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    DSL 50 Not Working

    Hi! again. The latest results. I plugged my guitar into the return socket of the effects loop on the back as suggested, and again got nothing on the 4/8 Ohm outputs. When I plugged into the 16 Ohm output I'm getting sound, but not good and crackly! is the best way to describe it. I then plugged...
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    DSL 50 Not Working

    Hi! again, sorry for the delay, but have been really busy. I've just measured for continuity on all 3 output sockets. 16 Ohm Socket = 0.4R Both 4/8 Ohm Sockets = No continuity at all! Can I presume this is not good?
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    Question for you guys that make a living as techs.

    Hi! Les, I actually understand all of your theory on here. Very well explained by the way. But then again, as a Domestic Electrician, and an Instructor, I suppose I should lol! I've actually found a great set of videos on Youtube that may be of some use to some of our members...
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    Need a refret!

    A refret on a Les Paul is quite a big job. As mentioned on here, a fret dress is probably the best option as long as your frets are not to badly grooved. I've done a few now and you have to be very careful with the neck binding, but as long as you are careful you can do it yourself. If you don't...
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    Question for you guys that make a living as techs.

    I'm actually an Electrical Instructor. However I am a Domestic Electrician by trade and therefore only really understand house wiring etc. I've also been repairing guitars for some years now, but have never really understood Electronics when you put all these components together in an amp...
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    DSL 50 Not Working

    Readings as requested. V7 not included as almost identical. Hope this is legible this time V6 Pin 1 0.01v DC Pin 1 1v AC Pin 2 0v DC Pin 2 3v AC Pin 3 458v DC Pin 3 1.7v AC Pin 4 448v DC Pin 4 0.18v AC Pin 5 -31.5v DC Pin 5 0.02v AC Pin 7 0.0v DC Pin 7 3.0v AC Pin 8 0v DC...
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    DSL 50 Not Working

    Hi! I think you could be right about the connection problem I've enclosed a pic of the EL34 Spec Sheet. You can see the problem that I'm having with the pinout. The spec sheet does not specify whether the pin numbers are from the top or underneath. It looks to me as if I am looking at the...
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    DSL 50 Not Working

    Hi! again Scat7s, I've just done some more pinout checks, and quess what. Unbelievable! Although very low readings on most of the pins, now getting 454v DC on pin 5 and 441v DC on pin 6. V7 is almost identical. I removed and replaced the main circuit board to check some...
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    DSL 50 Not Working

    When I checked the tube pins on the board as you say, I probably did it wrong. When I looked at the tube sockets, they are numbered. However I don't think this represents the pin numbers. If I was to look at the tube from the bottom, can I presume that starting on the left of the gap they are...
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    DSL 50 Not Working

    Hi! again, the fuses are situated either side of the mains plug socket so very easy to find and check. I checked these, but as I said nothing would power up if the fuses were blown. I have the schematic that you put the link to, the fuse holder says T500MA on it. The mains fuse is...
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    Tech Help Needed Please for JCM 2000 DSL 50

    Thanks Ken, Unfortunately I don't have a scope but I'm quite capable of testing components if I know what I'm looking for. The marshall circuit diagram has no test points indicated or voltages for any sort of reference. The only reason I changed the output transformer was because...
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    DSL 50 Not Working

    Hi! again, Just done some of the recommended testing that you suggested. I'm getting nothing on the HT at pins 3&4 of both the power valves (all less than 1 volt. I then checked the heater pins on pins 2&7 and again reading almost nothing, all under 1 volt. I checked both fuses and...
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    Tech Help Needed Please for JCM 2000 DSL 50

    Hi! AV, I am getting a very low distorted sound from the 16 Ohm output, but nothing from the others. I've changed the output transformer for a brand new one, so don't think thats the problem. I'll definately check what you've suggested though. Thanks Ade
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    DSL 50 Not Working

    Hi! again. We seem to be having a bit of a language barrier problem here lol! When I say mains fuse, I mean where the mains lead plugs in to the back of the amp. The power valves are actually powering up ( I presume these are the heaters) so the fuses must be OK. I think perhaps I'll check again...
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    DSL 50 Not Working

    Hi! again, as I said, I'm not too sure with tubes. The numbers that I've used are actually on the top of the tube sockets. I'm checking them from the solder joints on the circuit board from underneath though, so it's possible that I've got them around the wrong way. I'll have another go tomorrow...
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    DSL 50 Not Working

    I hope you can read this. It did'nt look anything like this when I typed it out Hopefully you will see that the first readings on the left are for V6 DC and AC and the same on the right for V7 Ade
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    DSL 50 Not Working

    Hi! again Scat7S. I really should have mentioned that I teach Electrical Principles and how to use Test Equipment, so testing is no problem. I am however a Domestic Electrician by trade, and therefore not really into Electronics. I understand the principles of Transistors, Diodes, Resistors...
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    DSL 50 Not Working

    Hi! again, just got your reply, but I'm at work at the moment. Will check out the voltages on both power valves as soon as I get in from work tonight and get back to you. Ade
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    DSL 50 Not Working

    Hi! again. I've had a look at the Marshall Circuit Diagram, and it's not very clear. I can't see where the power valves get there DC supply from unless they are acting as rectifier valves. (not sure about this) It looks to me like Pins 2 & 6 are the Heater Pins, 1(G3), 4(G2) & 5(G1) are Grids...
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    DSL 50 Not Working

    The latest edition of the DSL 50 Tests. I've checked for anything obvious, i.e. burned out Resistors etc and can't seem to find anything. I put a brand new Output Transformer in just in case, and now the Bias on one side is about 60mv and the other about 50mv. The bias pots are as low as they...

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