sci.electronics.repair@googlegroups.com

Today's topics:

* SMPS Clicking... - 9 messages, 8 authors
http://groups.google.com/group/sci.electronics.repair/t/b8d8ef25d8872acc?hl=en
* Tektronix TDS460 error logs - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/f25139bb0e0d91bd?hl=en
* iPod docks - 4 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/a8ed4f783a56727d?hl=en
* Marshall 6101 valve amp - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/5c8741aa70544d35?hl=en
* Lenovo N100 System Board Repair for a Battery Problem - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/2e8687210411a941?hl=en

==============================================================================
TOPIC: SMPS Clicking...
http://groups.google.com/group/sci.electronics.repair/t/b8d8ef25d8872acc?hl=en
==============================================================================

== 1 of 9 ==
Date: Wed, Oct 6 2010 10:55 pm
From: "Michael Kennedy"

Sorry if this is a bit of a novice question...

I have a SMPS in Plsama tv which upon powering up starts clicking... It
seems to do it as it warms up or the load changes on the psu (screen going
dark or getting light)

As far as I can tell it isnt any relay doing this, even though It sounds
like a relay.

Ticking alone I could live with, although a bit annoying but the PSU also
occasionally shuts down when cold. I am not 100% sure what is clicking.. The
clicking noise seems to be coming from different locations at dfferent
times, even possibly the X or Y sus boards.

I have sprayed the whole thing down with freeze spray to no avail... It is
built with PBF solder, so I guess bad solder joints are likely issue also.

I have changed the obvious capacitors near heat sources excpet the two large
400v 250uf filter caps.. Removed and checked the filter caps and they
checked good on my ESR meter.

Any Idea what would be clikcing? Here is the board layout
<https://sites.google.com/site/chibamikey/PSU.JPG>

== 2 of 9 ==
Date: Thurs, Oct 7 2010 5:04 am
From: "Mark Zacharias"

"Michael Kennedy" <mike@com> wrote in message
news:_PidnbvlitJd_TDRnZ2dnVY3gomdnZ2d@giganews.com...
> Sorry if this is a bit of a novice question...
>
> I have a SMPS in Plsama tv which upon powering up starts clicking... It
> seems to do it as it warms up or the load changes on the psu (screen going
> dark or getting light)
>
> As far as I can tell it isnt any relay doing this, even though It sounds
> like a relay.
>
> Ticking alone I could live with, although a bit annoying but the PSU also
> occasionally shuts down when cold. I am not 100% sure what is clicking..
> The clicking noise seems to be coming from different locations at dfferent
> times, even possibly the X or Y sus boards.
>
> I have sprayed the whole thing down with freeze spray to no avail... It is
> built with PBF solder, so I guess bad solder joints are likely issue also.
>
> I have changed the obvious capacitors near heat sources excpet the two
> large 400v 250uf filter caps.. Removed and checked the filter caps and
> they checked good on my ESR meter.
>
> Any Idea what would be clikcing? Here is the board layout
> <https://sites.google.com/site/chibamikey/PSU.JPG>
>
>

I have seen similar issues on Samsung plasmas resulting from bad solder
connections at some switching transistors near the middle of the board. The
eyelets are too small and need to be scraped a bit to enlarge them before
resoldering. The board does look similar to yours. Maybe you'll get lucky.
If not solder connections in there somewhere, failing capacitors would be
the likely culprit, although this problem has been much more common on LCD
sets. Plasmas I've seen don't seem to use the really cheap caps.

Mark Z.

== 3 of 9 ==
Date: Thurs, Oct 7 2010 7:49 am
From: "Michael Kennedy"

"Mark Zacharias" <mark_zacharias@sbcglobal.net> wrote in message
news:4cadb755$0$1752$c3e8da3$9f400e27@news.astraweb.com...
> "Michael Kennedy" <mike@com> wrote in message
> news:_PidnbvlitJd_TDRnZ2dnVY3gomdnZ2d@giganews.com...
>> Sorry if this is a bit of a novice question...
>>
>> I have a SMPS in Plsama tv which upon powering up starts clicking... It
>> seems to do it as it warms up or the load changes on the psu (screen
>> going dark or getting light)
>>
>> As far as I can tell it isnt any relay doing this, even though It sounds
>> like a relay.
>>
>> Ticking alone I could live with, although a bit annoying but the PSU also
>> occasionally shuts down when cold. I am not 100% sure what is clicking..
>> The clicking noise seems to be coming from different locations at
>> dfferent times, even possibly the X or Y sus boards.
>>
>> I have sprayed the whole thing down with freeze spray to no avail... It
>> is built with PBF solder, so I guess bad solder joints are likely issue
>> also.
>>
>> I have changed the obvious capacitors near heat sources excpet the two
>> large 400v 250uf filter caps.. Removed and checked the filter caps and
>> they checked good on my ESR meter.
>>
>> Any Idea what would be clikcing? Here is the board layout
>> <https://sites.google.com/site/chibamikey/PSU.JPG>
>>
>>
>
> I have seen similar issues on Samsung plasmas resulting from bad solder
> connections at some switching transistors near the middle of the board.
> The eyelets are too small and need to be scraped a bit to enlarge them
> before resoldering. The board does look similar to yours. Maybe you'll get
> lucky.
> If not solder connections in there somewhere, failing capacitors would be
> the likely culprit, although this problem has been much more common on LCD
> sets. Plasmas I've seen don't seem to use the really cheap caps.
>
> Mark Z.

Thanks you suggested that before.. I will get a closer look at the
transistors and check out those eyelits.. I havent doent that yet, and
probably would have forgot had you not replied.

About the ticking.. It doesn't stop even with the power removed. It is
almost if something is expanding and contracting, but makes the sound
equilivant of a relay?!

The really strange part is it doesn't seem to come from one consistant
place.. :(

== 4 of 9 ==
Date: Thurs, Oct 7 2010 10:28 am
From: PlainBill47@yawho.com

On Thu, 7 Oct 2010 23:49:25 +0900, "Michael Kennedy" <mike@nospam.com>
wrote:

>
>"Mark Zacharias" <mark_zacharias@sbcglobal.net> wrote in message
>news:4cadb755$0$1752$c3e8da3$9f400e27@news.astraweb.com...
>> "Michael Kennedy" <mike@com> wrote in message
>> news:_PidnbvlitJd_TDRnZ2dnVY3gomdnZ2d@giganews.com...
>>> Sorry if this is a bit of a novice question...
>>>
>>> I have a SMPS in Plsama tv which upon powering up starts clicking... It
>>> seems to do it as it warms up or the load changes on the psu (screen
>>> going dark or getting light)
>>>
>>> As far as I can tell it isnt any relay doing this, even though It sounds
>>> like a relay.
>>>
>>> Ticking alone I could live with, although a bit annoying but the PSU also
>>> occasionally shuts down when cold. I am not 100% sure what is clicking..
>>> The clicking noise seems to be coming from different locations at
>>> dfferent times, even possibly the X or Y sus boards.
>>>
>>> I have sprayed the whole thing down with freeze spray to no avail... It
>>> is built with PBF solder, so I guess bad solder joints are likely issue
>>> also.
>>>
>>> I have changed the obvious capacitors near heat sources excpet the two
>>> large 400v 250uf filter caps.. Removed and checked the filter caps and
>>> they checked good on my ESR meter.
>>>
>>> Any Idea what would be clikcing? Here is the board layout
>>> <https://sites.google.com/site/chibamikey/PSU.JPG>
>>>
>>>
>>
>> I have seen similar issues on Samsung plasmas resulting from bad solder
>> connections at some switching transistors near the middle of the board.
>> The eyelets are too small and need to be scraped a bit to enlarge them
>> before resoldering. The board does look similar to yours. Maybe you'll get
>> lucky.
>> If not solder connections in there somewhere, failing capacitors would be
>> the likely culprit, although this problem has been much more common on LCD
>> sets. Plasmas I've seen don't seem to use the really cheap caps.
>>
>> Mark Z.
>
>
>Thanks you suggested that before.. I will get a closer look at the
>transistors and check out those eyelits.. I havent doent that yet, and
>probably would have forgot had you not replied.
>
>
>
>About the ticking.. It doesn't stop even with the power removed. It is
>almost if something is expanding and contracting, but makes the sound
>equilivant of a relay?!
>
>The really strange part is it doesn't seem to come from one consistant
>place.. :(
>
Power removed or TV turned off? If it continues long after the set is
turned off (but still connected to AC power) it is something in the
standby power section of the main power supply.

If it continues for hours after the set is unplugged, it's probably a
cricket.

PlainBill

== 5 of 9 ==
Date: Thurs, Oct 7 2010 12:50 pm
From: jeanyves

On 2010-10-07 07:55:49 +0200, "Michael Kennedy" <mike@com> said:

> Sorry if this is a bit of a novice question...
>
> I have a SMPS in Plsama tv which upon powering up starts clicking...
> It seems to do it as it warms up or the load changes on the psu (screen
> going dark or getting light)
>
> As far as I can tell it isnt any relay doing this, even though It
> sounds like a relay.
>
> Ticking alone I could live with, although a bit annoying but the PSU
> also occasionally shuts down when cold. I am not 100% sure what is
> clicking.. The clicking noise seems to be coming from different
> locations at dfferent times, even possibly the X or Y sus boards.
>
> I have sprayed the whole thing down with freeze spray to no avail... It
> is built with PBF solder, so I guess bad solder joints are likely issue
> also.
>
> I have changed the obvious capacitors near heat sources excpet the two
> large 400v 250uf filter caps.. Removed and checked the filter caps and
> they checked good on my ESR meter.
>
> Any Idea what would be clikcing? Here is the board layout
> <https://sites.google.com/site/chibamikey/PSU.JPG>

I would change the main 400v capacitor
clicks means this capacitor is almost dry ...
regards,
--
-
Jean-Yves

== 6 of 9 ==
Date: Thurs, Oct 7 2010 5:45 pm
From: "circuit"

Its got to stop sometime after its been unplugged. I do not think there are
any relays in todays plasma power boards, so the ticking is likely coming
from a transformer. Its a ' special effect ' that happens when the power
supply is loaded down somewhere, usually on one of the main DC outputs. The
overload condition triggers an imbalance in the feedback circuirty, and the
power supply cannot sustain itself with this condition present. You may want
to check the temperature of the big heat sinks on the X-sus board at the
peak of the problem, could be they are very hot.

> About the ticking.. It doesn't stop even with the power removed. It is
> almost if something is expanding and contracting, but makes the sound
> equilivant of a relay?!
>
> The really strange part is it doesn't seem to come from one consistant
> place.. :(
>

== 7 of 9 ==
Date: Thurs, Oct 7 2010 5:52 pm
From: "Michael Kennedy"

<PlainBill47@yawho.com> wrote in message
news:5f0sa6dr1m0falp5kdhcmvc2mdhj30iqtr@4ax.com...
> On Thu, 7 Oct 2010 23:49:25 +0900, "Michael Kennedy" <mike@nospam.com>
> wrote:
>
>>
>>"Mark Zacharias" <mark_zacharias@sbcglobal.net> wrote in message
>>news:4cadb755$0$1752$c3e8da3$9f400e27@news.astraweb.com...
>>> "Michael Kennedy" <mike@com> wrote in message
>>> news:_PidnbvlitJd_TDRnZ2dnVY3gomdnZ2d@giganews.com...
>>>> Sorry if this is a bit of a novice question...
>>>>
>>>> I have a SMPS in Plsama tv which upon powering up starts clicking...
>>>> It
>>>> seems to do it as it warms up or the load changes on the psu (screen
>>>> going dark or getting light)
>>>>
>>>> As far as I can tell it isnt any relay doing this, even though It
>>>> sounds
>>>> like a relay.
>>>>
>>>> Ticking alone I could live with, although a bit annoying but the PSU
>>>> also
>>>> occasionally shuts down when cold. I am not 100% sure what is
>>>> clicking..
>>>> The clicking noise seems to be coming from different locations at
>>>> dfferent times, even possibly the X or Y sus boards.
>>>>
>>>> I have sprayed the whole thing down with freeze spray to no avail... It
>>>> is built with PBF solder, so I guess bad solder joints are likely issue
>>>> also.
>>>>
>>>> I have changed the obvious capacitors near heat sources excpet the two
>>>> large 400v 250uf filter caps.. Removed and checked the filter caps and
>>>> they checked good on my ESR meter.
>>>>
>>>> Any Idea what would be clikcing? Here is the board layout
>>>> <https://sites.google.com/site/chibamikey/PSU.JPG>
>>>>
>>>>
>>>
>>> I have seen similar issues on Samsung plasmas resulting from bad solder
>>> connections at some switching transistors near the middle of the board.
>>> The eyelets are too small and need to be scraped a bit to enlarge them
>>> before resoldering. The board does look similar to yours. Maybe you'll
>>> get
>>> lucky.
>>> If not solder connections in there somewhere, failing capacitors would
>>> be
>>> the likely culprit, although this problem has been much more common on
>>> LCD
>>> sets. Plasmas I've seen don't seem to use the really cheap caps.
>>>
>>> Mark Z.
>>
>>
>>Thanks you suggested that before.. I will get a closer look at the
>>transistors and check out those eyelits.. I havent doent that yet, and
>>probably would have forgot had you not replied.
>>
>>
>>
>>About the ticking.. It doesn't stop even with the power removed. It is
>>almost if something is expanding and contracting, but makes the sound
>>equilivant of a relay?!
>>
>>The really strange part is it doesn't seem to come from one consistant
>>place.. :(
>>
> Power removed or TV turned off? If it continues long after the set is
> turned off (but still connected to AC power) it is something in the
> standby power section of the main power supply.
>
> If it continues for hours after the set is unplugged, it's probably a
> cricket.
>
> PlainBill

No its not hours, but at least 3 or 4 minutes.. Sounds like a realy clicking
sometimes.. Other times not so loud.. Makes me think of expanding and
contracting metal, although I cant see how that is possible given the low
tempatures.

== 8 of 9 ==
Date: Thurs, Oct 7 2010 6:31 pm
From: "Brenda Ann"

"Michael Kennedy" <mike@com> wrote in message
news:xbidnZTf8NMI8zPRnZ2dnVY3goqdnZ2d@giganews.com...
>
> <PlainBill47@yawho.com> wrote in message
> news:5f0sa6dr1m0falp5kdhcmvc2mdhj30iqtr@4ax.com...
>> On Thu, 7 Oct 2010 23:49:25 +0900, "Michael Kennedy" <mike@nospam.com>
>> wrote:
>>
>>>
>>>"Mark Zacharias" <mark_zacharias@sbcglobal.net> wrote in message
>>>news:4cadb755$0$1752$c3e8da3$9f400e27@news.astraweb.com...
>>>> "Michael Kennedy" <mike@com> wrote in message
>>>> news:_PidnbvlitJd_TDRnZ2dnVY3gomdnZ2d@giganews.com...
>>>>> Sorry if this is a bit of a novice question...
>>>>>
>>>>> I have a SMPS in Plsama tv which upon powering up starts clicking...
>>>>> It
>>>>> seems to do it as it warms up or the load changes on the psu (screen
>>>>> going dark or getting light)
>>>>>
>>>>> As far as I can tell it isnt any relay doing this, even though It
>>>>> sounds
>>>>> like a relay.
>>>>>
>>>>> Ticking alone I could live with, although a bit annoying but the PSU
>>>>> also
>>>>> occasionally shuts down when cold. I am not 100% sure what is
>>>>> clicking..
>>>>> The clicking noise seems to be coming from different locations at
>>>>> dfferent times, even possibly the X or Y sus boards.
>>>>>
>>>>> I have sprayed the whole thing down with freeze spray to no avail...
>>>>> It
>>>>> is built with PBF solder, so I guess bad solder joints are likely
>>>>> issue
>>>>> also.
>>>>>
>>>>> I have changed the obvious capacitors near heat sources excpet the two
>>>>> large 400v 250uf filter caps.. Removed and checked the filter caps and
>>>>> they checked good on my ESR meter.
>>>>>
>>>>> Any Idea what would be clikcing? Here is the board layout
>>>>> <https://sites.google.com/site/chibamikey/PSU.JPG>
>>>>>
>>>>>
>>>>
>>>> I have seen similar issues on Samsung plasmas resulting from bad solder
>>>> connections at some switching transistors near the middle of the board.
>>>> The eyelets are too small and need to be scraped a bit to enlarge them
>>>> before resoldering. The board does look similar to yours. Maybe you'll
>>>> get
>>>> lucky.
>>>> If not solder connections in there somewhere, failing capacitors would
>>>> be
>>>> the likely culprit, although this problem has been much more common on
>>>> LCD
>>>> sets. Plasmas I've seen don't seem to use the really cheap caps.
>>>>
>>>> Mark Z.
>>>
>>>
>>>Thanks you suggested that before.. I will get a closer look at the
>>>transistors and check out those eyelits.. I havent doent that yet, and
>>>probably would have forgot had you not replied.
>>>
>>>
>>>
>>>About the ticking.. It doesn't stop even with the power removed. It is
>>>almost if something is expanding and contracting, but makes the sound
>>>equilivant of a relay?!
>>>
>>>The really strange part is it doesn't seem to come from one consistant
>>>place.. :(
>>>
>> Power removed or TV turned off? If it continues long after the set is
>> turned off (but still connected to AC power) it is something in the
>> standby power section of the main power supply.
>>
>> If it continues for hours after the set is unplugged, it's probably a
>> cricket.
>>
>> PlainBill
>
>
> No its not hours, but at least 3 or 4 minutes.. Sounds like a realy
> clicking sometimes.. Other times not so loud.. Makes me think of expanding
> and contracting metal, although I cant see how that is possible given the
> low tempatures.

Hope it isn't the PDP. I've read horror stories about those expanding and
contracting (they do get VERY hot), and finally cracking.

>

== 9 of 9 ==
Date: Fri, Oct 8 2010 12:43 am
From: "N_Cook"

<PlainBill47@yawho.com> wrote in message
news:5f0sa6dr1m0falp5kdhcmvc2mdhj30iqtr@4ax.com...
> On Thu, 7 Oct 2010 23:49:25 +0900, "Michael Kennedy" <mike@nospam.com>
> wrote:
>
> >
> >"Mark Zacharias" <mark_zacharias@sbcglobal.net> wrote in message
> >news:4cadb755$0$1752$c3e8da3$9f400e27@news.astraweb.com...
> >> "Michael Kennedy" <mike@com> wrote in message
> >> news:_PidnbvlitJd_TDRnZ2dnVY3gomdnZ2d@giganews.com...
> >>> Sorry if this is a bit of a novice question...
> >>>
> >>> I have a SMPS in Plsama tv which upon powering up starts clicking...
It
> >>> seems to do it as it warms up or the load changes on the psu (screen
> >>> going dark or getting light)
> >>>
> >>> As far as I can tell it isnt any relay doing this, even though It
sounds
> >>> like a relay.
> >>>
> >>> Ticking alone I could live with, although a bit annoying but the PSU
also
> >>> occasionally shuts down when cold. I am not 100% sure what is
clicking..
> >>> The clicking noise seems to be coming from different locations at
> >>> dfferent times, even possibly the X or Y sus boards.
> >>>
> >>> I have sprayed the whole thing down with freeze spray to no avail...
It
> >>> is built with PBF solder, so I guess bad solder joints are likely
issue
> >>> also.
> >>>
> >>> I have changed the obvious capacitors near heat sources excpet the two
> >>> large 400v 250uf filter caps.. Removed and checked the filter caps and
> >>> they checked good on my ESR meter.
> >>>
> >>> Any Idea what would be clikcing? Here is the board layout
> >>> <https://sites.google.com/site/chibamikey/PSU.JPG>
> >>>
> >>>
> >>
> >> I have seen similar issues on Samsung plasmas resulting from bad solder
> >> connections at some switching transistors near the middle of the board.
> >> The eyelets are too small and need to be scraped a bit to enlarge them
> >> before resoldering. The board does look similar to yours. Maybe you'll
get
> >> lucky.
> >> If not solder connections in there somewhere, failing capacitors would
be
> >> the likely culprit, although this problem has been much more common on
LCD
> >> sets. Plasmas I've seen don't seem to use the really cheap caps.
> >>
> >> Mark Z.
> >
> >
> >Thanks you suggested that before.. I will get a closer look at the
> >transistors and check out those eyelits.. I havent doent that yet, and
> >probably would have forgot had you not replied.
> >
> >
> >
> >About the ticking.. It doesn't stop even with the power removed. It is
> >almost if something is expanding and contracting, but makes the sound
> >equilivant of a relay?!
> >
> >The really strange part is it doesn't seem to come from one consistant
> >place..

> >
> Power removed or TV turned off? If it continues long after the set is
> turned off (but still connected to AC power) it is something in the
> standby power section of the main power supply.
>
> If it continues for hours after the set is unplugged, it's probably a
> cricket.
>
> PlainBill

In the UK there is some bug that clicks , regular clicks when active, but
not continuously, comes and goes at random. If , when it is in tapping mood,
you tap near wherever it is hiding, it stops abrubtly, presumably thinking
its found a mate. Not death-watch beatle as not in timber

==============================================================================
TOPIC: Tektronix TDS460 error logs
http://groups.google.com/group/sci.electronics.repair/t/f25139bb0e0d91bd?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 7 2010 1:59 am
From: JW

On Wed, 06 Oct 2010 19:28:19 +0200 Reinhard Zwirner
<reinhard_zwirner@web.de> wrote in Message id:
<4CACB1B3.DC161E15@t-online.de>:

>JW schrieb:
>>
>> Just finished repairing a TDS460, and I'm trying to clear the error logs.
>> Sending ERR CLE or ERROR CLEAR via the GPIB, which works on the TDS5XX and
>> up scopes does not seem to work on the TDS4XX scopes. Wondering if anyone
>> knows how to clear the logs or what GPIB command is used? There's nothing
>> in the service or programmers manual about this.
>>
>> Thanks.
>
>Ask here:
>
><http://tech.groups.yahoo.com/group/TekScopes/?yguid=190459268>
>
>HTH

Thanks Reinhard, but already been there - I've been an active member there
for a few years. Anyway, since I wasn't able to clear the error log via
GPIB, I disconnected the battery for a minute while the power was off. On
the first power up there was one power up failure on Dsp, and in the error
logs all of the previous errors were gone. On subsequent power ups, all is
well, except for the two errors that were generated from the loss of
Vbat. (NVRAM and Pudiag failure.)

I tried to set the dip switch 3 off hoping like the TDS5XX scopes that it
would skip these tests, but that didn't work either. Oh well, I guess I
can live with just the two errors :)

==============================================================================
TOPIC: iPod docks
http://groups.google.com/group/sci.electronics.repair/t/a8ed4f783a56727d?hl=en
==============================================================================

== 1 of 4 ==
Date: Thurs, Oct 7 2010 2:00 am
From: JW

On Thu, 07 Oct 2010 01:51:18 -0400 "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote in Message id:
<a7udnQxobItCwjDRnZ2dnUVZ_o2dnZ2d@earthlink.com>:

>
>D Yuniskis wrote:
>>
>> Hi Neil,
>>
>> nesesu wrote:
>> > On Sep 29, 2:54 pm, D Yuniskis <not.going.to...@seen.com> wrote:
>> >
>> >> I come across a fair number of "defective" iPod "stereos"
>> >> (countertop boxes into which an iPod is docked). Is there
>> >> something intrinsically bad with these (besides being
>> >> crappy consumer kit) that drives these failures?
>> >>
>> >> (e.g., the docking and undocking of the iPod without, perhaps,
>> >> adequate protection on the interconnect signals)
>> >
>> > Well, if it is like many cordless phones, placing the handset onto the
>> > base while carrying a large static charge will scramble the base
>> > operation. On mine I need to unplug the wall wart from the base unit
>> > to restore operation. Unfortunately, the base always faults to the OFF-
>> > LINE state and puts a high level of receiver noise on the line and the
>> > only indication that it is not working is a). no calls received and b)
>> > picking up a wired phone greets you with the high level noise.
>> > I have repaired lots of equipment that has no factory installed ESD
>> > protection on the user interface and usually has a damaged interface
>> > chip or device. Most of these devices were industrial and the designer
>> > should have known better.
>>
>> Most of these devices seem to have "sticky" (persistent) failures
>> when I encounter them. I.e., it is not a transient issue associated
>> with some action on my part.
>>
>> For example, I have a unit, now, that runs well for "some amount of
>> time" and then *appears* to keep running -- though any attempts to
>> interact with it (the "dock") are ignored. E.g., withOUT an iPod
>> docked into it, I can select the "RADIO" funtion, tune a station
>> using the up/down buttons, adjust the volume, etc. The radio
>> will play as expected. Some time later, an attempt to alter the
>> volume or change the station will be totally ignored. Or, the
>> device might power itself *off* unprovoked.
>>
>> I.e., it is as if the processor in the thing has crashed and:
>> - left things "as is" (in the case where the radio keeps playing
>> but buttons are ignored)
>> or
>> - crashed and "reset" all the I/O to "off" in the process.
>>
>> Behaviors on other devices have been similar. It is as if
>> ESD has toasted something internally so that it only marginally
>> works -- or works temporarily.
>>
>> <shrug> Most of these aren't worth the time to fix. I was
>> just curious as to why so man of them -- different models,
>> different manufacturers, etc. -- were exhibiting the same
>> sorts of general failures.
>
>
> Lead free solder.

+ Chinese manufacturing.

== 2 of 4 ==
Date: Thurs, Oct 7 2010 3:32 am
From: "Michael A. Terrell"

JW wrote:
>
> On Thu, 07 Oct 2010 01:51:18 -0400 "Michael A. Terrell"
> <mike.terrell@earthlink.net> wrote in Message id:
> <a7udnQxobItCwjDRnZ2dnUVZ_o2dnZ2d@earthlink.com>:
>
> >
> >D Yuniskis wrote:
> >>
> >> Hi Neil,
> >>
> >> nesesu wrote:
> >> > On Sep 29, 2:54 pm, D Yuniskis <not.going.to...@seen.com> wrote:
> >> >
> >> >> I come across a fair number of "defective" iPod "stereos"
> >> >> (countertop boxes into which an iPod is docked). Is there
> >> >> something intrinsically bad with these (besides being
> >> >> crappy consumer kit) that drives these failures?
> >> >>
> >> >> (e.g., the docking and undocking of the iPod without, perhaps,
> >> >> adequate protection on the interconnect signals)
> >> >
> >> > Well, if it is like many cordless phones, placing the handset onto the
> >> > base while carrying a large static charge will scramble the base
> >> > operation. On mine I need to unplug the wall wart from the base unit
> >> > to restore operation. Unfortunately, the base always faults to the OFF-
> >> > LINE state and puts a high level of receiver noise on the line and the
> >> > only indication that it is not working is a). no calls received and b)
> >> > picking up a wired phone greets you with the high level noise.
> >> > I have repaired lots of equipment that has no factory installed ESD
> >> > protection on the user interface and usually has a damaged interface
> >> > chip or device. Most of these devices were industrial and the designer
> >> > should have known better.
> >>
> >> Most of these devices seem to have "sticky" (persistent) failures
> >> when I encounter them. I.e., it is not a transient issue associated
> >> with some action on my part.
> >>
> >> For example, I have a unit, now, that runs well for "some amount of
> >> time" and then *appears* to keep running -- though any attempts to
> >> interact with it (the "dock") are ignored. E.g., withOUT an iPod
> >> docked into it, I can select the "RADIO" funtion, tune a station
> >> using the up/down buttons, adjust the volume, etc. The radio
> >> will play as expected. Some time later, an attempt to alter the
> >> volume or change the station will be totally ignored. Or, the
> >> device might power itself *off* unprovoked.
> >>
> >> I.e., it is as if the processor in the thing has crashed and:
> >> - left things "as is" (in the case where the radio keeps playing
> >> but buttons are ignored)
> >> or
> >> - crashed and "reset" all the I/O to "off" in the process.
> >>
> >> Behaviors on other devices have been similar. It is as if
> >> ESD has toasted something internally so that it only marginally
> >> works -- or works temporarily.
> >>
> >> <shrug> Most of these aren't worth the time to fix. I was
> >> just curious as to why so man of them -- different models,
> >> different manufacturers, etc. -- were exhibiting the same
> >> sorts of general failures.
> >
> >
> > Lead free solder.
>
> + Chinese manufacturing.

= Cheap, throwaway crap.

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

== 3 of 4 ==
Date: Thurs, Oct 7 2010 3:42 am
From: JW

On Thu, 07 Oct 2010 06:32:30 -0400 "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote in Message id:
<2OCdnZGA_cpVPDDRnZ2dnUVZ_s2dnZ2d@earthlink.com>:

>
>JW wrote:
>>
>> On Thu, 07 Oct 2010 01:51:18 -0400 "Michael A. Terrell"
>> <mike.terrell@earthlink.net> wrote in Message id:
>> <a7udnQxobItCwjDRnZ2dnUVZ_o2dnZ2d@earthlink.com>:
>>
>> >
>> >D Yuniskis wrote:
>> >>
>> >> Hi Neil,
>> >>
>> >> nesesu wrote:
>> >> > On Sep 29, 2:54 pm, D Yuniskis <not.going.to...@seen.com> wrote:
>> >> >
>> >> >> I come across a fair number of "defective" iPod "stereos"
>> >> >> (countertop boxes into which an iPod is docked). Is there
>> >> >> something intrinsically bad with these (besides being
>> >> >> crappy consumer kit) that drives these failures?
>> >> >>
>> >> >> (e.g., the docking and undocking of the iPod without, perhaps,
>> >> >> adequate protection on the interconnect signals)
>> >> >
>> >> > Well, if it is like many cordless phones, placing the handset onto the
>> >> > base while carrying a large static charge will scramble the base
>> >> > operation. On mine I need to unplug the wall wart from the base unit
>> >> > to restore operation. Unfortunately, the base always faults to the OFF-
>> >> > LINE state and puts a high level of receiver noise on the line and the
>> >> > only indication that it is not working is a). no calls received and b)
>> >> > picking up a wired phone greets you with the high level noise.
>> >> > I have repaired lots of equipment that has no factory installed ESD
>> >> > protection on the user interface and usually has a damaged interface
>> >> > chip or device. Most of these devices were industrial and the designer
>> >> > should have known better.
>> >>
>> >> Most of these devices seem to have "sticky" (persistent) failures
>> >> when I encounter them. I.e., it is not a transient issue associated
>> >> with some action on my part.
>> >>
>> >> For example, I have a unit, now, that runs well for "some amount of
>> >> time" and then *appears* to keep running -- though any attempts to
>> >> interact with it (the "dock") are ignored. E.g., withOUT an iPod
>> >> docked into it, I can select the "RADIO" funtion, tune a station
>> >> using the up/down buttons, adjust the volume, etc. The radio
>> >> will play as expected. Some time later, an attempt to alter the
>> >> volume or change the station will be totally ignored. Or, the
>> >> device might power itself *off* unprovoked.
>> >>
>> >> I.e., it is as if the processor in the thing has crashed and:
>> >> - left things "as is" (in the case where the radio keeps playing
>> >> but buttons are ignored)
>> >> or
>> >> - crashed and "reset" all the I/O to "off" in the process.
>> >>
>> >> Behaviors on other devices have been similar. It is as if
>> >> ESD has toasted something internally so that it only marginally
>> >> works -- or works temporarily.
>> >>
>> >> <shrug> Most of these aren't worth the time to fix. I was
>> >> just curious as to why so man of them -- different models,
>> >> different manufacturers, etc. -- were exhibiting the same
>> >> sorts of general failures.
>> >
>> >
>> > Lead free solder.
>>
>> + Chinese manufacturing.
>
>
> = Cheap, throwaway crap.

* Wasted money.

== 4 of 4 ==
Date: Thurs, Oct 7 2010 9:03 am
From: "Michael A. Terrell"

JW wrote:
>
> Michael A. Terrell wrote:
> >
> >JW wrote:
> >>
> >> Michael A. Terrell wrote:
> >> >
> >> > Lead free solder.
> >>
> >> + Chinese manufacturing.
> >
> > = Cheap, throwaway crap.
>
> * Wasted money.

* Cheapskates don't care. All they care is that it's
CHEEEEEEEEEEEEEP!!! :(

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

==============================================================================
TOPIC: Marshall 6101 valve amp
http://groups.google.com/group/sci.electronics.repair/t/5c8741aa70544d35?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 7 2010 4:15 am
From: "N_Cook"

Gareth Magennis <sound.service@btconnect.com> wrote in message
news:ZY4ro.48042$Wp7.30844@newsfe24.ams2...
>
>
> "N_Cook" <diverse@tcp.co.uk> wrote in message
> news:i8erk0$954$1@news.eternal-september.org...
> > dkxl5 <dkxl5_at_cox_dot_net@foo.com> wrote in message
> > news:2a1df$4caa73e6$43de0cc0$27308@news.flashnewsgroups.com...
> >> dkxl5 had written this in response to
> >>
http://www.electrondepot.com/repair/Re-Marshall-6101-valve-amp-35906-.htm
> >> :
> >>
> >> N_Cook wrote:
> >>
> >>
> >>
> >>
> >>
> >> -------------------------------------
> >> dkxl5
> >>
> >> The mute button between the pwr amp send/return jacks does not have any
> >> indicator that I'm aware of.
> >> The channel leds can be finicky sometimes. Sometimes when I turn mine
on
> >> all 3 leds come on and a quick
> >> on/off of the power switch snaps it back to the proper channel led.
> >> There
> >> are some awkward quirks with
> >> the amp. Make sure the mute switch is not engaged. If the series loop
> >> button is engaged you will not get
> >> any sound from the amp, though the effects knob will vary the loop send
> >> output and you can still send a
> >> signal into the return and hear it in the speaker. When switched to
> >> parallel you will have sound through
> >> the amp from the input.
> >>
> >>
> >> ##-----------------------------------------------##
> >> Delivered via http://www.electrondepot.com/
> >> Electronics Enthusiasts' Community of the Net
> >> Web and RSS access to your favorite newsgroup -
> >> sci.electronics.repair - 35126 messages and counting!
> >> ##-----------------------------------------------##
> >
> >
> > I'm wondering if the 3 LED lit thing is only at power up, I remember
from
> > the other one it also locks out ch selection and maybe use at all via
the
> > front input until de-muted. But maybe it was like your observation, poor
> > initialisation.reset at power up
> >
> >
>
> Bad Low voltage power supply (V mute switching).
>
> Bad FET or switch.
>
> Dry joint.
>
> Definitely nothing to do with initialisation.
>
>
>
> My guess is FET.
>
>
>
>
>
>
>
>
>
>
>

Amp not open at the moment, looking at schema if SW301 is the mute switch
then no logic connection to the 8031A / LEDs. The ch sw lines go through the
8031A to the HC574 to the LEDs so I suspect electro C301 of the p9 reset for
random power-up problems

==============================================================================
TOPIC: Lenovo N100 System Board Repair for a Battery Problem
http://groups.google.com/group/sci.electronics.repair/t/2e8687210411a941?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 7 2010 10:37 am
From: "behindontaxes@xemaps.com"

PeterD <peter2@hipson.net> wrote in
news:nli9q5duce8v0nmqcmbum26uqekjrru4gh@4ax.com:

> On Fri, 19 Mar 2010 17:12:20 -0500, "behindontaxes@xemaps.com"
> <behindontaxes@xemaps.com> wrote:
>
>>I received one with a wiped hard drive and 1 GB of RAM. The
>>battery would charge for a few seconds and then the battery icon
>>would turn off. The N100 would not turn on without a connected AC
>>adapter. This battery has 85% charge according to Windows 7, but
>>the laptop is not charging the battery. After a few sessions using
>>this battery for e- mail and web-surfing, the laptop would abruptly
>>turn off, as if all power got cut off to the laptop. Turning it
>>on again (with battery and AC adapter connected) would replicate the
>>behavior after a few minutes of usage. I was also able to
>>replicate this behavior without loading Windows (7) - I navigated
>>through the BIOS setup when I replicated the condition.
>>
>>I'm able to change the behavior by removing the battery and only
>>using the AC adapter.
>>
>>I bought another battery with the same FRU/ASM P/N with the same
>>amount of charge and was able to replicate the condition.
>>
>>I bought yet another battery with a DIFFERENT FRU/ASM P/N. This
>>battery had a minimal amount of charge. Attempting to turn it out
>>generated the battery icon LED, telling me there's not enough charge
>>to turn on the laptop. After a few seconds of charging, the
>>battery icon also turned off. While I haven't loaded WIndows with
>>this battery, I suspect it will also fail to charge and abruptly
>>shut off.
>>
>>I'm at a point where I can now say the system board is defective.
>>I'm aware of the program that replaced certain N100 batteries and
>>I'm aware this program has expired. I can't update the BIOS
>>because WinFlash works only in a 32-bit operating system (according
>>to the TXT file), and my Windows 7 is 64-bit.
>>
>>I have considered replacing the system board, but would much rather
>>repair it with a soldering iron. The risk to me is minimal, as I
>>received the laptop in a barebones state at no cost. I'm presuming
>>the battery connector is attached to the system board, and no stand
>>alone battery connector exists for the N100.
>>
>>I'd love to hear from anyone who's attempted to repair power
>>problems on this laptop with a soldering iron.
>>
>>Thanks for reading.
>
> Are you 100% sure you are using the right A/C adapter-charger?
>

The AC adapter is genuine Lenovo and is rated for the exact number of
volts and amps. If I get my hands on another one, I'll try it with
THAT adapter. I honestly anticipate the same results.

==============================================================================

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