Home |
Search |
Today's Posts |
|
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. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
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 |
#2
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
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 http://www.mercurymagnetics.com/pages/mainframe.htm Should ship internationally. -- Live Fast Die Young, Leave A Pretty Corpse |
#3
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"N_Cook" wrote in message ... 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 |
#4
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
Arfa Daily wrote in message
... "N_Cook" wrote in message ... 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 ? |
#5
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
On 10/03/2011 15:18, Arfa Daily wrote:
"N_Cook" wrote in message ... 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 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 |
#6
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
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. |
#7
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... 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 £20 and £30 inc P&P and VAT. |
#8
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
seconf attempt
Gareth Magennis wrote in message ... "N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... 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 £20 and £30 inc P&P and VAT. Did you leave out some zeros? 200 to 300 GBP eg http://www.sowter.co.uk/acatalog/SOW...C_AMPS_15.html |
#9
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"N_Cook" wrote in message ... seconf attempt Gareth Magennis wrote in message ... "N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... 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 £20 and £30 inc P&P and VAT. Did you leave out some zeros? 200 to 300 GBP eg http://www.sowter.co.uk/acatalog/SOW...C_AMPS_15.html No, I've bought quite a few Marshall transformers from Marshall, and they are not expensive. |
#10
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"N_Cook" wrote in message ... seconf attempt Gareth Magennis wrote in message ... "N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... 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 £20 and £30 inc P&P and VAT. Did you leave out some zeros? 200 to 300 GBP eg http://www.sowter.co.uk/acatalog/SOW...C_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 |
#11
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Nutcase Kook" Any ball-park idea of cost for a Marshall replacement ? Ball park between £20 and £30 inc P&P and VAT. Did you leave out some zeros? 200 to 300 GBP ** 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 ****ing amps are not. ...... Phil |
#12
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Arfa Daily" wrote in message ... "N_Cook" wrote in message ... seconf attempt Gareth Magennis wrote in message ... "N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... 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 £20 and £30 inc P&P and VAT. Did you leave out some zeros? 200 to 300 GBP eg http://www.sowter.co.uk/acatalog/SOW...C_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. |
#13
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Gareth Magennis" wrote in message ... "Arfa Daily" wrote in message ... "N_Cook" wrote in message ... seconf attempt Gareth Magennis wrote in message ... "N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... 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 £20 and £30 inc P&P and VAT. Did you leave out some zeros? 200 to 300 GBP eg http://www.sowter.co.uk/acatalog/SOW...C_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 |
#14
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Arfa Daily" wrote in message ... "Gareth Magennis" wrote in message ... "Arfa Daily" wrote in message ... "N_Cook" wrote in message ... seconf attempt Gareth Magennis wrote in message ... "N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... 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 £20 and £30 inc P&P and VAT. Did you leave out some zeros? 200 to 300 GBP eg http://www.sowter.co.uk/acatalog/SOW...C_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 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. |
#15
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
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. 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 |
#16
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
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. |
#17
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"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. ** The turns wound on that transformer do no move or chaff - you ******. 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 |
#18
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
Marshall replacement £46 , same duff construction as this one?
|
#19
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"N_Cook" wrote in message ... Marshall replacement £46 , same duff construction as this one? 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 |
#20
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"N_Cook" Marshall replacement £46 , same duff construction as this one? ** 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 |
#21
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Phil Allison" wrote in message ... "N_Cook" Marshall replacement £46 , same duff construction as this one? ** 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 I'll go with Arfa's suggestion. Pay the £46 and when it breaks in 13 years time, we can then re-assess the situation. Though the small fan idea is a good one IMHO. Might extend that period to 26 years or more. Gareth. |
#22
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Gareth Magennis" "Phil Allison" "Nutcase Kook" Marshall replacement £46 , same duff construction as this one? ** 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.... I'll go with Arfa's suggestion. ** Makes you as big a ****ing halfwit as he is. Pay the £46 and when it breaks in 13 years time, ** HUH ??? What sort of madness makes do you think the problem has a 13 year delay built in ?????? That POS tranny can fail in the first few hours of use !!! Only has to overheat enough to soften the enamel on the wire - and overheat it surely will cos it is not correctly sized ( in terms of VA rating) for the job it has to do. ...... Phil |
#23
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Phil Allison" wrote in message ... "Gareth Magennis" "Phil Allison" "Nutcase Kook" Marshall replacement £46 , same duff construction as this one? ** 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.... I'll go with Arfa's suggestion. ** Makes you as big a ****ing halfwit as he is. I wonder what that makes you then, Philip ? Actually, don't answer that. We all already know that you are a half-baked **** ... :-) Arfa |
#24
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Arfa Daily" ** Please come to Sydney - Arfa. Just buy a one way ticket, cos that is all you will need. Go straight to Circular Quay from Mascot airport and then into any pub with your stupid, whiny pommy voice and tell everyone there all your brilliant thoughts. The sharks in Sydney harbour will be picking your bones by nightfall. ...... Phil |
#25
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
Arfa Daily wrote in message
... "N_Cook" wrote in message ... Marshall replacement £46 , same duff construction as this one? 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 What is the point of CE "compliance" testing etc if 2 layers of lacquer to resist 120V av . At one time, before CE marking, all these Tx tails had extra sleeving over them to avoid this problem. |
#26
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Phil Allison" wrote in message ... "Gareth Magennis" "Phil Allison" "Nutcase Kook" Marshall replacement £46 , same duff construction as this one? ** 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.... I'll go with Arfa's suggestion. ** Makes you as big a ****ing halfwit as he is. Pay the £46 and when it breaks in 13 years time, ** HUH ??? What sort of madness makes do you think the problem has a 13 year delay built in ?????? That POS tranny can fail in the first few hours of use !!! Only has to overheat enough to soften the enamel on the wire - and overheat it surely will cos it is not correctly sized ( in terms of VA rating) for the job it has to do. ..... Phil That may be more of a problem in the heat of Shark Infested Sydney than the cold wet miserable UK, otherwise I would be changing these transformers all the time and I am not. I say again I think the fan idea is a good cheap easy solution, but not one I personally would bother with, though Mr Cook may rise and eyebrow or two of interest. Gareth. |
#27
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... Marshall replacement £46 , same duff construction as this one? 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 What is the point of CE "compliance" testing etc if 2 layers of lacquer to resist 120V av . At one time, before CE marking, all these Tx tails had extra sleeving over them to avoid this problem. What indeed? agreed. Unfortunately, that's just the world that we live in now. Long ago, I gave up trying to change the situation, got over it, and just got on with making a living ... Put the new tranny in, write up the bill, and move on to the next one :-) Arfa |
#28
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Phil Allison" wrote in message ... "Arfa Daily" ** Please come to Sydney - Arfa. Just buy a one way ticket, cos that is all you will need. Go straight to Circular Quay from Mascot airport and then into any pub with your stupid, whiny pommy voice and tell everyone there all your brilliant thoughts. The sharks in Sydney harbour will be picking your bones by nightfall. ..... Phil You do have a vivid imagination, Philip. The last place on earth I would want to go, is anywhere you are. Stupid person ... :-) Arfa |
#29
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Gareth Magennis" I'll go with Arfa's suggestion. ** Makes you as big a ****ing halfwit as he is. Pay the £46 and when it breaks in 13 years time, ** HUH ??? What sort of madness makes do you think the problem has a 13 year delay built in ?????? That POS tranny can fail in the first few hours of use !!! Only has to overheat enough to soften the enamel on the wire - and overheat it surely will cos it is not correctly sized ( in terms of VA rating) for the job it has to do. That may be more of a problem in the heat of Shark Infested Sydney than the cold wet miserable UK, ** So it is always " cold wet and miserable " INSIDE a venue in summer plus INSIDE a Marshall valve amp playing " Death Metal " riffs to hundreds of head bangers in the UK - is it ?? God, what a ****wit you are. I say again I think the fan idea is a good cheap easy solution, ** The easy and engineering wise final solution is the re-wind I suggested. **** head. ..... Phil |
#30
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Phil Allison" wrote in message ... "Gareth Magennis" I'll go with Arfa's suggestion. ** Makes you as big a ****ing halfwit as he is. Pay the £46 and when it breaks in 13 years time, ** HUH ??? What sort of madness makes do you think the problem has a 13 year delay built in ?????? That POS tranny can fail in the first few hours of use !!! Only has to overheat enough to soften the enamel on the wire - and overheat it surely will cos it is not correctly sized ( in terms of VA rating) for the job it has to do. That may be more of a problem in the heat of Shark Infested Sydney than the cold wet miserable UK, ** So it is always " cold wet and miserable " INSIDE a venue in summer plus INSIDE a Marshall valve amp playing " Death Metal " riffs to hundreds of head bangers in the UK - is it ?? God, what a ****wit you are. I say again I think the fan idea is a good cheap easy solution, ** The easy and engineering wise final solution is the re-wind I suggested. **** head. .... Phil Just gone through my database. From February 2005 to present I have replaced 2 mains transformers and 2 Output transformers in JCM2000's. If there was a particular problem with JCM2000 mains TX's in the UK I would have expected rather more than this. Gareth. |
#31
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
Arfa Daily wrote in message
news "N_Cook" wrote in message ... Arfa Daily wrote in message ... "N_Cook" wrote in message ... Marshall replacement £46 , same duff construction as this one? 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 What is the point of CE "compliance" testing etc if 2 layers of lacquer to resist 120V av . At one time, before CE marking, all these Tx tails had extra sleeving over them to avoid this problem. What indeed? agreed. Unfortunately, that's just the world that we live in now. Long ago, I gave up trying to change the situation, got over it, and just got on with making a living ... Put the new tranny in, write up the bill, and move on to the next one :-) Arfa For balance I got a quote from proper tx winders Majestic , just down the road http://www.transformers.uk.com/brochure.pdf for a one off , custom/semicustom build from scratch , to specified V & A of the 3 secondaries. Somewhere between 50 and 70 GBP plus VAT plus carriage, about 2 week turn around |
#32
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Nutcase Kook " For balance I got a quote from proper tx winders Majestic , just down the road http://www.transformers.uk.com/brochure.pdf for a one off , custom/semicustom build from scratch , to specified V & A of the 3 secondaries. Somewhere between 50 and 70 GBP plus VAT plus carriage, about 2 week turn around ** That is a very reasonable price. But did you ask them to make a new tranny with the exact same stack size and through chassis design as the Dagnall ones ?? Were they offering you a custom toroidal tranny by any chance?? ...... Phil |
#33
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Gareth Magennis is an utter ASS " I'll go with Arfa's suggestion. ** Makes you as big a ****ing halfwit as he is. Pay the £46 and when it breaks in 13 years time, ** HUH ??? What sort of madness makes do you think the problem has a 13 year delay built in ?????? That POS tranny can fail in the first few hours of use !!! Only has to overheat enough to soften the enamel on the wire - and overheat it surely will cos it is not correctly sized ( in terms of VA rating) for the job it has to do. That may be more of a problem in the heat of Shark Infested Sydney than the cold wet miserable UK, ** So it is always " cold wet and miserable " INSIDE a venue in summer plus INSIDE a Marshall valve amp playing " Death Metal " riffs to hundreds of head bangers in the UK - is it ?? God, what a ****wit you are. I say again I think the fan idea is a good cheap easy solution, ** The easy and engineering wise final solution is the re-wind I suggested. Just gone through my database. ** Go shove you stupid ****ing database up you stupid fat arse !! Engineering facts are F A C T S !! You pathetic, pommy DUMBASS !! ..... Phil |
#34
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
"Phil Allison" wrote in message ... "Gareth Magennis is an utter ASS " I'll go with Arfa's suggestion. ** Makes you as big a ****ing halfwit as he is. Pay the £46 and when it breaks in 13 years time, ** HUH ??? What sort of madness makes do you think the problem has a 13 year delay built in ?????? That POS tranny can fail in the first few hours of use !!! Only has to overheat enough to soften the enamel on the wire - and overheat it surely will cos it is not correctly sized ( in terms of VA rating) for the job it has to do. That may be more of a problem in the heat of Shark Infested Sydney than the cold wet miserable UK, ** So it is always " cold wet and miserable " INSIDE a venue in summer plus INSIDE a Marshall valve amp playing " Death Metal " riffs to hundreds of head bangers in the UK - is it ?? God, what a ****wit you are. I say again I think the fan idea is a good cheap easy solution, ** The easy and engineering wise final solution is the re-wind I suggested. Just gone through my database. ** Go shove you stupid ****ing database up you stupid fat arse !! Engineering facts are F A C T S !! You pathetic, pommy DUMBASS !! .... Phil My facts are real life experience long term test facts. Can't get a lot more factual than that, eh Phil. Gareth. |
#35
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
Or perhaps he'll get his head stomped on by an irate kangaroo...
Disembowelment from a kick is more likely. Herbivores are more dangerous than carnivores. |
#36
Posted to sci.electronics.repair
|
|||
|
|||
Marshall JCM 2000, 1998
Added a 12V 1.5 inch fan at the Tx. Using the unused heater tag for main
mount of the fan to solder a solder tag then that bolted to the fan. Setting fan at 20 degrees to the horizontal and cutting and fitting a shroud from that red impregnated cardboard stuff to direct the flow into one side , up, over top and back out the other side between windings and bobbin. As secondary side gets hotter than primary , fan positioned mainly on that side Air flow checked using a joss stick. Perhaps next time using some DC from the amp rather than bridge rect and cap off the heater supply as light current drops in the diodes bring it down to less than 9V . Retained the template for the shroud for the next one of these to attend to. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Marshall JCM 2000 | Electronics Repair | |||
Installing A 1985 Delta Uniguard On A 1998 Unisaw | Woodworking | |||
ID Theft From 1998 | Home Ownership | |||
ID Theft From 1998 | Home Ownership | |||
Trouble with Sat Nav CD-ROM drive in a 1998 Audi A8 | Electronics Repair |