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 Marshall AS100D, of 2008

No output unless in echo effects mode. Owner put away for 2 years. Covered
in PbF & Rohs stickers.
Now I find no problem . Send/Return/footsw sockets are not active bypass
configuration. Anti-feedback on/off switch is iffy but I doubt would kill
throughput .
Any known URL for a schematic out there?
Then how to reassemble the 4-off speaker wire routing, rod fed thru pcb hole
and chassis hole and load a speaker crimp connector on the end of the rod to
pull back through, crossing fingers that it will not dislodge? I'm not
skilled in chopstick use.




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Default Marshall AS100D, of 2008



"N_Cook" wrote in message
...
No output unless in echo effects mode. Owner put away for 2 years. Covered
in PbF & Rohs stickers.
Now I find no problem . Send/Return/footsw sockets are not active bypass
configuration. Anti-feedback on/off switch is iffy but I doubt would kill
throughput .
Any known URL for a schematic out there?
Then how to reassemble the 4-off speaker wire routing, rod fed thru pcb
hole
and chassis hole and load a speaker crimp connector on the end of the rod
to
pull back through, crossing fingers that it will not dislodge? I'm not
skilled in chopstick use.




Mail me off-group with a valid email address for receiving, Nigel

Arfa

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Default Marshall AS100D, of 2008


"Nutcase Kook"


** The AS100D has "Made in India" on the back panel - right ?

While valve heads MA50H & MA100H have "Made in Vietnam" on the back..



..... Phil








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Default Marshall AS100D, of 2008

Arfa Daily wrote in message
...


"N_Cook" wrote in message
...
No output unless in echo effects mode. Owner put away for 2 years.

Covered
in PbF & Rohs stickers.
Now I find no problem . Send/Return/footsw sockets are not active bypass
configuration. Anti-feedback on/off switch is iffy but I doubt would

kill
throughput .
Any known URL for a schematic out there?
Then how to reassemble the 4-off speaker wire routing, rod fed thru pcb
hole
and chassis hole and load a speaker crimp connector on the end of the

rod
to
pull back through, crossing fingers that it will not dislodge? I'm not
skilled in chopstick use.




Mail me off-group with a valid email address for receiving, Nigel

Arfa



will do

for the moment
The mute lines of the 2x LM3886 go to the ps, so only sw on/off muting.
Now the 3 sections of the amp are out of the chassis on the bench, to
explore the FX on/off line and the horrible white PbF solder "joints". The
designed-as skew-whiff digital FX board looks my sort of bodged
professionalism

A straight rod cannot pass through both pcb hole and chassis hole, so
probably chamfer off the edges of the crudely made pcb holes and then 4
pre-laid cords/wires to twist/temp fix through and to the sp wire crimps for
final re-assembly


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Default Marshall AS100D, of 2008

As the FX board is only held on by 1 nylon screw on the other side from the
header , so eminently loosable, I tried running with the pcb removed , but
normal amp action , sans-FX with FX sw in either position




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Default Marshall AS100D, of 2008

if the mixed 1 and 2 signal fails to get to the output amps then there is a
second route via the effects board, but that route is fixed , ie no header
connectors , switches or pot wipers, leaving dodgy pbf.
I cannot see how failing switches for the anti-feedback notch filters could
pulldown the ch1+ch2 mixer opamp.
Probably resolder all in that area


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Default Marshall AS100D, of 2008

Textbook logical fault-finding , shame PbF is not logical. If I make a
leaded component / wire link mechanical tester, anyone know what force you
should be able to apply without the lead pulling through the solder. I use
thin nose pliers and some undefined , but attempted consistency, amount of
finger applied force at the moment.

Wire link failed this pull test on one end and now that end is pulled
through the PbF, the other end rotates in its "joint" .
So mixed ch1 +ch2 from IC201p1 to the FX switch and FX board , including a
wire link, is ok (for now) and this failing link from there on towards yhe
other end of the pcb and the 68K/68K split out to the routes to the 2
output amps. So with failed link, signal through the FX board only


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Default Marshall AS100D, of 2008

for "leaded component " read components with wire leads, not components with
lead/tin solder


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Default Marshall AS100D, of 2008


"N_Cook" wrote in message
...
for "leaded component " read components with wire leads, not components
with
lead/tin solder




I read that as lead.


English must be quite a difficult language to learn.
Seems most school kids can't even manage it at all these days.



Gareth.


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Default OT. Marshall AS100D, of 2008

English must be quite a difficult language to learn.
Seems most school kids can't even manage it at all these days.



Gareth.



UK school kids that is.

I was looking for an apprentice some years ago and got loads of job
applications from a few colleges, through the local employment agency. You
know, out of the 30 or so applications, not one candidate could write any
better than I could in primary school.
To say I found that shocking is a gross understatement.



Gareth.




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Default OT. Marshall AS100D, of 2008



"Gareth Magennis" wrote in message
...
English must be quite a difficult language to learn.
Seems most school kids can't even manage it at all these days.



Gareth.



UK school kids that is.

I was looking for an apprentice some years ago and got loads of job
applications from a few colleges, through the local employment agency.
You know, out of the 30 or so applications, not one candidate could write
any better than I could in primary school.
To say I found that shocking is a gross understatement.



Gareth.



A guy that comes into one of our food joints is an exam marker. The missus
got talking to him about the state of education, and a couple of days later,
he brought in a GCSE level maths paper for 15 year olds. They apparently had
90 minutes to complete this paper, and were allowed to use a calculator. I
was able to finish it, in my head, in about 20 minutes. I think that I would
have been able to do the same at age 10, back in the days when we were
taught properly 40 odd years ago. The maths papers that we took back then at
age 15, were way, way above the level of this Mickey Mouse paper. The
standard even appears to have taken a nose dive since my own kids were that
age 10 years or so ago.

Last week, we had the 9 year old daughter of one of our relations staying
with us. She asked if she could borrow my wife's laptop, to do her maths
homework. Intrigued, we let her. She basically logged onto a website that
presented her with questions, and spaces to fill in the answers. When she is
finished, the program marks it and sends the result to her teacher. With
this lack of interaction between teacher and pupil, its no wonder that
education in the UK has fallen to the level that it is now. I always
considered myself a fairly average student, but I kid you not, I am now the
equivalent of a university professor to the kids ...

Has it declined like this in the U.S. also ?

Arfa

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Default OT. Marshall AS100D, of 2008

Gareth Magennis wrote in message
...
English must be quite a difficult language to learn.
Seems most school kids can't even manage it at all these days.



Gareth.



UK school kids that is.

I was looking for an apprentice some years ago and got loads of job
applications from a few colleges, through the local employment agency.

You
know, out of the 30 or so applications, not one candidate could write any
better than I could in primary school.
To say I found that shocking is a gross understatement.



Gareth.




I'm getting too much repair work in these days, how to find someone to take
off some of the load?
As an interim I will only have the phone ringer active perhaps two hours a
day, any other idea? Myself / friends/ local shop referrer + his friends ,
cannot find anyone to help out


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Default OT. Marshall AS100D, of 2008

On Apr 19, 5:58*pm, "Arfa Daily" wrote:
"Gareth Magennis" wrote in message


A guy that comes into one of our food joints is an exam marker. The missus
got talking to him about the state of education, and a couple of days later,
he brought in a GCSE level maths paper for 15 year olds. They apparently had
90 minutes to complete this paper, and were allowed to use a calculator. I
was able to finish it, in my head, in about 20 minutes. I think that I would
have been able to do the same at age 10, back in the days when we were
taught properly 40 odd years ago. The maths papers that we took back then at
age 15, were way, way above the level of this Mickey Mouse paper. The
standard even appears to have taken a nose dive since my own kids were that
age 10 years or so ago.

Last week, we had the 9 year old daughter of one of our relations staying
with us. She asked if she could borrow my wife's laptop, to do her maths
homework. Intrigued, we let her. She basically logged onto a website that
presented her with questions, and spaces to fill in the answers. When she is
finished, the program marks it and sends the result to her teacher. With
this lack of interaction between teacher and pupil, its no wonder that
education in the UK has fallen to the level that it is now. I always
considered myself a fairly average student, but I kid you not, I am now the
equivalent of a university professor to the kids ...

Has it declined like this in the U.S. also ?


US math performance was no great shakes to begin with -- look at any
league table of industrialized countries* over the years. The problem
starts in the primary grades, and to my mind is caused by a
fundamental mismatch: the sort of person who is drawn to spend their
day with young children seldom is drawn to spend their day doing math
problems. In fact most appear to fear and hate math. If your teacher
has no ability for teaching math, then you are unlikely to learn it on
your own.(And, unlike with language skills, which can be developed
outside the classroom through leisure activities such as reading for
pleasure, or by chatting or discussing current events; the random
student is unlikely to relax by doing some math problems.)

In fact, here computer assisted math instruction may save the day.
Instructional materials could include animations and live videos.
Exercises can adjust how difficult they are based on how each student
performs on them -- if the student misses too many midrange ones, the
computer could drop down to an easier level and so on. Finding out
what level each student operates comfortably at, and building from
there, should eliminate the panic of non-understanding.

* When I started at the university, I was amazed how far ahead the
foreign students were in math. Even people from countries like Peru
and Turkey.
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Default OT. Marshall AS100D, of 2008


I'm getting too much repair work in these days, how to find someone to
take
off some of the load?
As an interim I will only have the phone ringer active perhaps two hours a
day, any other idea? Myself / friends/ local shop referrer + his friends ,
cannot find anyone to help out




The problem is finding anyone competent enough not to ruin your
reputation/business. If all your repairs start coming back you will have a
whole load of extra stress and problems to the ones you have now.

My advice would be to stay a one man band and limit your repair intake.
e.g. refuse all Hi-fi, Pro-audio, or whatever section you least like to deal
with, or makes you the least money with the most effort.

I know what it like to have a 2 to 3 week backlog and more - dreading every
phone call because most of them are customers wanting to know why you
haven't repaired their gear yet.
Its a nightmare world of stress you just don't need.



Gareth.


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Default OT. Marshall AS100D, of 2008

Gareth Magennis wrote in message
...

I'm getting too much repair work in these days, how to find someone to
take
off some of the load?
As an interim I will only have the phone ringer active perhaps two hours

a
day, any other idea? Myself / friends/ local shop referrer + his friends

,
cannot find anyone to help out




The problem is finding anyone competent enough not to ruin your
reputation/business. If all your repairs start coming back you will have

a
whole load of extra stress and problems to the ones you have now.

My advice would be to stay a one man band and limit your repair intake.
e.g. refuse all Hi-fi, Pro-audio, or whatever section you least like to

deal
with, or makes you the least money with the most effort.

I know what it like to have a 2 to 3 week backlog and more - dreading

every
phone call because most of them are customers wanting to know why you
haven't repaired their gear yet.
Its a nightmare world of stress you just don't need.



Gareth.



Your probably right , and the blame culture/ excess litigation these days

In this game it would be nice for somenone to to take on those PbF failed
guitar input sockets and failed flimsey send/return bypass switches but even
those repairs it is possible for a numbskull to replace a header the wrong
way etc .

I intend not touching anything over 20 Kg at some point, I have the spring
balance , that cutoff going down in weight over time.
The telephone business of a timer to the phone ringer (so to the outside
world the phone is ringing) because most of my work comes via phone and this
should deter the friends of friends. Nothing against them as customers but
its just a way of cutting down the numbers.
Like the job application sifting business of rejecting all applications that
come in on anything other than white paper , just to reduce the numbers
to something manageable.









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Default OT. Marshall AS100D, of 2008

A guy that comes into one of our food joints is an exam marker.
The missus got talking to him about the state of education, and
a couple of days later, he brought in a GCSE level maths paper
for 15 year olds. They apparently had 90 minutes to complete this
paper, and were allowed to use a calculator. I was able to finish it,
in my head, in about 20 minutes. I think that I would have been able
to do the same at age 10, back in the days when we were taught
properly 40 odd years ago. The maths papers that we took back
then at age 15, were way, way above the level of this Mickey
Mouse paper. The standard even appears to have taken a nose-dive
since my own kids were that age 10 years or so ago.


The US of A is a country that believes the most-important thing in life --
other than trying to force your religious beliefs on other people -- is to
be "successful" (ie, wealthy and powerful). Getting a real education --
which includes science and the liberal arts -- is of no importance, unless
it promotes "success".

Ours is a profoundly anti-education, anti-intellectual country. This is
amazing, when you consider that most of the Founding Fathers were
intelligent, well-educated or well-read people.

I've never had trouble with math. Pardon the brag, but when I took the SATs
way back in 1965, I got an 800+ on the math part. * You read that right --
eight-hundred-plus. I asked about this. "How can you get a score higher than
800?" I was told 800 was not "perfect" -- just very high. And you could get
a score higher than /that/. Hence, the plus.

* I probably would have gotten an 800 on the English, if it hadn't been for
the analogies, which were thrown out several years ago.


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Default OT. Marshall AS100D, of 2008

I'm getting too much repair work in these days,
how to find someone to take off some of the load?


If you were local, perhaps I could help out by triaging the items -- making
a preliminary judgment as to what's wrong, disassembling them, etc.

If you do hire somebody, make sure they care about doing a proper repair,
that won't bounce back.


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Default OT. Marshall AS100D, of 2008

William Sommerwerck wrote in message
...
I'm getting too much repair work in these days,
how to find someone to take off some of the load?


If you were local, perhaps I could help out by triaging the items --

making
a preliminary judgment as to what's wrong, disassembling them, etc.

If you do hire somebody, make sure they care about doing a proper repair,
that won't bounce back.




It wouldn't be hiring anyone , just someone I can relay the contact details
of, if they can convince me they're any good. That referring shopkeeper
tried someone ten years ago and he was hopeless. I know what sort of test
questions I would ask and a check on his mechanical ability as well, some
people thes edays barely know how to use a screwdriver.


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Default OT. Marshall AS100D, of 2008

On Fri, 20 Apr 2012 08:29:00 +0100, "N_Cook"
wrote:

I'm getting too much repair work in these days, how to find someone to take
off some of the load?
As an interim I will only have the phone ringer active perhaps two hours a
day, any other idea? Myself / friends/ local shop referrer + his friends ,
cannot find anyone to help out


There are a lot of UK TV repair guys complaining that they are getting
less work and looking for new ideas (e.g laptop repairs).
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Default OT. Marshall AS100D, of 2008



"spamtrap1888" wrote in message
...
On Apr 19, 5:58 pm, "Arfa Daily" wrote:
"Gareth Magennis" wrote in message


A guy that comes into one of our food joints is an exam marker. The
missus
got talking to him about the state of education, and a couple of days
later,
he brought in a GCSE level maths paper for 15 year olds. They apparently
had
90 minutes to complete this paper, and were allowed to use a calculator.
I
was able to finish it, in my head, in about 20 minutes. I think that I
would
have been able to do the same at age 10, back in the days when we were
taught properly 40 odd years ago. The maths papers that we took back then
at
age 15, were way, way above the level of this Mickey Mouse paper. The
standard even appears to have taken a nose dive since my own kids were
that
age 10 years or so ago.

Last week, we had the 9 year old daughter of one of our relations staying
with us. She asked if she could borrow my wife's laptop, to do her maths
homework. Intrigued, we let her. She basically logged onto a website that
presented her with questions, and spaces to fill in the answers. When she
is
finished, the program marks it and sends the result to her teacher. With
this lack of interaction between teacher and pupil, its no wonder that
education in the UK has fallen to the level that it is now. I always
considered myself a fairly average student, but I kid you not, I am now
the
equivalent of a university professor to the kids ...

Has it declined like this in the U.S. also ?


US math performance was no great shakes to begin with -- look at any
league table of industrialized countries* over the years. The problem
starts in the primary grades, and to my mind is caused by a
fundamental mismatch: the sort of person who is drawn to spend their
day with young children seldom is drawn to spend their day doing math
problems. In fact most appear to fear and hate math. If your teacher
has no ability for teaching math, then you are unlikely to learn it on
your own.(And, unlike with language skills, which can be developed
outside the classroom through leisure activities such as reading for
pleasure, or by chatting or discussing current events; the random
student is unlikely to relax by doing some math problems.)

In fact, here computer assisted math instruction may save the day.
Instructional materials could include animations and live videos.
Exercises can adjust how difficult they are based on how each student
performs on them -- if the student misses too many midrange ones, the
computer could drop down to an easier level and so on. Finding out
what level each student operates comfortably at, and building from
there, should eliminate the panic of non-understanding.

* When I started at the university, I was amazed how far ahead the
foreign students were in math. Even people from countries like Peru
and Turkey.


An interesting evaluation. I always had the U.S. down as a country with good
all round education, much as we used to have. Certainly, all of the young
Americans that I have met on my travels there, have seemed polite at least,
which seems to me to be fundamental to getting educated. What has happened
here, is that a combination of liberal education policies, coupled with
over-liberal parenting, has resulted in primary school classes being filled
with disruptive and uncontrollable kids, in informal class situations that
do little or nothing to modify those behaviours. Add to that the fact that
the last two generations of teachers come from this background themselves,
and you have the degenerating standards that we have been seeing for the
last 25 years or more.

Once the early primary education has slipped to the level that it now has,
secondary and further education stands no realistic chance. If the kids
can't even read and write properly, what chance do they stand in other
subjects where they need to read, understand, and creatively write ? We now
have almost no scientists coming through our universities, which is very sad
when you consider that the UK once led the world in scientific discovery and
endeavour. Most universities now offer no maths courses at all. Science and
maths and English of course all go hand in hand, and if the students are not
getting a good enough grounding in core subjects like maths and English,
then any science subject will be a non-starter.

I find it all terribly sad and depressing. The world should advance, not
decline, but I guess that is the nature of the rise and collapse of great
civilisations, as has been seen many times throughout history.

Just a few weeks ago, I was reading a newspaper columnist who is a bit of a
bleeding-heart liberal, and she was defending educational standards on
behalf of her own kids, and was saying that she got fed up of listening to
people (like me presumably) who harped on about and decried the passing of a
golden age that never actually existed. I wanted to scream at the silly cow
that she was wrong wrong wrong, and that she was not qualified to comment as
she is not old enough to have been part of it.

Arfa



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Default OT. Marshall AS100D, of 2008

Arfa Daily wrote in message
...


"spamtrap1888" wrote in message
...
On Apr 19, 5:58 pm, "Arfa Daily" wrote:
"Gareth Magennis" wrote in message


A guy that comes into one of our food joints is an exam marker. The
missus
got talking to him about the state of education, and a couple of days
later,
he brought in a GCSE level maths paper for 15 year olds. They

apparently
had
90 minutes to complete this paper, and were allowed to use a

calculator.
I
was able to finish it, in my head, in about 20 minutes. I think that I
would
have been able to do the same at age 10, back in the days when we were
taught properly 40 odd years ago. The maths papers that we took back

then
at
age 15, were way, way above the level of this Mickey Mouse paper. The
standard even appears to have taken a nose dive since my own kids were
that
age 10 years or so ago.

Last week, we had the 9 year old daughter of one of our relations

staying
with us. She asked if she could borrow my wife's laptop, to do her

maths
homework. Intrigued, we let her. She basically logged onto a website

that
presented her with questions, and spaces to fill in the answers. When

she
is
finished, the program marks it and sends the result to her teacher.

With
this lack of interaction between teacher and pupil, its no wonder that
education in the UK has fallen to the level that it is now. I always
considered myself a fairly average student, but I kid you not, I am now
the
equivalent of a university professor to the kids ...

Has it declined like this in the U.S. also ?


US math performance was no great shakes to begin with -- look at any
league table of industrialized countries* over the years. The problem
starts in the primary grades, and to my mind is caused by a
fundamental mismatch: the sort of person who is drawn to spend their
day with young children seldom is drawn to spend their day doing math
problems. In fact most appear to fear and hate math. If your teacher
has no ability for teaching math, then you are unlikely to learn it on
your own.(And, unlike with language skills, which can be developed
outside the classroom through leisure activities such as reading for
pleasure, or by chatting or discussing current events; the random
student is unlikely to relax by doing some math problems.)

In fact, here computer assisted math instruction may save the day.
Instructional materials could include animations and live videos.
Exercises can adjust how difficult they are based on how each student
performs on them -- if the student misses too many midrange ones, the
computer could drop down to an easier level and so on. Finding out
what level each student operates comfortably at, and building from
there, should eliminate the panic of non-understanding.

* When I started at the university, I was amazed how far ahead the
foreign students were in math. Even people from countries like Peru
and Turkey.


An interesting evaluation. I always had the U.S. down as a country with

good
all round education, much as we used to have. Certainly, all of the young
Americans that I have met on my travels there, have seemed polite at

least,
which seems to me to be fundamental to getting educated. What has happened
here, is that a combination of liberal education policies, coupled with
over-liberal parenting, has resulted in primary school classes being

filled
with disruptive and uncontrollable kids, in informal class situations that
do little or nothing to modify those behaviours. Add to that the fact that
the last two generations of teachers come from this background themselves,
and you have the degenerating standards that we have been seeing for the
last 25 years or more.

Once the early primary education has slipped to the level that it now has,
secondary and further education stands no realistic chance. If the kids
can't even read and write properly, what chance do they stand in other
subjects where they need to read, understand, and creatively write ? We

now
have almost no scientists coming through our universities, which is very

sad
when you consider that the UK once led the world in scientific discovery

and
endeavour. Most universities now offer no maths courses at all. Science

and
maths and English of course all go hand in hand, and if the students are

not
getting a good enough grounding in core subjects like maths and English,
then any science subject will be a non-starter.

I find it all terribly sad and depressing. The world should advance, not
decline, but I guess that is the nature of the rise and collapse of great
civilisations, as has been seen many times throughout history.

Just a few weeks ago, I was reading a newspaper columnist who is a bit of

a
bleeding-heart liberal, and she was defending educational standards on
behalf of her own kids, and was saying that she got fed up of listening to
people (like me presumably) who harped on about and decried the passing of

a
golden age that never actually existed. I wanted to scream at the silly

cow
that she was wrong wrong wrong, and that she was not qualified to comment

as
she is not old enough to have been part of it.

Arfa



Perhaps there is a side issue that prople don't want to get their hands
dirty these days.
I arranged a talk by someone from The Culham labs , subject cold fusion
research. They find competent physics post-grads two a penny. But cannot
find competent welders/fitters/mechanics and technicians .



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