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Old 1st April 2007, 06:20 PM   #1
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Default el84 1 channel stopped working help

el84 1 channel stopped working help

Can anyone help me please, I have a problem with my el84. its been a cracking little amp I have had it for about 4 months, the warrantee on this amp wasn't worth having it will have to go back to china to be fixed at all my cost and I will also be without it for around 2 months, that's if I ever see it again. All the valves work fine its just that the 1 right channel has totally stopped working I have swapped the tubes and speakers etc but nothing works the channel is dead, The units rear body also doesn't get hot like it used to when it was working fine. Im no electronics expert and have little knowledge of circuits, but I have comon sense and I am a dab hand with a soldering iron and im sure with some guidance I could fix it but I don't know where to start can anyone help, the actual amp seems pretty basic but as I said I dont know where to start, It would be greatly appreciated. I love this little amp and there is nobody local who can help, I could send detailed photos of individual parts and anything else thats needed. Hope theres someone who can help.

e.davies2@virgin.net
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Old 1st April 2007, 07:02 PM   #2
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If you aren't comfortable with electronics, you should be VERY wary of poking around inside, so you are going to need hands on help....

One of our locals has the same (or incredibly similar) amp, i have alerted him.

Can you take good pics of the underneath without the cover plate?

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Old 1st April 2007, 07:13 PM   #3
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A schematic would help a lot!

It really is pretty much impossible to trouble shoot an amp over the internet. You'll need to do the work yourself, or find someone locally that can help you. All we can do is give you ideas and help you make sense of what you find.

I might start by looking inside the amp to see what is on the back panel that used to get hot but isn't anymore. Beyond that, I would compare the two channels, looking for something different. The voltages at the various tube pins is a place to start (with tubes in place and the amp operating.)

Again, a schematic is pretty much a requirement. The amp is probably not very complicated, so you can draw one up yourself. You'll learn a tremendous amount in the process, which is a good thing.

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Old 1st April 2007, 08:38 PM   #4
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Default inside

thanks for the help so far, I just thought that someone else may have had a similar problem or even recognise the fault straight off. And could guide me to it easily and get the amp sorted. There doesn't seem to be anyone locally who can help me. I could test things but as long as I now what to test, if I have to get a certain part and told where to order it from to get that would be fine. I would like to learn more about these amps, I will probably get a bigger better amp in the distant future when funds allow but I am very happy with this one at the moment im just gutted the one channel has gone. If any one else has more suggestions please contact me.
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Old 1st April 2007, 09:11 PM   #5
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I'm not the tube guru here. But the first thing I would do would be to look at the output trafo. You say it used to get hot, which could indicate undersized iron.

Start with measuring the primary and secondary with the amp NOT connected to the mains. You should get some resistance readings here.
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Old 2nd April 2007, 11:32 AM   #6
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panic over ive found the problem. After another look inside I found a loose resitor. I hadnt seen this on first inspection, totaly missed it, soldered it back up and its fine now. thanks all for all the help anyway.
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