The next day was spent fixing it and putting
it back together, and the final day was spent either rejoicing
that you could write a bill out for it, or crying whilst
watching all the magic smoke being released again ...!! Sound
about right ? d;~} Arfa

Sound
about right ? d;~}

Absolutely. I just got in an RX-Z9, lightning struck. Can't tell
you how much I'm looking forward to that one...

Mark Z.

Hey Mark

Have you done much with the RX-Z1/DSP-AZ1 ? Have you had any
problems with the 4 pin 5v regs? I've got one in at the moment.
Runs absolutely fine for about 20 mins, then starts cutting out,
back to standby. Re-powers with standby switch, but about 1 second
only. Diagnostic memory says PS Prot : 016 K/L and then some
stuff referring to the processor rev numbers. Don't know about
you, but I have a hard time ever making any sense out of those
Yammy diag messages. " PS " rather than " DC " says power supply
rather than output offset protect, but what is " 016 " trying to
tell me ? I seem to recall that it refers to a percentage error on
a rail, but that there are two different schemes used for the
reference. Today, I went down the path of pulling out the sub psu
board to the point where I could get at it to take some
measurements on all the regs on there. With the meter on peak
hold, I caught the output of IC451 going up to 8.54v just before
it tripped out. Now I reckon that's about 160% up on the correct
5v, so is that what " 016 " is trying to say ? Interested as to
whether you have had anything similar. I've got a replacement
coming tomorrow, so should know within 20 minutes of turn on, but
already, no matter what I charge for the repair, I'm actually
going to be down when you count in all the time to dismantle,
trouble shoot, and reassemble. Without doubt, I'd have to say that
Yammies are among the worst of the current crop of AV amps for
service and repair. They are just not friendly at all in any area
- electronic design, mechanical design and user interface. Arfa

I have had that exact problem on one - and the regulator fixed it
just fine - no other damage done.

I've never bothered to try to decipher those DC error levels. They
are based on 5 volts, as I recall.

Mark Z.

OK, well that's good to know. The reg didn't actually turn up today,
so hopefully tomorrow. You are right that the error figures do
relate to 5v - I can remember the little Japanese guy that lectured
me on it originally, saying so, but his english was not too good,
and I was having enough trouble just trying to stay with that, let
alone the in-depth meaning of what he was actually saying. I
definitely do remember him saying that there were two different
schemes as to how the figure related to 5v though. Shame really, as
he was a very clever guy, and clearly knew these beasts inside out,
but boy, was his lecture hard work to understand, just purely from
the linguistic point of view. And then, of course, we had Mr Beardy in
the class, who stopped the
poor little guy every six sentences, and took him, and the whole
class, off on a tangent about some obscure problem that he'd had 10
years ago, for 15 minutes. I'm sure that you've been there ...

Thanks for confirming my suspicions about the 5v reg - I'll let you
know ! Arfa

Mark

Reg chip arrived. Fitted Friday morning. Still running Friday night,
so I guess we got us a result !

Arfa

Woo-Hoo!

mz

On Apr 18, 2:43 pm, "Paul Feaker" wrote:
"Dave" wrote in message

. net...

I have an old Yamaha CR-820 receiver/amplifier that no longer has any
sound output. The meters still show signal strenght when a tune across the
AM/FM bands but I get no audio from the speakers or the phone jack. No
hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can obtain a
schematic or service manual?

Have you plugged in a CD player to it yet?

Why would anybody plug in a CD player to a broken stereo stupid?

"Sitre Magana" wrote in message
ups.com...
On Apr 18, 2:43 pm, "Paul Feaker" wrote:
"Dave" wrote in message

. net...

I have an old Yamaha CR-820 receiver/amplifier that no longer has any
sound output. The meters still show signal strenght when a tune across
the
AM/FM bands but I get no audio from the speakers or the phone jack. No
hiss. hum, carckle or pops. JUst solid dead silence.

It isn't worth sending out for a shop base repair.

Has anyone has a similar problem? Does anyone know where I can obtain a
schematic or service manual?

Have you plugged in a CD player to it yet?

Why would anybody plug in a CD player to a broken stereo stupid?


That is what I thiought too. I think the post may have been just a "funny".

On Apr 25, 10:38 pm, "Dave" wrote:
"SitreMagana" wrote in message

Why would anybody plug in a CD player to a broken stereo stupid?


Methinks so you can rule out the tuner, If you plug in a CD player and
you hear music, then you can be sure that the tuner is ****ed.
But if you don't then you work from there.

That is what I thiought too. I think the post may have been just a "funny".- Hide quoted text -

You want to know what else is funny: You and Sitre Magana is a gay
porno video, asshole.

"Brittany Martin" wrote in message
oups.com...
On Apr 25, 10:38 pm, "Dave" wrote:
"SitreMagana" wrote in message

Why would anybody plug in a CD player to a broken stereo stupid?


Methinks so you can rule out the tuner, If you plug in a CD player and
you hear music, then you can be sure that the tuner is ****ed.
But if you don't then you work from there.

That is what I thiought too. I think the post may have been just a
"funny".- Hide quoted text -

You want to know what else is funny: You and Sitre Magana is a gay
porno video, asshole.


I know the tuner works.

Your a real asset to the newsgroup.