Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

Hello all...

This is part of a longer story which I won't get into now. Suffice it
to say that I've wanted to get my hands on a failed Sherwood RX-4105
or RX-4109 stereo receiver to see just what it is that kills
them...abuse, misuse, weak parts, bad engineering/quality control or
something else. I've never had any luck coming into a truly broken
one, but someone recently gave me an RX-5502 that would just shut down
right after power on. I've been very happy with all of the RX-4105 and
4109 units I own.

The RX-5502 is a so-called multi-zone receiver. That is to say it can
support up to eight connected pairs of speakers, with four of the
pairs playing a different ("room 2") source if that is desired. It has
two complete stereo amplifiers in place, each one claimed to have an
output power of 100 watts per channel. (Obviously they're dreaming if
they think that this receiver is ever going to output 400 total watts
of power without catching fire, but...) This example was manufactured
sometime in 2008.

As found, this set would indeed power on for a few seconds, and shut
down with a blinking standby LED. I started checking things out. In
this set, the amplifier board is separate from the main board, so this
was not terribly hard to do. Every power device tested good with a
simple ohmmeter check, and nothing looked burnt or distressed on the
amp board. This doesn't look like a case of a failed power transistor
to me.

I'm working without service literature or even a schematic as Sherwood
would not provide them, but there is printing on the board that
identifies what each conductor in the ribbon cable going to the amp
board is used for. This set has a "test mode", and unlike similar
models, the "test mode" allows the power to stay on indefinitely while
the display test is running. Testing for voltages is a lot nicer
without having to constantly turn the set back on again! Voltages are
what I'd expect for B+ and B-, but a twelve volt input to the board is
hovering around a few hundred millivolts at most. That could do it!

Removing the amplifier board from the system and running without it
was probably risky, but it seemed like a worthwhile thing to do. With
the amp board removed, there was still no voltage from the +12 volt
connection. It still hovered around 300mV with the set on.
Interestingly, every now and then, a good power up was possible with
the amp board out, and the set would come out of protection.
Okay...where is the +12 volt supply generated?

Over in the power supply section there are a few linear voltage
regulators--two heatsinked 7812s and one freestanding 7912. One 7812
and the 7912 are doing their jobs, but the other 7812 is cold to the
touch and does not seem to be doing anything. (In fact, it was putting
out 300mV when I later checked it.)

Replacing the failed 7812 with an LM340 solved the problem. The set
immediately came back to life with the amp board in place, and it
plays. It appears, based on simple observation, that one 7812 is
powering the coils leading up to the speaker selection/protection
relays and the other is powering the amp board itself. What other
loads might be powered by these regulators has not been determined.

While the set is working, I don't like the temperature at which the
new regulator is running. Within ten minutes, its heatsink is on the
verge of being too hot to touch for more than a few seconds. There is
evidence on the circuit board that these regulators have always run
very hot. I've been in touch with Sherwood America, who said "the
regulator may become too hot to touch and possibly fail". I strongly
suspect there are bad capacitors on the amp and main boards, which
will need to be replaced and may be stressing the regulator. Yet
Sherwood seems to be saying that the extremely hot operation is
*normal* here. (However, it should be said that there is something of
a language barrier with the folks I've been communicating with.)

I could install a fan above or larger heatsink on the regulator and
I'm not above doing it if that is just the way things will be. I
suspect that would force the regulator to operate more reliably.

What I really want to know, though, is whether or not a drop-in
replacement with more current delivering capability than the LM340 or
78xx series exists. I've looked halfheartedly over the years but never
found anything. I could always build a more capable regulator board
and hack it in there, but I don't really feel like doing that. A fan
would be easier and faster.

I'd also like to know if anyone has had an RX-5502 on their repair
bench, and if they could comment on just how hot its regulators were
running. Any thoughts would be very much appreciated!

Thank you.

William
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

On Oct 12, 10:05*am, "William R. Walsh" wrote:
Hello all...

This is part of a longer story which I won't get into now. Suffice it
to say that I've wanted to get my hands on a failed Sherwood RX-4105
or RX-4109 stereo receiver to see just what it is that kills
them...abuse, misuse, weak parts, bad engineering/quality control or
something else. I've never had any luck coming into a truly broken
one, but someone recently gave me an RX-5502 that would just shut down
right after power on. I've been very happy with all of the RX-4105 and
4109 units I own.


Why would you care so much about some Korean POS? Sherwood was once a
fine Chicago company, from the era when Chicago was the consumer
electronics center of the world.
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

I've been in touch with Sherwood America, who said "the
regulator may become too hot to touch and possibly fail".
William




Well there you go, the manufacturer has backed up your observations that
this regulator does indeed run very hot. Its not that uncommon to find this
kind of thing.

Stick a heatsink on it. Job done.



Gareth.

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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

Hi!

Why would you care so much about some Korean POS?


Well, because I can? Because I like 'em? Because the internal design
is pretty clean and straightforward? Because I like their sound and
think they're a pretty damn good modern receiver? Maybe because it's
just one other thing that won't end up in the landfill? Has the
purpose of this group changed since I was last here?

That's not the question I asked, or the information I wanted. Pulling
out my IR thermometer reveals that the regulator really isn't getting
as hot as I thought it was...about 124F or so at its hottest point.
I'll not worry about it further, though I probably will add a fan
powered by the lesser loaded regulator.

William
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

Hi!

Stick a heatsink on it. *Job done.


It's already got a goodly sized heatsink on it. In fact, I couldn't
find anything bigger in the TO-220 category. Operating temps turn out
not to be as bad as I thought--about 124F at most. Perhaps the
original regulator was just defective. I'll never know.

I will probably just run a fan from the other, less loaded regulator
and suspend it over the circuit board. That would be a lot less work
than milling some scrap heatsinks from old PC power supplies down to
fit.

William


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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

"Gareth Magennis" wrote in message
...
I've been in touch with Sherwood America, who said "the
regulator may become too hot to touch and possibly fail".
William




Well there you go, the manufacturer has backed up your observations that
this regulator does indeed run very hot. Its not that uncommon to find
this kind of thing.

Stick a heatsink on it. Job done.



Gareth.


Sherwood makes receivers for many others, and there is a common problem the
past several years with cheap fixed regulators failing. Mostly 79 series 12
and 15 volt regs but also 78 series positive types. They are heatsinked, but
fail anyway.

Mark Z.

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On Oct 12, 2:53*pm, "William R. Walsh" wrote:
Hi!

Why would you care so much about some Korean POS?


Well, because I can? Because I like 'em? Because the internal design
is pretty clean and straightforward? Because I like their sound and
think they're a pretty damn good modern receiver? Maybe because it's
just one other thing that won't end up in the landfill? Has the
purpose of this group changed since I was last here?


Your purpose in coming here seemed quite quixotic, not to say
masochistic, and therefore provoked curiosity:

"Suffice it to say that I've wanted to get my hands on a failed
Sherwood RX-4105 or RX-4109 stereo receiver to see just what it is
that kills them...abuse, misuse, weak parts, bad engineering/quality
control or something else. "

Hard to imagine anything other than frequent failure would provoke
this quest. A likely parallel in the automotive world would be a
mission to isolate failure modes of the Yugo.

Regarding the purpose of the group: Generally people come here to get
information to help them repair various pieces of electronic
equipment, often because their livelihood depends on it. Instead, you
want advice so you can redesign this run of the mill receiver for
greater reliability.


That's not the question I asked, or the information I wanted. Pulling
out my IR thermometer reveals that the regulator really isn't getting
as hot as I thought it was...about 124F or so at its hottest point.
I'll not worry about it further, though I probably will add a fan
powered by the lesser loaded regulator.


Why clutter up such a clean and straightforward internal design with
adequate cooling?
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

On Wed, 12 Oct 2011 10:05:18 -0700 (PDT), "William R. Walsh"
wrote:

(snip)

What I really want to know, though, is whether or not a drop-in
replacement with more current delivering capability than the LM340 or
78xx series exists. I've looked halfheartedly over the years but never
found anything. I could always build a more capable regulator board
and hack it in there, but I don't really feel like doing that. A fan
would be easier and faster.


Alternative 3-terminal linear regs will still dissipate the same
amount of heat regardless of their current capability.

If the problem is in the load (i.e. faulty components) then that
should be where you focus your attention.

If the real problem is the load current and the consequent thermal
issues (i.e marginal/poor design vs SOA) then measure the actual load
current and consider a drop-in switcher such as the (TI) PT78T112V or
(RECOM) R-7812.
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughtswanted...

On 10/12/2011 12:05 PM, William R. Walsh wrote:
What I really want to know, though, is whether or not a drop-in
replacement with more current delivering capability than the LM340 or
78xx series exists.


Actually, it sounds more like they blew the design by having too
much input voltage for the output voltage and current.

As a modest example of what I mean:
18V input 12V output at 1 amp. This is 6 watts dissipation at
the regulator package.
24V input 12V output at 1 amp. This is 12 watts dissipation
at the regulator package.

http://www.datasheetcatalog.org/datasheets2/52/529144_1.pdf

Doesn't specifically give a voltage drop vs output current
derating curve. But I would think that adding a bit of series
resistance to the input side and letting some of the waste
heat go away there would go a long way towards extending the
life of the regulator package.

Jeff

--
"Everything from Crackers to Coffins"
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"William R. Walsh" wrote in message
...
Hi!

Stick a heatsink on it. Job done.


It's already got a goodly sized heatsink on it. In fact, I couldn't
find anything bigger in the TO-220 category. Operating temps turn out
not to be as bad as I thought--about 124F at most. Perhaps the
original regulator was just defective. I'll never know.

I will probably just run a fan from the other, less loaded regulator
and suspend it over the circuit board. That would be a lot less work
than milling some scrap heatsinks from old PC power supplies down to
fit.

William



Oops, should have read your post properly, it was a long hard day yesterday
and today I have aches and pains to remind me.


Gareth.



Gareth.



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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

On Wed, 12 Oct 2011 10:05:18 -0700 (PDT) "William R. Walsh"
wrote in Message id:
:


What I really want to know, though, is whether or not a drop-in
replacement with more current delivering capability than the LM340 or
78xx series exists. I've looked halfheartedly over the years but never
found anything. I could always build a more capable regulator board
and hack it in there, but I don't really feel like doing that. A fan
would be easier and faster.


These will go up to 3A.
http://search.digikey.com/us/en/prod...1118-ND/771587

Bottom line is that it's the heatsink and the voltage in that will
determine whether you'll actually get 3A.
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

Hi!

Your purpose in coming here seemed quite quixotic, not to
say masochistic, and therefore provoked curiosity:


I've never been described in quite that way before. ;-)

Hard to imagine anything other than frequent failure would
provoke this quest.


To the contrary...I have a number of these sets used in various
applications. All are well treated and used under reasonable
conditions. I've never had a failure, even when making heavy demands
from the set. The one time I accidentally shorted a pair of speaker
wires, the set's protection functioned just as it should and there was
no lasting damage.

Yet I look around on the 'net and see people saying "well, the
Sherwood unit blew up, blew sparks and smoke, shuts off past a certain
volume level or just shut down one day, never to turn on again". What
few repairs I've seen done suggested that blown final transistors or
bad filter caps were the cause. My experiences don't align with what
people were saying.

I have no particularly good reason for wanting to know other than to
say I am eternally curious. "Why?" is one of my favorite questions. As
proof that I have no shortage of obnoxious opinions, troubleshooting
and repairing this receiver was arguably more worthwhile than watching
what passes for television these days.

Regarding the purpose of the group: Generally people come here to get
information to help them repair various pieces of electronic
equipment, often because their livelihood depends on it. Instead, you
want advice so you can redesign this run of the mill receiver for
greater reliability.


Not totally. I wanted to share what I found, in the case that other
people here, who might someday be faced with the same situation, could
potentially find a solution. Though I've not been here for a while, I
am not new to the group or its purpose. Your initial response was
taken to mean more of a "why would I bother repairing that piece of
junk".

If I think that something I've repaired could break in the same way,
making a better repair or improvement to the design is something I'd
go ahead and do, provided it does not involve a massive reworking. As
I have never found any simple linear regulator better spec'd than the
78xx series, I thought I'd throw the question in while I was here.

I don't do this professionally, nor do I have the audacity to claim
that I am a professional. I'm just someone who knows a modest amount
and takes an interest from the sidelines.

Why clutter up such a clean and straightforward internal design with
adequate cooling?


No doubt the unit was designed to a price. Who could say what the
original designers had in mind...or maybe they just made a mistake.

It has to be said that Sherwood has been (mostly) helpful along the
course of this repair, much more so than the competion (Sony and
TEAC).

William
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

Hi!

Alternative 3-terminal linear regs will still dissipate the same
amount of heat regardless of their current capability.


Okay...if you don't mind my asking, why is that the case? It would
seem to me that a more capable part asked to do the same work as a
less capable part would have an easier time of it.

If the problem is in the load (i.e. faulty components) then that
should be where you focus your attention.


There does not appear to be any problem with anything that is powered
by the regulator's output (though I do have some suspicious caps to
replace elsewhere).

William
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Hi!

Actually, it sounds more like they blew the design by having too
much input voltage for the output voltage and current.


The regulator is supplied with 25 volts. While I hadn't really looked
at the curves and figures, what they are doing did not sit well with
me from the outset. Why ask the regulator to do that much work?

But I would think that adding a bit of series
resistance to the input side and letting some of the waste
heat go away there would go a long way towards extending the
life of the regulator package.


I had not thought of this and might just sit down and do the math to
see what I'd need. What I do will depend upon whether or not there is
room to put something in place without going to extremes.

William
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Hi!

They are heatsinked, but fail anyway.


The regulator I replaced had a fully plastic body, and I wonder if
this did not help to accelerate its demise. The replacement part is a
Motorola/OnSemi LM340 with a metal tab. It seems to me like this would
work better at shedding heat than a fully plastic body.

William


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"William R. Walsh" writes:

Alternative 3-terminal linear regs will still dissipate the same
amount of heat regardless of their current capability.

Okay...if you don't mind my asking, why is that the case?


Because that's how linear regulators work -- they behave like a sort of
intelligent resistor. If you regulate 28V down to 12V with a linear
regulator, the regulator acts like the right value of resistor to get
rid of 16V as heat.

You can do better with more modern regulators, but you need a switching
regulator rather than a linear one. National's "Simple Switcher"
regulators are good for this sort of thing; you pretty much just add an
external capacitor and inductor.

--
Adam Sampson http://offog.org/
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In article ,
Adam Sampson wrote:

Because that's how linear regulators work -- they behave like a sort of
intelligent resistor. If you regulate 28V down to 12V with a linear
regulator, the regulator acts like the right value of resistor to get
rid of 16V as heat.

You can do better with more modern regulators, but you need a switching
regulator rather than a linear one. National's "Simple Switcher"
regulators are good for this sort of thing; you pretty much just add an
external capacitor and inductor.


Murata now has some interesting little switching regulators which
"mimic" a 7805 - they have the same pinout, same current capacity, and
are built on a small PC board which is roughly the size and shape of a
TO-220.

I recently installed one in an old MFJ packet-terminal node controller
(TNC). THe original TNC design uses a 7805, with a small clip-on
heatsink, and a thoroughly-incompetent attempt to couple the heatsink
to the case for additional heat transfer (they gooped the heatsink
surface with silicone compound, but did *not* actually fasten the
heatsink to the case!). Even with the clip-on heatsink, the 7805 was
running quite hot... not too hot to touch, but warmer than I like.

The Murata part dropped right in, requires no heatsink, works nicely,
and it's barely warm to the touch.

As with any decision to substitute a switching regulator for a linear
regulator, you'll need to consider the output noise - it might be too
much for an audio amplifier to tolerate. Or, one or more additional
stages of filtering may be required.

These Murata parts are about $4.50 each in onesies, through Mouser.

--
Dave Platt AE6EO
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On Thu, 13 Oct 2011 08:57:08 -0700 (PDT), "William R. Walsh"
wrote:

Hi!

Alternative 3-terminal linear regs will still dissipate the same
amount of heat regardless of their current capability.


Okay...if you don't mind my asking, why is that the case? It would
seem to me that a more capable part asked to do the same work as a
less capable part would have an easier time of it.


It WILL have an easier time of it but OTOH it will still require
dissipation of the same amount of heat.

If the problem is in the load (i.e. faulty components) then that
should be where you focus your attention.


There does not appear to be any problem with anything that is powered
by the regulator's output (though I do have some suspicious caps to
replace elsewhere).

William


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In article ,
who where wrote:

Murata now has some interesting little switching regulators which
"mimic" a 7805 - they have the same pinout, same current capacity, and
are built on a small PC board which is roughly the size and shape of a
TO-220.


Although I didn't say so explicitly, the two devices I mentioned are
also TO-220 "drop-in" switchers. It is certainly an emerging market
area.


The "Simple Switcher" (tm) parts I have seen up until now, have the
switcher controller, but you need to install external components
(inductor, etc.)., so their pinout isn't directly 7805-compatible.

The Murata parts have all of that on their own PCB - no additional
external components are required, if you can live with their output
levels.

I would expect to see other manufacturers come up with these sorts of
complete drop-in-ready modules.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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On Thu, 13 Oct 2011 09:03:39 -0700 (PDT), "William R. Walsh"
put finger to keyboard and composed:

But I would think that adding a bit of series
resistance to the input side and letting some of the waste
heat go away there would go a long way towards extending the
life of the regulator package.


I had not thought of this and might just sit down and do the math to
see what I'd need. What I do will depend upon whether or not there is
room to put something in place without going to extremes.


I agree that's the simplest solution. In fact I've done similar things
in lots of gear, including a 586 motherboard.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
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Hi!

These Murata parts are about $4.50 each in onesies, through Mouser.


If I've found the right part, I reckon you are speaking of the 7812SR/
SRH-C regulators. These look like interesting devices but the low
current rating may be a problem. I need to rig up a way to see what
the current draw actually is.

I don't think noise in the circuit would be a problem, this regulator
appears to be powering a protection circuit. I've not traced the
circuit to know exactly what it's powering beyond that.

William
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughtswanted...

Den 12-10-2011 19:05, William R. Walsh skrev:
Hello all...

This is part of a longer story which I won't get into now. Suffice it
to say that I've wanted to get my hands on a failed Sherwood RX-4105
or RX-4109 stereo receiver to see just what it is that kills
them...abuse, misuse, weak parts, bad engineering/quality control or
something else. I've never had any luck coming into a truly broken
one, but someone recently gave me an RX-5502 that would just shut down
right after power on. I've been very happy with all of the RX-4105 and
4109 units I own.

The RX-5502 is a so-called multi-zone receiver. That is to say it can
support up to eight connected pairs of speakers, with four of the
pairs playing a different ("room 2") source if that is desired. It has
two complete stereo amplifiers in place, each one claimed to have an
output power of 100 watts per channel. (Obviously they're dreaming if
they think that this receiver is ever going to output 400 total watts
of power without catching fire, but...) This example was manufactured
sometime in 2008.

As found, this set would indeed power on for a few seconds, and shut
down with a blinking standby LED. I started checking things out. In
this set, the amplifier board is separate from the main board, so this
was not terribly hard to do. Every power device tested good with a
simple ohmmeter check, and nothing looked burnt or distressed on the
amp board. This doesn't look like a case of a failed power transistor
to me.

I'm working without service literature or even a schematic as Sherwood
would not provide them, but there is printing on the board that
identifies what each conductor in the ribbon cable going to the amp
board is used for. This set has a "test mode", and unlike similar
models, the "test mode" allows the power to stay on indefinitely while
the display test is running. Testing for voltages is a lot nicer
without having to constantly turn the set back on again! Voltages are
what I'd expect for B+ and B-, but a twelve volt input to the board is
hovering around a few hundred millivolts at most. That could do it!

Removing the amplifier board from the system and running without it
was probably risky, but it seemed like a worthwhile thing to do. With
the amp board removed, there was still no voltage from the +12 volt
connection. It still hovered around 300mV with the set on.
Interestingly, every now and then, a good power up was possible with
the amp board out, and the set would come out of protection.
Okay...where is the +12 volt supply generated?

Over in the power supply section there are a few linear voltage
regulators--two heatsinked 7812s and one freestanding 7912. One 7812
and the 7912 are doing their jobs, but the other 7812 is cold to the
touch and does not seem to be doing anything. (In fact, it was putting
out 300mV when I later checked it.)

Replacing the failed 7812 with an LM340 solved the problem. The set
immediately came back to life with the amp board in place, and it
plays. It appears, based on simple observation, that one 7812 is
powering the coils leading up to the speaker selection/protection
relays and the other is powering the amp board itself. What other
loads might be powered by these regulators has not been determined.

While the set is working, I don't like the temperature at which the
new regulator is running. Within ten minutes, its heatsink is on the
verge of being too hot to touch for more than a few seconds. There is
evidence on the circuit board that these regulators have always run
very hot. I've been in touch with Sherwood America, who said "the
regulator may become too hot to touch and possibly fail". I strongly
suspect there are bad capacitors on the amp and main boards, which
will need to be replaced and may be stressing the regulator. Yet
Sherwood seems to be saying that the extremely hot operation is
*normal* here. (However, it should be said that there is something of
a language barrier with the folks I've been communicating with.)

I could install a fan above or larger heatsink on the regulator and
I'm not above doing it if that is just the way things will be. I
suspect that would force the regulator to operate more reliably.

What I really want to know, though, is whether or not a drop-in
replacement with more current delivering capability than the LM340 or
78xx series exists. I've looked halfheartedly over the years but never
found anything. I could always build a more capable regulator board
and hack it in there, but I don't really feel like doing that. A fan
would be easier and faster.

I'd also like to know if anyone has had an RX-5502 on their repair
bench, and if they could comment on just how hot its regulators were
running. Any thoughts would be very much appreciated!



Replace the burning hot 7812 with one of these:

http://www.dimensionengineering.com/...s/DE-SWADJ.pdf

I have no connection to the company only thinks their product is sweet.

--
Uffe Bærentsen
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

responding to
http://www.electrondepot.com/repair/...ug-134725-.htm
, T Wood wrote:
Thank you so much for the info. I found the 7812 that powered the amp to be
bad. A $2 radio shack part and a little time, and my RX-5502 is back up and
operational. Mine was shutting down exactly as you described and after
replacing the 7812, it has played music for over two hours and is still doing
great.



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You realize this is five years old and some of these people could be dead.

It might be nice to resurrect threads on websites that simply copy Usenet but have no content of their own, but to respond to it on Usenet is not nice. Some people get ****ed off.

Some people pull up **** from like 1991. this was even here in 1991 ? I mean, some cars still had carbs back then. They never heard of radon gas. Like a different world.


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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughtswanted...

On 2016-01-14, wrote:
You realize this is five years old and some of these people could be
dead.

It might be nice to resurrect threads on websites that simply copy
Usenet but have no content of their own, but to respond to it on
Usenet is not nice. Some people get ****ed off.


Threads about a fixing particular piece of consumer electronic equipment
tend to be old.

If someone has *new* information to add, like "I fixed a similar problem
with the same unit, and it went like this" it's perfectly fine;
there is nothing wrong with referencing the old thread.

Look, you're just not going to find a current, continuous, day-to-day
discussion thread on a darned Sherwood RX-5502, right?

But if you start trying to help that person from seven years ago by
asking questions, like "does the front panel light up, or is it
completely dead?" then you're indeed a necroposting moron who annoys
people, and probably shouldn't be using any device that has a CPU
and network connection.

Some people pull up **** from like 1991. this was even here in 1991 ?
I mean, some cars still had carbs back then. They never heard of radon
gas. Like a different world.


I'm pretty sure I heard of the issue of radon in homes in the middle
1980's. I'm in Canada, though; it's more of a problem in winterized
homes, whose residents don't open their damned windows for much of the
year.

Radon was already linked to lung cancer in non-smoking miners in the
1940's, according to https://en.wikipedia.org/wiki/Radon#Health_risks.
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughtswanted...

On Thu, 14 Jan 2016, Kaz Kylheku wrote:

On 2016-01-14, wrote:
You realize this is five years old and some of these people could be
dead.

It might be nice to resurrect threads on websites that simply copy
Usenet but have no content of their own, but to respond to it on
Usenet is not nice. Some people get ****ed off.


Threads about a fixing particular piece of consumer electronic equipment
tend to be old.

If someone has *new* information to add, like "I fixed a similar problem
with the same unit, and it went like this" it's perfectly fine;
there is nothing wrong with referencing the old thread.

No it's not fine.

This is not google, where the messages all appear. usenet was never
intended to be archived.

SOme idiot replying to an old thread isn't being part of the newsgroup,
they are simply doing google.

ANd whether or not that's good, the blunders pile on. They don't quote,
they don't acknowledge they are replying to an old message, they may not
even have a proper subject header (so instead of "" so we know it's a
reply, it can often look like the start of a thread. Without quoting,
there's no context, the only reason the post makes sense is because other
idiots before them have done the same thing, so it's most likely a google
idiot post.

The reality is people are replying to old threads for reasons that aren't
clear, but I suspect some of it is that they simply don't grasp where they
are, or that they are replying to an old thread.

And too often, someone replies to an old thread, and others jump in as if
the thread is new, because they are reading at google and the thread then
"comes to the top" and starts replying to the old thread. Too often,
those people haven't even read the old thread, so they are not adding
anything to it. Or, the person replying to the old thread gets replies,
again as if the thread is new. Often the old thread has covered the
problem, and anything new is just repetition. We had a resurrected thread
last year here, and it wasn't so old, so some of the original participants
replied, a second time, and gave about the same answer as they did the
first (and in that thread, the original poster had posted a followup, back
then, to reveal what solution had worked for them).


That's on top of the stupid posts where people ask a 1991 post "is this
thing still for sale?" or the like. Don't try to justify this based on a
specific newsgroup, the problem is that google still hasn't fixed the bug
that allows replies to messages older than 30 days.

You want everything neat and tidy in one place, but that doesn't happen.
And the same search that found the original thread should indeed find any
separate followup thread that someone posted much later.

Our place here isn't to deal with the future, at google, our place here is
an ongoing discussion of the repair of electronic equipment (or whatever
the newsgroup is intended for, if this was another newsgroup).

Look, you're just not going to find a current, continuous, day-to-day
discussion thread on a darned Sherwood RX-5502, right?

You're assuming that people only ask about current equipment.

I've read this newsgroup since late 1994, and when I got full internet
access in 1996, dejanews had already started archiving usenet posts. That
was neat, because every time I dragged home some neat piece of equipment
from a garage or rummage sale, I'd do a search, and often find some bit of
information about the new junk. If I'd needed to ask something, I'd not
reply to an old thread (and that option wasn't there with dejanews).

But if I'd wanted to ask about something I just dragged home, I'd post
away. And maybe someone would have information, maybe not, it depends on
who is reading the newsgroup.

Any of the idiots who keep replying to old threads is welcome to be a
member of this newsgroup, all they have to do is post a message, if they
want to talk about something old, that's okay too. Just don't reply to an
old message.


But if you start trying to help that person from seven years ago by
asking questions, like "does the front panel light up, or is it
completely dead?" then you're indeed a necroposting moron who annoys
people, and probably shouldn't be using any device that has a CPU
and network connection.

But when some idiot replies to an old post, here it's not so obvious
(except because there are telltales that we notice after the repeated
abuse), so others chime in to the old thread as if it is new. So whether
or not the first replier has some good thing to add, it's distruptive to
the newsgroup.

Forget about google, act here like this is Usenet, which it is. Messages
fade with time, unless someone saves them to their own hard drive. It's
nto intended to be a long term medium. So don't treat it like it is.

Anyone can post and say "there was a discussion ten years ago, and I
thought I'd add some more insight", they can even reference the old
message, or "I just got this new thing, so I thought I'd post some
comments about it". They don't need to rely on someone previously posting
about it.

Michael
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I don't know how you get here, but Google and aioe or whatever seem to be the only free ways to do it. Actually I probably should get a paid service but then, who gets that money ? Originally I got here via AOL but they stopped doing everything I wanted so I got rid of them.

Anyway, in Google the topics are arranged in reverse chronological order, sorted by most recent post. The date is right there, but it gives the latest date. So if it bugs you it bugs me more because I see on the right it says "4 hours ago", then I open it up and it does not skip the old posts because I have not read them through Google. Believe it or not I may have read or even be in some of these old posts. But that doesn't matter, most of my work was TVs so therefore it is all useless knowledge. Audio equipment is a different story. People are repairing and restoring old stuff every day, to the tune of mucho dinero I might add. One guy I did a job for in PA wound up with $600 into the repair. Half of that was the round trip on UPS, and they broke it ! I actually could have charged him more but I have him some money off because I put a scuff mark on the front panel. It is a Mitsubishi X-11 system with the vertical turntable. I had to fix the amp which meant retrofitting it to modern chips because the original is unobtanium, but before that I had to fix the power supply with a foil burnt off the board, which was quite worrisome at first. I had to fix a broken part in the cassette deck and put belts in that. Then when it got home, UPS somehow screwed up the TT tracking servo. I had to charge him another hundred for that but that included time and gas to meet him about halfway. We were not about to do UPS again. so about $700 for like a 25 watt per channel, magnetic cartridge (oh I replaced that also) and a pretty decent cassette deck. Although he'll never need outputs again, I used LM3886s.

At any rate, back to our regularly scheduled hijack, the people who respond to these old posts, like you said, must be finding them through a search. I mean a web search. for them to search SER, they would have to go to SER first, right ?

However, I just Googled for "Sherwood RX-5502" and no hits with "groups" on the first two pages. [

Then there is another thing, a bunch of websites archive Usenet and pretend they got a forum. Could they be finding these old posts that way ?

I mostly agree with you, but not with the preventing replies to posts over a month old. I think six months would be good. At least there's a good chance the people are still alive.
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

responding to
http://www.electrondepot.com/repair/...ug-134725-.htm
, T Wood wrote:

I just wanted to say thank you. I didn't realize that was so bad!!



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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

responding to
http://www.electrondepot.com/repair/...ug-134725-.htm
, T Wood wrote:
jurb6006 wrote:

I don't know how you get here, but Google and aioe or whatever seem to
be t
he only free ways to do it. Actually I probably should get a paid
service b
ut then, who gets that money ? Originally I got here via AOL but they
stopp
ed doing everything I wanted so I got rid of them.

Anyway, in Google the topics are arranged in reverse chronological
order, s
orted by most recent post. The date is right there, but it gives the
latest
date. So if it bugs you it bugs me more because I see on the right it
says
"4 hours ago", then I open it up and it does not skip the old
posts becaus
e I have not read them through Google. Believe it or not I may have read
or
even be in some of these old posts. But that doesn't matter, most of my
wo
rk was TVs so therefore it is all useless knowledge. Audio equipment is
a d
ifferent story. People are repairing and restoring old stuff every day,
to
the tune of mucho dinero I might add. One guy I did a job for in PA
wound u
p with $600 into the repair. Half of that was the round trip on UPS, and
th
ey broke it ! I actually could have charged him more but I have him some
mo
ney off because I put a scuff mark on the front panel. It is a
Mitsubishi X
-11 system with the vertical turntable. I had to fix the amp which meant
re
trofitting it to modern chips because the original is unobtanium, but
befor
e that I had to fix the power supply with a foil burnt off the board,
which
was quite worrisome at first. I had to fix a broken part in the
cassette d
eck and put belts in that. Then when it got home, UPS somehow screwed up
th
e TT tracking servo. I had to charge him another hundred for that but
that
included time and gas to meet him about halfway. We were not about to do
UP
S again. so about $700 for like a 25 watt per channel, magnetic
cartridge (
oh I replaced that also) and a pretty decent cassette deck. Although
he'll
never need outputs again, I used LM3886s.

At any rate, back to our regularly scheduled hijack, the people who
respond
to these old posts, like you said, must be finding them through a
search.
I mean a web search. for them to search SER, they would have to go to
SER f
irst, right ?

However, I just Googled for "Sherwood RX-5502" and no hits
with "groups" on
the first two pages. [

Then there is another thing, a bunch of websites archive Usenet and
pretend
they got a forum. Could they be finding these old posts that way ?

I mostly agree with you, but not with the preventing replies to posts
over
a month old. I think six months would be good. At least there's a good
chan
ce the people are still alive.

If you really care to know--I did a goggle search and found the info on
electrodepot.com. I replied through that web site. I have no idea what Usenet
is. I just know there is at least one ass that like calling people idiots


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T Wood wrote: "electrodepot.com. I replied through that web site. I have no idea what Usenet
is. I just know there is at least one ass that like calling people idiots "


Most folks born after 1980 wouldn't. Basically,
usenet WAS the internet. A worldwide "distributed
discussion system" according to Wikipedia:

https://en.m.wikipedia.org/wiki/Usenet

And many traditional Usenet users become very
irate and take it personal when someone - like
me - interacts with usenet groups via Google or
some other non-standard usenet interface.
What they see coming into the group from
a non-NNTP source is out of the ordinary that
the context of the message is lost.

But still, no reason for them to be jerks about it.
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

On Wednesday, January 13, 2016 at 11:37:04 PM UTC-5, T Wood wrote:
responding to
http://www.electrondepot.com/repair/...ug-134725-.htm
, T Wood wrote:
Thank you so much for the info. I found the 7812 that powered the amp to be
bad. A $2 radio shack part and a little time, and my RX-5502 is back up and
operational. Mine was shutting down exactly as you described and after
replacing the 7812, it has played music for over two hours and is still doing
great.


I have had the same problem with my RX-5502. Can you tell me what the $2 Radio Shack part is? I looked at the thread you quoted and did not see a reference to the part name or number. Thanks!
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

On Sunday, March 4, 2018 at 3:02:22 PM UTC-5, wrote:
On Wednesday, January 13, 2016 at 11:37:04 PM UTC-5, T Wood wrote:
responding to
http://www.electrondepot.com/repair/...ug-134725-.htm
, T Wood wrote:
Thank you so much for the info. I found the 7812 that powered the amp to be
bad. A $2 radio shack part and a little time, and my RX-5502 is back up and
operational. Mine was shutting down exactly as you described and after
replacing the 7812, it has played music for over two hours and is still doing
great.


I have had the same problem with my RX-5502. Can you tell me what the $2 Radio Shack part is? I looked at the thread you quoted and did not see a reference to the part name or number. Thanks!


Honestly, if "7812" and "regulator" don't ring any bells, you probably shouldn't be screwing around with this. It could not have been any more easy unless someone dispatches a courier to your home with one.

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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

On Sunday, 4 March 2018 20:02:22 UTC, wrote:
On Wednesday, January 13, 2016 at 11:37:04 PM UTC-5, T Wood wrote:
responding to
http://www.electrondepot.com/repair/...ug-134725-.htm
, T Wood wrote:
Thank you so much for the info. I found the 7812 that powered the amp to be
bad. A $2 radio shack part and a little time, and my RX-5502 is back up and
operational. Mine was shutting down exactly as you described and after
replacing the 7812, it has played music for over two hours and is still doing
great.


I have had the same problem with my RX-5502. Can you tell me what the $2 Radio Shack part is? I looked at the thread you quoted and did not see a reference to the part name or number. Thanks!


he told you, the 7812.


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On Sunday, March 4, 2018 at 6:02:16 PM UTC-5, wrote:
On Sunday, 4 March 2018 20:02:22 UTC, wrote:
On Wednesday, January 13, 2016 at 11:37:04 PM UTC-5, T Wood wrote:
responding to
http://www.electrondepot.com/repair/...ug-134725-.htm
, T Wood wrote:
Thank you so much for the info. I found the 7812 that powered the amp to be
bad. A $2 radio shack part and a little time, and my RX-5502 is back up and
operational. Mine was shutting down exactly as you described and after
replacing the 7812, it has played music for over two hours and is still doing
great.


I have had the same problem with my RX-5502. Can you tell me what the $2 Radio Shack part is? I looked at the thread you quoted and did not see a reference to the part name or number. Thanks!


he told you, the 7812.


Ah, yes. Sorry, for some reason I got it into my head that he replaced it with something different (and better). And to John-Del's point, I have no intention of getting in over my head with this; I am just mad that a product I paid a fair amount of money for stopped working after 4 hours of use. If I can find someone local to fix it, I will. Otherwise I'll move on with my life.
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What is local ? I fix these things.
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughtswanted...

On 3/6/18 12:16 AM, wrote:
In the end I was lucky to get about $2 an hour for my
time.


Not a very effective use of your time.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
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On Tuesday, 6 March 2018 06:32:03 UTC, Fox's Mercantile wrote:
On 3/6/18 12:16 AM, wrote:
In the end I was lucky to get about $2 an hour for my
time.


Not a very effective use of your time.


No, but we've all had jobs where that became true, more so when young.


NT
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