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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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#1
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JCM2000 DSL100
Hi,
just put a Marshall JCM2000, DSL100 on the bench. Looks nice ..... 3 output valves installed, 6CA7EH ( Electro-Harmonix, 02/12), only one of which works. Two, large mirror burn marks on the glass of one of the dead ones, but the OT and rest of amp seem OK. Pulled all the 6CA7s and checked the bias voltage on pin 5 of all 4 sockets = -43V at max setting. Played hot air onto the PCB near the octal sockets for about 20 seconds and re-checked. Pin 5 voltages had dropped to between 28V & 14 V. Oh **** !!!!! How did this amp ever survive for this long with such massive PCB leakage ??? The grid feed resistors are all 220kohms too !!!! Do Marshall actually have spare PCBs for this god awful POS any more ?? What sort of cost delivered to Sydney Australia ? ..... Phil |
#2
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JCM2000 DSL100
"Phil Allison" wrote in message ... Hi, just put a Marshall JCM2000, DSL100 on the bench. Looks nice ..... 3 output valves installed, 6CA7EH ( Electro-Harmonix, 02/12), only one of which works. Two, large mirror burn marks on the glass of one of the dead ones, but the OT and rest of amp seem OK. Pulled all the 6CA7s and checked the bias voltage on pin 5 of all 4 sockets = -43V at max setting. Played hot air onto the PCB near the octal sockets for about 20 seconds and re-checked. Pin 5 voltages had dropped to between 28V & 14 V. Oh **** !!!!! How did this amp ever survive for this long with such massive PCB leakage ??? The grid feed resistors are all 220kohms too !!!! Do Marshall actually have spare PCBs for this god awful POS any more ?? What sort of cost delivered to Sydney Australia ? .... Phil There is no reason why Marshall would not have these PCB's for sale. The last one I bought cost me just short of £50 including VAT and carriage. I guess if you could persuade them to ship to Sydney, the VAT would be deducted and you would pay VAT/import duty in Australia instead. They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. Cheers, Gareth. |
#3
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JCM2000 DSL100
On 11/02/2014 10:04, Gareth Magennis wrote:
"Phil Allison" wrote in message ... Hi, just put a Marshall JCM2000, DSL100 on the bench. Looks nice ..... 3 output valves installed, 6CA7EH ( Electro-Harmonix, 02/12), only one of which works. Two, large mirror burn marks on the glass of one of the dead ones, but the OT and rest of amp seem OK. Pulled all the 6CA7s and checked the bias voltage on pin 5 of all 4 sockets = -43V at max setting. Played hot air onto the PCB near the octal sockets for about 20 seconds and re-checked. Pin 5 voltages had dropped to between 28V & 14 V. Oh **** !!!!! How did this amp ever survive for this long with such massive PCB leakage ??? The grid feed resistors are all 220kohms too !!!! Do Marshall actually have spare PCBs for this god awful POS any more ?? What sort of cost delivered to Sydney Australia ? .... Phil There is no reason why Marshall would not have these PCB's for sale. The last one I bought cost me just short of £50 including VAT and carriage. I guess if you could persuade them to ship to Sydney, the VAT would be deducted and you would pay VAT/import duty in Australia instead. They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. Cheers, Gareth. Or you could get sculpting on what you have. Possible with small conical cintride/diamond bits but I now have a set of cintride tile-hole cutters for a quick neat job. Explained on a couple of M, on my file http://www.divdev.fsnet.co.uk/repair2l.htm IIRC one was thermally-kicked-off conductive pcb problem at a preamp valve and the other for output valves. Neither have bounced back to me and one of the owners I'm in regular contact with. You have to wonder if the replacement M boards are old stock from the original salt? contaminated board production run |
#4
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JCM2000 DSL100
"N_Cook" wrote in message ... On 11/02/2014 10:04, Gareth Magennis wrote: "Phil Allison" wrote in message ... Hi, just put a Marshall JCM2000, DSL100 on the bench. Looks nice ..... 3 output valves installed, 6CA7EH ( Electro-Harmonix, 02/12), only one of which works. Two, large mirror burn marks on the glass of one of the dead ones, but the OT and rest of amp seem OK. Pulled all the 6CA7s and checked the bias voltage on pin 5 of all 4 sockets = -43V at max setting. Played hot air onto the PCB near the octal sockets for about 20 seconds and re-checked. Pin 5 voltages had dropped to between 28V & 14 V. Oh **** !!!!! How did this amp ever survive for this long with such massive PCB leakage ??? The grid feed resistors are all 220kohms too !!!! Do Marshall actually have spare PCBs for this god awful POS any more ?? What sort of cost delivered to Sydney Australia ? .... Phil There is no reason why Marshall would not have these PCB's for sale. The last one I bought cost me just short of £50 including VAT and carriage. I guess if you could persuade them to ship to Sydney, the VAT would be deducted and you would pay VAT/import duty in Australia instead. They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. Cheers, Gareth. Or you could get sculpting on what you have. Possible with small conical cintride/diamond bits but I now have a set of cintride tile-hole cutters for a quick neat job. Explained on a couple of M, on my file http://www.divdev.fsnet.co.uk/repair2l.htm IIRC one was thermally-kicked-off conductive pcb problem at a preamp valve and the other for output valves. Neither have bounced back to me and one of the owners I'm in regular contact with. You have to wonder if the replacement M boards are old stock from the original salt? contaminated board production run No they are new boards, different colour, different screen printing. Nobody in their right mind would comtemplate such a thing. Surely. Gareth. |
#5
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JCM2000 DSL100
"Gareth Magennis" No they are new boards, different colour, different screen printing. ** I absolutely hope that IS the case. Nobody in their right mind would comtemplate such a thing. Surely. ** Right mind ?? "Nutcase Kook" ?? Surely you jest ........... FYI: Years ago, I established beyond all doubt that the PCB leakage problem with these models extends waaaay beyond the octal vales back into the phase splitter and earlier stages. PCB modifications and/or the use of fans are a dodge at best and I will never try them again. In this case, I'm gonna make the OWNER buy the new PCB and supply it to me. Soooo, if it turns out to be the wrong one OR has any kind of other problem - I can just hand it back. There are for too many *complete idiots* involved in the chain from Marshall in the UK to me. Just like the smug pommy bull****ter in these videos: https://www.youtube.com/watch?v=WeerxAO3oRU https://www.youtube.com/watch?v=rhe7qXP08qw Fair makes my skin crawl ....... ..... Phil |
#6
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JCM2000 DSL100
"Gareth Magennis" There is no reason why Marshall would not have these PCB's for sale. ** Double negatives like that are mind numbing. The last one I bought cost me just short of £50 including VAT and carriage. ** Was that long ago ? They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. ** Now, that is funny. So * I * have to prove to Marshall that * I * know what I am doing ????? They have SFA chance of ever proving the reverse. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. ** Thanks for the offer. Is there anything special about ordering such a PCB ? Or is the amp model number and serial number enough ? .... Phil |
#7
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JCM2000 DSL100
"Phil Allison" wrote in message ... "Gareth Magennis" There is no reason why Marshall would not have these PCB's for sale. ** Double negatives like that are mind numbing. The last one I bought cost me just short of £50 including VAT and carriage. ** Was that long ago ? They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. ** Now, that is funny. So * I * have to prove to Marshall that * I * know what I am doing ????? They have SFA chance of ever proving the reverse. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. ** Thanks for the offer. Is there anything special about ordering such a PCB ? Or is the amp model number and serial number enough ? ... Phil Nothing special, just ask for a DSL 100 board. Just for confirmation, both are marked JCM2-60-00. The new board has two extra connectors, Con 15 and Con16, as well as a relay which the old board does not. (Also Con 4 is not in the same orientation) This is probably so it can be used in the TSL 100 as well, the 3 channel version. Definitely not the same PCB at all. I think the DSL 50 also uses the same PCB, but with only 2 output valve sockets populated, but don't quote me on that cos my memory is a bit **** when it comes to things like that. Cheers, Gareth. |
#8
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JCM2000 DSL100
"Gareth Magennis" "Phil Allison" "Gareth Magennis" There is no reason why Marshall would not have these PCB's for sale. ** Double negatives like that are mind numbing. The last one I bought cost me just short of £50 including VAT and carriage. ** Was that long ago ? They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. ** Now, that is funny. So * I * have to prove to Marshall that * I * know what I am doing ????? They have SFA chance of ever proving the reverse. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. ** Thanks for the offer. Is there anything special about ordering such a PCB ? Or is the amp model number and serial number enough ? Nothing special, just ask for a DSL 100 board. Just for confirmation, both are marked JCM2-60-00. The new board has two extra connectors, Con 15 and Con16, as well as a relay which the old board does not. (Also Con 4 is not in the same orientation) This is probably so it can be used in the TSL 100 as well, the 3 channel version. Definitely not the same PCB at all. I think the DSL 50 also uses the same PCB, but with only 2 output valve sockets populated, but don't quote me on that cos my memory is a bit **** when it comes to things like that. ** Thanks again. I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. ..... Phil |
#9
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JCM2000 DSL100
"Phil Allison" wrote in message ... "Gareth Magennis" "Phil Allison" "Gareth Magennis" There is no reason why Marshall would not have these PCB's for sale. ** Double negatives like that are mind numbing. The last one I bought cost me just short of £50 including VAT and carriage. ** Was that long ago ? They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. ** Now, that is funny. So * I * have to prove to Marshall that * I * know what I am doing ????? They have SFA chance of ever proving the reverse. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. ** Thanks for the offer. Is there anything special about ordering such a PCB ? Or is the amp model number and serial number enough ? Nothing special, just ask for a DSL 100 board. Just for confirmation, both are marked JCM2-60-00. The new board has two extra connectors, Con 15 and Con16, as well as a relay which the old board does not. (Also Con 4 is not in the same orientation) This is probably so it can be used in the TSL 100 as well, the 3 channel version. Definitely not the same PCB at all. I think the DSL 50 also uses the same PCB, but with only 2 output valve sockets populated, but don't quote me on that cos my memory is a bit **** when it comes to things like that. ** Thanks again. I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. Well, what it says is what we already know, that a batch of faulty circuit boards were manufactured. Marshall have since redesigned it and the replacement seems to have sorted the problem out. What it also points out is that any bodge is likely to cost far more in labour than simply replacing the board. Unless you happen to live in Sydney perhaps. (Last one I bought was something around £35 +carriage +tax, that was 2 or 3 years ago now) And you would still be charging the customer a load of money for leaving a faulty board in the amp. Of course you could argue that Marshall should be offering a free exchange replacement on such boards, but that is a different debate. Cheers, Gareth. |
#10
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JCM2000 DSL100 PCB photo
http://imageshack.com/a/img845/570/o62e.jpg
The old PCB is the top one. Note Con15 below the bridge rectifier, it is connected to + and - of rectifier. Con 16 is below Con 8 and is just wired in paralell with it. The old PCB has an LDR, the new one a relay. There may be more differences, I haven't bothered to check thoroughly. Gareth. |
#11
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JCM2000 DSL100
"Gareth Magennis" "Phil Allison" ** Thanks again. I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. Well, what it says is what we already know, that a batch of faulty circuit boards were manufactured. ** Wot - a single batch ?? 1. How about 20 or 30 batches over a period of 5 or 6 years ? 2. How about publishing schems AND making many thousands of PCBs with 5.6k grid suppressors substituted for 220k ? 3. Have about never informing any of their overseas agents about it ? 4. How about 10s of thousands of EL34s ( and OTs) destroyed by the stupid problem ? 5. How about the hefty repair bills paid by Marshall owners and consequent bad will generated against hard working amp techs who were deliberately NOT informed of the REAL problem by the culprits - ie Marshall. Marshall have since redesigned it and the replacement seems to have sorted the problem out. ** You ARE ****ing joking !!!! You must be sucking those ****'s cocks so hard. Of course you could argue that Marshall should be offering a free exchange replacement on such boards, but that is a different debate. ** No it ****ing is not. It is nothing short of gross consumer fraud. ..... Phil |
#12
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JCM2000 DSL100 PCB photo
On 12/02/2014 10:20, Gareth Magennis wrote:
http://imageshack.com/a/img845/570/o62e.jpg The old PCB is the top one. Note Con15 below the bridge rectifier, it is connected to + and - of rectifier. Con 16 is below Con 8 and is just wired in paralell with it. The old PCB has an LDR, the new one a relay. There may be more differences, I haven't bothered to check thoroughly. Gareth. It would be nice to nail down exactly what the problem was with the pcb manufacture. As China made, probably affects other makes, which at lower voltages perhaps would take longer to emerge as a problem. I posited NaCl salt contamination to the filler material as it seems to give the right sort of temperature / conduction graph. The problem does not require the amps to be stored in sheds or garages, ie dampish, to induce the fault condition. |
#13
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JCM2000 DSL100
"Phil Allison" wrote in message ... "Gareth Magennis" "Phil Allison" ** Thanks again. I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. Well, what it says is what we already know, that a batch of faulty circuit boards were manufactured. ** Wot - a single batch ?? 1. How about 20 or 30 batches over a period of 5 or 6 years ? 2. How about publishing schems AND making many thousands of PCBs with 5.6k grid suppressors substituted for 220k ? 3. Have about never informing any of their overseas agents about it ? 4. How about 10s of thousands of EL34s ( and OTs) destroyed by the stupid problem ? 5. How about the hefty repair bills paid by Marshall owners and consequent bad will generated against hard working amp techs who were deliberately NOT informed of the REAL problem by the culprits - ie Marshall. Marshall have since redesigned it and the replacement seems to have sorted the problem out. ** You ARE ****ing joking !!!! You must be sucking those ****'s cocks so hard. Of course you could argue that Marshall should be offering a free exchange replacement on such boards, but that is a different debate. ** No it ****ing is not. It is nothing short of gross consumer fraud. .... Phil I'm not going to respond to that, it is disingenous on far too many levels. Gareth. |
#14
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JCM2000 DSL100 PCB photo
On 12/02/2014 10:20, Gareth Magennis wrote:
http://imageshack.com/a/img845/570/o62e.jpg The old PCB is the top one. Note Con15 below the bridge rectifier, it is connected to + and - of rectifier. Con 16 is below Con 8 and is just wired in paralell with it. The old PCB has an LDR, the new one a relay. There may be more differences, I haven't bothered to check thoroughly. Gareth. Knowing how precious some guitarists are, I'd rather mechanically adapt the original board rather than swap out to what may or may not be a sound-wise eqivalent replacement board. I've been there before, having spent out large spondulics for (not Marshall) a manufacturer's replacemnt board and ended up in a god-awful slanging match with an owner because the "sound" was all wrong and resulting with me being the time and money loser. |
#15
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JCM2000 DSL100
As a matter of interest, how old is this amplifier?
It'll be part of the serial number. Gareth. |
#16
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JCM2000 DSL100 PCB photo
"N_Cook" wrote in message ... On 12/02/2014 10:20, Gareth Magennis wrote: http://imageshack.com/a/img845/570/o62e.jpg The old PCB is the top one. Note Con15 below the bridge rectifier, it is connected to + and - of rectifier. Con 16 is below Con 8 and is just wired in paralell with it. The old PCB has an LDR, the new one a relay. There may be more differences, I haven't bothered to check thoroughly. Gareth. It would be nice to nail down exactly what the problem was with the pcb manufacture. As China made, probably affects other makes, which at lower voltages perhaps would take longer to emerge as a problem. I posited NaCl salt contamination to the filler material as it seems to give the right sort of temperature / conduction graph. The problem does not require the amps to be stored in sheds or garages, ie dampish, to induce the fault condition. In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, so possibly a combination of problems, not a single one. It would be unwise, IMHO, to assume ALL PCBs in the faulty batches ended up suffering from this problem. Any contamination/faults may have been quite clumpy in distribution, and/or down to a single individual during their shift. Who knows. Cheers, Gareth. |
#17
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JCM2000 DSL100
"Gareth Magennis" "Phil Allison" I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. Well, what it says is what we already know, that a batch of faulty circuit boards were manufactured. ** Wot - a single batch ?? 1. How about 20 or 30 batches over a period of 5 or 6 years ? 2. How about publishing schems AND making many thousands of PCBs with 5.6k grid suppressors substituted for 220k ? 3. Have about never informing any of their overseas agents about it ? 4. How about 10s of thousands of EL34s ( and OTs) destroyed by the stupid problem ? 5. How about the hefty repair bills paid by Marshall owners and consequent bad will generated against hard working amp techs who were deliberately NOT informed of the REAL problem by the culprits - ie Marshall. Marshall have since redesigned it and the replacement seems to have sorted the problem out. ** You ARE ****ing joking !!!! You must be sucking those ****'s cocks so hard. Of course you could argue that Marshall should be offering a free exchange replacement on such boards, but that is a different debate. ** No it ****ing is not. It is nothing short of gross consumer fraud. I'm not going to respond to that, it is disingenous on far too many levels. ** It is all simple fact, you lying pommy ****. Points 1,2 & 3 are detailed in the link I posted - which I seriously doubt you bothered to read. Points 4 & 5 are the unavoidable consequential outcomes. You have no response because you have been caught lying. Again. **** you. ..... Phil |
#18
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JCM2000 DSL100 PCB photo
"Gareth Magennis = Liar" In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, ** Regular carbon film types were fitted to early examples and later metal film - neither were the culprits. The first and worst case I saw ( a TSL 122 ) used metal film types. FYI, ****wit: NTC resistors in the bias feed would have HELPED the problem. .... Phil |
#19
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JCM2000 DSL100
On 02/11/2014 05:40 PM, Phil Allison wrote:
"Gareth Magennis" "Phil Allison" "Gareth Magennis" There is no reason why Marshall would not have these PCB's for sale. ** Double negatives like that are mind numbing. The last one I bought cost me just short of £50 including VAT and carriage. ** Was that long ago ? They did have a policy of only selling things that might kill people to bone fide engineers who wouldn't kill themselves or others with High Voltage, so you might also have to prove you are not a numpty. ** Now, that is funny. So * I * have to prove to Marshall that * I * know what I am doing ????? They have SFA chance of ever proving the reverse. If you're really stuck I have one here I could ship you, but with carriage and import taxes and already paid VAT @20% now, its going to end up bloody expensive. ** Thanks for the offer. Is there anything special about ordering such a PCB ? Or is the amp model number and serial number enough ? Nothing special, just ask for a DSL 100 board. Just for confirmation, both are marked JCM2-60-00. The new board has two extra connectors, Con 15 and Con16, as well as a relay which the old board does not. (Also Con 4 is not in the same orientation) This is probably so it can be used in the TSL 100 as well, the 3 channel version. Definitely not the same PCB at all. I think the DSL 50 also uses the same PCB, but with only 2 output valve sockets populated, but don't quote me on that cos my memory is a bit **** when it comes to things like that. ** Thanks again. I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. .... Phil Or read the article you showed us, which doesn't really say to give up, after all. |
#20
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JCM2000 DSL100 PCB photo
On 02/12/2014 05:29 AM, Gareth Magennis wrote:
"N_Cook" wrote in message ... On 12/02/2014 10:20, Gareth Magennis wrote: http://imageshack.com/a/img845/570/o62e.jpg The old PCB is the top one. Note Con15 below the bridge rectifier, it is connected to + and - of rectifier. Con 16 is below Con 8 and is just wired in paralell with it. The old PCB has an LDR, the new one a relay. There may be more differences, I haven't bothered to check thoroughly. Gareth. It would be nice to nail down exactly what the problem was with the pcb manufacture. As China made, probably affects other makes, which at lower voltages perhaps would take longer to emerge as a problem. I posited NaCl salt contamination to the filler material as it seems to give the right sort of temperature / conduction graph. The problem does not require the amps to be stored in sheds or garages, ie dampish, to induce the fault condition. In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, so possibly a combination of problems, not a single one. It would be unwise, IMHO, to assume ALL PCBs in the faulty batches ended up suffering from this problem. Any contamination/faults may have been quite clumpy in distribution, and/or down to a single individual during their shift. Who knows. Read the last 2 letters on Phil's link. The bias problem is on the Overdrive board. |
#21
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JCM2000 DSL100
"dave the stinking ****" I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. Or read the article you showed us, which doesn't really say to give up, ** Malcolm does not say that either, you stinking trolling moron. ..... Phil |
#22
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JCM2000 DSL100 PCB photo
"dave the trolling **** " Read the last 2 letters on Phil's link. ** Don't waste your time. The bias problem is on the Overdrive board. ** Like hell it is. .... Phil |
#23
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JCM2000 DSL100 PCB photo
"Phil Allison" wrote in message ... "Gareth Magennis = Liar" In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, ** Regular carbon film types were fitted to early examples and later metal film - neither were the culprits. The first and worst case I saw ( a TSL 122 ) used metal film types. FYI, ****wit: NTC resistors in the bias feed would have HELPED the problem. ... Phil Oh I see what you did there Phil, you changed this: In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, so possibly a combination of problems, not a single one. To this: In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, For one who is always complaining about snipping and changing the context, that takes the biscuit. You lying snipping changing the context Marsupial's dirty unwiped arse. Cheers, Gareth. |
#24
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JCM2000 DSL100 PCB photo
"Gareth Magennis" wrote in message ... "Phil Allison" wrote in message ... "Gareth Magennis = Liar" In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, ** Regular carbon film types were fitted to early examples and later metal film - neither were the culprits. The first and worst case I saw ( a TSL 122 ) used metal film types. FYI, ****wit: NTC resistors in the bias feed would have HELPED the problem. ... Phil Oh I see what you did there Phil, you changed this: In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, so possibly a combination of problems, not a single one. To this: In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, For one who is always complaining about snipping and changing the context, that takes the biscuit. You lying snipping changing the context Marsupial's dirty unwiped arse. Cheers, Gareth. Which kind of proves "Malcolm" is talking a load of ******** then. Gareth. |
#25
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JCM2000 DSL100 PCB photo
"Gareth Magennis = Stinking Liar"
In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, ** Regular carbon film types were fitted to early examples and later metal film - neither were the culprits. The first and worst case I saw ( a TSL 122 ) used metal film types. FYI, ****wit: NTC resistors in the bias feed would have HELPED the problem. In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, ** Utter crap. Some people who posted in that link HAVE worked out the real problem, ie the PCB itself - but others ( having never seen anything like it before) fell for red herrings. Such a weird fault is bound to cause confusion among valve amp techs - most of whom are not very bright . Like you. BTW: Try learning Ohms Law you stinking pommy LIAR !!!! .... Phil |
#26
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JCM2000 DSL100 PCB photo
"Nutcase Kook the ****wit Pommy Nut Case " Knowing how precious some guitarists are, I'd rather mechanically adapt the original board rather than swap out to what may or may not be a sound-wise eqivalent replacement board. ** Why were you not aborted ? |
#27
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JCM2000 DSL100 PCB photo
"Phil Allison" wrote in message ... "Gareth Magennis = Stinking Liar" In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, ** Regular carbon film types were fitted to early examples and later metal film - neither were the culprits. The first and worst case I saw ( a TSL 122 ) used metal film types. FYI, ****wit: NTC resistors in the bias feed would have HELPED the problem. In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, ** Utter crap. Some people who posted in that link HAVE worked out the real problem, ie the PCB itself - but others ( having never seen anything like it before) fell for red herrings. Such a weird fault is bound to cause confusion among valve amp techs - most of whom are not very bright . Like you. BTW: Try learning Ohms Law you stinking pommy LIAR !!!! ... Phil I learnt that once before and its a bit boring. Murphys law is a little more interesting. And by the way I see you have just repeated the snipped and contex changed post of mine above. That's not very sporting, now is it? You stinking half dried up pool of Wallaby vomit. Cheers, Gareth. |
#28
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Gareth Magennis = Stinking LIAR
"Gareth Magennis = Stinking Liar"
In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, ** Regular carbon film types were fitted to early examples and later metal film - neither were the culprits. The first and worst case I saw ( a TSL 122 ) used metal film types. FYI, ****wit: NTC resistors in the bias feed would have HELPED the problem. -------------------------------------------------------------------------- In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, ** Utter crap. Some people who posted in that link HAVE worked out the real problem, ie the PCB itself - but others ( having never seen anything like it before) fell for red herrings. Such a weird fault is bound to cause confusion among valve amp techs - most of whom are not very bright . While other are complete ****wits - like you. BTW: Try learning Ohms Law you stinking pommy LIAR !!!! NTC resistors in the bias feed would have HELPED the problem. BTW2: You drunk ? You sure sound like you are. .... Phil |
#29
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Phil Allison, lying content changing snipper
"Phil Allison" wrote in message ... "Gareth Magennis = Stinking Liar" In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, ** Regular carbon film types were fitted to early examples and later metal film - neither were the culprits. The first and worst case I saw ( a TSL 122 ) used metal film types. FYI, ****wit: NTC resistors in the bias feed would have HELPED the problem. -------------------------------------------------------------------------- In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, ** Utter crap. Some people who posted in that link HAVE worked out the real problem, ie the PCB itself - but others ( having never seen anything like it before) fell for red herrings. Such a weird fault is bound to cause confusion among valve amp techs - most of whom are not very bright . While other are complete ****wits - like you. BTW: Try learning Ohms Law you stinking pommy LIAR !!!! NTC resistors in the bias feed would have HELPED the problem. BTW2: You drunk ? You sure sound like you are. ... Phil No Phil, I don't drink during the day at work, you can do as you please. By the way, read my post again. You know, the one you snipped. It says: In this case the problem may have been exacerbated by incorrect value and possibly temperature co-efficient type of resistors fitted, if Phil's link is to be believed, I never mentioned NTC resistors at all. I quickly read that page before going to work this morning and merely re-iterated that Malcolm seemed to think the wrong type had been fitted. Which is exactly what I said. You lying content changing ****wit. Cheers, Gareth. |
#30
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JCM2000 DSL100
On 02/12/2014 06:35 AM, Phil Allison wrote:
"dave the stinking ****" I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. Or read the article you showed us, which doesn't really say to give up, ** Malcolm does not say that either, you stinking trolling moron. .... Phil I don't know Malcolm. The last couple letters are from someone else I think. Or maybe not. It's not important. I've only had a couple of those on my bench and aside from the general cheapness certainly no worse than many other amps. Now I am in an arid climate 25.6 miles from the sea, so that may be why I haven't noticed any 500 VDC HV peter tracks. |
#31
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JCM2000 DSL100
"dave" wrote in message ... On 02/12/2014 06:35 AM, Phil Allison wrote: "dave the stinking ****" I found this page that details the many problems techs have found with these Marshalls. http://www.lynx.net/~jc/TSL122.html Quote from Malcolm: " I have just been visiting your web site and had a look at your attempts to deal with one of the most diabolical amps ever to see the light of day. My advice to anyone given one of these thing to fix - drop it like a hot potato and run in the opposite direction. These things were doomed the moment they left the factory " . Says it all really. Or read the article you showed us, which doesn't really say to give up, ** Malcolm does not say that either, you stinking trolling moron. .... Phil I don't know Malcolm. The last couple letters are from someone else I think. Or maybe not. It's not important. I've only had a couple of those on my bench and aside from the general cheapness certainly no worse than many other amps. Now I am in an arid climate 25.6 miles from the sea, so that may be why I haven't noticed any 500 VDC HV peter tracks. I've had a little bit more time to look at that web page now. Seems to me about a lot of so called Engineers blowing their own trumpets and becoming Superheroes for sorting it out. But actually not really. The first time I came across this problem, I was totally confused. What I was seeing could not logically be happening. I changed everything in the Output stage, but still the same symptoms. Eventually I phoned Marshall, and spoke to one of their techs, who informed me that yes, there was a problem with the PCB's, and yes, I should replace it with a re-designed one. All admitted by Marshall up front, job done, sorted. Seems this problem is more about Ego's, than simply looking at the problem, finding the solution, and implementing it at the least possible cost. The best post on the site I found was this one, which kind of sums up what I have experienced perfectly. http://imageshack.com/a/img545/362/4pvn.jpg Most everything else is all Me Me Me. |
#32
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Gareth Magennis = Stinking LIAR
Do you realize that when you so viciously attack people who disagree with you
(whether they're right or wrong), you destroy the atmosphere needed for an intelligent conversation? |
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