Marshall JCM 2000, 1998

N

N_Cook

Guest
Blown primary of the mains Tx, isolated removed from chassis, draws 1.2 amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar primary
windings where stressed midpoint would show half way short and half measured
ohms?. I will poke around in the winding/ try delaminating out of curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper , any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source UK ? or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes
 
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws 1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper , any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source UK ? or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes
Click to expand...
We get parts direct from Marshall. Used to be a Marshall dealer, but we are
not any more, and they still supply us with parts ok, so it must not be a
requirement. It may be that you have to be a 'legitimate' business though,
and not just 'Joe Punter'.

Arfa
 
On Thu, 10 Mar 2011 14:26:34 +0000, N_Cook wrote:

Blown primary of the mains Tx, isolated removed from chassis, draws 1.2
amp at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok. DC of
primaries measure 1.2R and 2.2R, would they use 2 bifilar primary
windings where stressed midpoint would show half way short and half
measured ohms?. I will poke around in the winding/ try delaminating out
of curiosity but
stock fault/ batch fault ? Other than "marinating" in paint stripper ,
any tips on delaminating ?
Are replacements available from Marshall ? or a grey market source UK ?
or anyone use 2 or 3 separate Tx ? Googling Tx model Dagnall, TXMA
00061, D2105
only shows up suspiciously low priced dollar quotes
Click to expand...
http://www.mercurymagnetics.com/pages/mainframe.htm

Should ship internationally.



--
Live Fast Die Young, Leave A Pretty Corpse
 
Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:rZ5ep.75494$To7.65089@newsfe12.ams2...
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws 1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper ,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source UK ?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but we
are
not any more, and they still supply us with parts ok, so it must not be a
requirement. It may be that you have to be a 'legitimate' business though,
and not just 'Joe Punter'.

Arfa
Click to expand...

Any ball-park idea of cost for a Marshall replacement ?
 
On 10/03/2011 15:18, Arfa Daily wrote:
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws
1.2 amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper ,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source UK
? or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but we
are not any more, and they still supply us with parts ok, so it must not
be a requirement. It may be that you have to be a 'legitimate' business
though, and not just 'Joe Punter'.

Arfa
Click to expand...
I've had parts direct from Marshall also. I was never a Marshall
dealer, when you talk to their service dept, they soon suss you out as
competent or not. Great service and killer 'on hold' music on the
telephone ;)

Ron
 
At least its the outer 120V primary at fault and a split bobbin so once the
laminations are apart , easy to inspect. Tomorrow I will try a 125W iron
concentrating on the central sliver of the first "E". Laid thin ptfe sheet
heat insulation under the other 3 slivers. What will be the softening
temperature of the lacquer and any guesses as to time of heat application at
the exposed end only ? At least I can monitor the other end with a
pyrommeter.
 
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilas70$gc9$1@news.eternal-september.org...
Arfa Daily <arfa.daily@ntlworld.com> wrote in message
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"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws 1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper ,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source UK ?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but we
are
not any more, and they still supply us with parts ok, so it must not be a
requirement. It may be that you have to be a 'legitimate' business
though,
and not just 'Joe Punter'.

Arfa



Any ball-park idea of cost for a Marshall replacement ?
Click to expand...


Ball park between Ł20 and Ł30 inc P&P and VAT.
 
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"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws
1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar
primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper
,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source UK
?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but we
are
not any more, and they still supply us with parts ok, so it must not be
a
requirement. It may be that you have to be a 'legitimate' business
though,
and not just 'Joe Punter'.

Arfa



Any ball-park idea of cost for a Marshall replacement ?





Ball park between Ł20 and Ł30 inc P&P and VAT.
Click to expand...

Did you leave out some zeros? 200 to 300 GBP
eg
http://www.sowter.co.uk/acatalog/SOWTER_TRANSFORMERS_CLASSIC_AMPS_15.html
 
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news:ilcnm8$t7n$1@news.eternal-september.org...
seconf attempt

Gareth Magennis <sound.service@btconnect.com> wrote in message
news:2edep.106250$ts7.49007@newsfe14.ams2...


"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilas70$gc9$1@news.eternal-september.org...
Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:rZ5ep.75494$To7.65089@newsfe12.ams2...


"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws
1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar
primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper
,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source
UK
?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but
we
are
not any more, and they still supply us with parts ok, so it must not
be
a
requirement. It may be that you have to be a 'legitimate' business
though,
and not just 'Joe Punter'.

Arfa



Any ball-park idea of cost for a Marshall replacement ?





Ball park between Ł20 and Ł30 inc P&P and VAT.





Did you leave out some zeros? 200 to 300 GBP
eg
http://www.sowter.co.uk/acatalog/SOWTER_TRANSFORMERS_CLASSIC_AMPS_15.html
Click to expand...
No, I've bought quite a few Marshall transformers from Marshall, and they
are not expensive.
 
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news:ilcnm8$t7n$1@news.eternal-september.org...
seconf attempt

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news:2edep.106250$ts7.49007@newsfe14.ams2...


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"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws
1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar
primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint stripper
,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source
UK
?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but
we
are
not any more, and they still supply us with parts ok, so it must not
be
a
requirement. It may be that you have to be a 'legitimate' business
though,
and not just 'Joe Punter'.

Arfa



Any ball-park idea of cost for a Marshall replacement ?





Ball park between Ł20 and Ł30 inc P&P and VAT.





Did you leave out some zeros? 200 to 300 GBP
eg
http://www.sowter.co.uk/acatalog/SOWTER_TRANSFORMERS_CLASSIC_AMPS_15.html
Click to expand...
I wouldn't have thought so. I would have said that Gareth's estimate was
probably not far short of the mark, based on transformers that we've ordered
from them in the past. I've always found them pretty reasonable. Just give
them a call and ask. They're a friendly enough 'family' company. Jim
Marshall's daughter did run spares. As far as I know, she still does.

Arfa
 
"Nutcase Kook"
Any ball-park idea of cost for a Marshall replacement ?

Ball park between Ł20 and Ł30 inc P&P and VAT.


Did you leave out some zeros? 200 to 300 GBP
Click to expand...

** The Dagnall brand trannies that are fitted to modern Marshalls are all
made in India or Shi Lanka by starving children.

The design is way under sized for the job and quality is non existent.

Spares are cheap, IME.

Shame the fucking amps are not.





...... Phil
 
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"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis, draws
1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar
primary
windings where stressed midpoint would show half way short and half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint
stripper
,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source
UK
?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but
we
are
not any more, and they still supply us with parts ok, so it must not
be
a
requirement. It may be that you have to be a 'legitimate' business
though,
and not just 'Joe Punter'.

Arfa



Any ball-park idea of cost for a Marshall replacement ?





Ball park between Ł20 and Ł30 inc P&P and VAT.





Did you leave out some zeros? 200 to 300 GBP
eg
http://www.sowter.co.uk/acatalog/SOWTER_TRANSFORMERS_CLASSIC_AMPS_15.html



I wouldn't have thought so. I would have said that Gareth's estimate was
probably not far short of the mark, based on transformers that we've
ordered from them in the past. I've always found them pretty reasonable.
Just give them a call and ask. They're a friendly enough 'family' company.
Jim Marshall's daughter did run spares. As far as I know, she still does.

Arfa
Click to expand...

Is that George, Arfa?



Gareth.
 
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"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis,
draws
1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or so.
Secondaries measure l27V, 16.3V and 2V so that side presumably ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar
primary
windings where stressed midpoint would show half way short and
half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint
stripper
,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market source
UK
?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer, but
we
are
not any more, and they still supply us with parts ok, so it must not
be
a
requirement. It may be that you have to be a 'legitimate' business
though,
and not just 'Joe Punter'.

Arfa



Any ball-park idea of cost for a Marshall replacement ?





Ball park between Ł20 and Ł30 inc P&P and VAT.





Did you leave out some zeros? 200 to 300 GBP
eg
http://www.sowter.co.uk/acatalog/SOWTER_TRANSFORMERS_CLASSIC_AMPS_15.html



I wouldn't have thought so. I would have said that Gareth's estimate was
probably not far short of the mark, based on transformers that we've
ordered from them in the past. I've always found them pretty reasonable.
Just give them a call and ask. They're a friendly enough 'family'
company. Jim Marshall's daughter did run spares. As far as I know, she
still does.

Arfa


Is that George, Arfa?



Gareth.
Click to expand...
Indeed it is ! :)

They're quite close to where I live.

Arfa
 
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"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ilan3u$j8g$1@news.eternal-september.org...
Blown primary of the mains Tx, isolated removed from chassis,
draws
1.2
amp
at 20V variac "mains" and temp climbs 20 deg C in 4 minutes or
so.
Secondaries measure l27V, 16.3V and 2V so that side presumably
ok.
DC of primaries measure 1.2R and 2.2R, would they use 2 bifilar
primary
windings where stressed midpoint would show half way short and
half
measured
ohms?. I will poke around in the winding/ try delaminating out of
curiosity
but
stock fault/ batch fault ? Other than "marinating" in paint
stripper
,
any
tips on delaminating ?
Are replacements available from Marshall ? or a grey market
source UK
?
or
anyone use 2 or 3 separate Tx ? Googling Tx model
Dagnall, TXMA 00061, D2105
only shows up suspiciously low priced dollar quotes



We get parts direct from Marshall. Used to be a Marshall dealer,
but we
are
not any more, and they still supply us with parts ok, so it must
not be
a
requirement. It may be that you have to be a 'legitimate' business
though,
and not just 'Joe Punter'.

Arfa



Any ball-park idea of cost for a Marshall replacement ?





Ball park between Ł20 and Ł30 inc P&P and VAT.





Did you leave out some zeros? 200 to 300 GBP
eg
http://www.sowter.co.uk/acatalog/SOWTER_TRANSFORMERS_CLASSIC_AMPS_15.html



I wouldn't have thought so. I would have said that Gareth's estimate was
probably not far short of the mark, based on transformers that we've
ordered from them in the past. I've always found them pretty reasonable.
Just give them a call and ask. They're a friendly enough 'family'
company. Jim Marshall's daughter did run spares. As far as I know, she
still does.

Arfa


Is that George, Arfa?



Gareth.

Indeed it is ! :)

They're quite close to where I live.

Arfa
Click to expand...


Had no idea she was part of the family!

Marshall are top of my list for spares supply and pricing, and George is
great to deal with and knows her stuff.


Gareth.
 
Is that George, Arfa?



Gareth.

Indeed it is ! :)

They're quite close to where I live.

Arfa



Had no idea she was part of the family!

Marshall are top of my list for spares supply and pricing, and George is
great to deal with and knows her stuff.


Gareth.
Click to expand...
I've always found them very good - except when they are on stock-take !
Then, you can wait a couple of weeks for your parts ... But yes, in general,
anything you need, and very reasonably priced.

The one problem that I have got with them, is that dreadful system of
providing access to their service information. I actually find it difficult
to use, and to search, and on several occasions, have 'caught them out' with
sections of schematic that simply aren't on there. I'm sure they thought it
was a good idea to have their service info archive 'front ended' by that
Image Bank user interface, and then to give access only to registered
(=pre-approved by their service department) users, but every time I go there
to download a manual, I just find it an awkward and frustrating process.

A long time ago, I found another Marshall specialist site, and they have an
archive of pretty much everything that Marshall have ever produced, right
back to the start, arranged by 'class' and date. I always go there first to
look for service info, and treat Marshall's Image Bank as a port of last
resort. I wish, if they are basically happy to let people have service info,
they would just list everything, and let you get it on a one-click download,
as other manufacturers do. I can sort of understand that they would prefer
to have some control over who they are giving data out to in order to try to
preserve a degree of professionalism in repairs to their equipment, but
given the fact that they must know that info on every one of their products
is already out there for download by the determined searcher, it just seems
a bit 'prissy' of them to force this poorly designed service info search and
download software on their registered users. They could still restrict
registered users to a password protected area on the website, that gave
access to a simple list of all the manuals available.

Arfa
 
Normal single filament winding. Normal failure mode , for slapdash wound Tx
these days. Slipped turn at one end of a layer dropping into a lower layer,
then presumably chaffing of lacquer to marginally spot weld. Not at all
obvious "weld" point , about 80 turns from lead out of outer primary. 195
turns in all of .75mm wire for one 120V primary. Not a problem here as 240 V
use, but would be for this Tx used in USA . There is tape covering the inner
primary but not extended at the leadout point of the inner primary so first
turn of the outer primary directly crosses that point so a full short is
very likely there with a bit of normal in service vibration/ chaffing. For
240V use those 2 points are at near enough same mid-mains potential (2 tails
to options bridging point on pcb)
At least I now know how to delaminate the E/I iron laminations.
 
"Nutcase Kook"
Normal single filament winding. Normal failure mode , for slapdash wound
Tx
these days. Slipped turn at one end of a layer dropping into a lower
layer,
then presumably chaffing of lacquer to marginally spot weld.

Not at all
obvious "weld" point , about 80 turns from lead out of outer primary. 195
turns in all of .75mm wire for one 120V primary. Not a problem here as 240
V
use, but would be for this Tx used in USA . There is tape covering the
inner
primary but not extended at the leadout point of the inner primary so
first
turn of the outer primary directly crosses that point so a full short is
very likely there with a bit of normal in service vibration/ chaffing.
Click to expand...
** The turns wound on that transformer do no move or chaff - you wanker.

Those Dagnall power transformers ( TMXA00061 etc) are made with low temp
grade enamel coating the copper and the tranny is under sized for the job it
has to do - not to mention working in a very high ambient temp from the heat
of the output valves.

As a result the windings run DAMN hot, the enamel gets soft and when two
soft spots meet under pressure you can get a short.

I have THREE dead ( internally shorted) examples of the exact same tranny
sitting here right now.


..... Phil
 
Marshall replacement Ł46 , same duff construction as this one?
 
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ill2ur$7hv$1@news.eternal-september.org...
Marshall replacement Ł46 , same duff construction as this one?
Click to expand...
I would expect it to probably be a ringer for what was already in there. If
the amp is really from 1998, then duff construction or not, it ain't done
bad, and if the new one does another 13 years, it's not going to come back
on you, is it ? And, if in the intervening 13 years since it was made,
Marshall have had a lot of them fail, then maybe they've taken this up with
Dagnell, and got them to improve the situation ? I would stop agonising over
it, and just stick the new one in, and write out the hundred quid bill for
the owner ...

Arfa
 
"N_Cook"
Marshall replacement Ł46 , same duff construction as this one?
Click to expand...
** Of course.

Only way to fix the problem is to find someone willing to rewind the
original transformer with high temp enamel wire - ie 180C rate instead of
the 120C rated stuff used by Dagnall.

Or you could fit a small fan blowing on the tranny....


...... Phil
 
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