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Old 13th November 2012, 11:20 PM   #31
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You should really have some speakers connected "before" turning on the amp. See if it will play music. Do you have a multimeter?

jeff
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Old 13th November 2012, 11:29 PM   #32
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You should really have some speakers connected "before" turning on the amp. See if it will play music. Do you have a multimeter?

jeff
Yes jeff i have multimeter
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Old 13th November 2012, 11:48 PM   #33
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Let the amp play some music for 20-30 minutes before you check the bias. There appears to be test points beside each output tube, and an adjustment port on the opposite side. You'll need a small screwdriver (slotted?) to turn the bias pot. With the mutlimeter set on millivolts, insert the probes into the proper test points. You should be getting something around 400 millivolts for each tube. Don't panic if the reading is a little higher or lower, we're assuming that there is a 10 ohm resistor on the cathode of each EL34.
Maybe just take readings for now and post them up here, before adjusting anything. Make sure the amp is not playing any music when you do this.

Don't forget, those big tubes are HOT!

jeff

Last edited by vinylkid58; 13th November 2012 at 11:50 PM.
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Old 13th November 2012, 11:52 PM   #34
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Originally Posted by vinylkid58 View Post
Let the amp play some music for 20-30 minutes before you check the bias. There appears to be test points beside each output tube, and an adjustment port on the opposite side. You'll need a small screwdriver (slotted?) to turn the bias pot. With the mutlimeter set on millivolts, insert the probes into the proper test points. You should be getting something around 400 millivolts for each tube. Don't panic if the reading is a little higher or lower, we're assuming that there is a 10 ohm resistor on the cathode of each EL34.
Maybe just take readings for now and post them up here, before adjusting anything. Make sure the amp is not playing any music when you do this.

Don't forget, those big tubes are HOT!

jeff
Thank you very much i will check voltages tommorow and post them
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Old 14th November 2012, 12:02 AM   #35
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Ok. I guess the amp didn't come with any documentation?

jeff
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Old 14th November 2012, 12:03 AM   #36
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There should be a torx screwdriver included with the amp to adjust bias with.
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Old 14th November 2012, 12:12 AM   #37
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Ok. I guess the amp didn't come with any documentation?

jeff
Yes it comes with a user guid but tell you nothin. I t doesn t say any thing about tube bias just tells you what the controles are for, There is a torx driver and some spare fuses
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Old 14th November 2012, 12:20 AM   #38
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Well, at least you got a screwdriver.

jeff
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Old 14th November 2012, 12:24 AM   #39
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Well, at least you got a screwdriver.

jeff
Yes and some spare fuses but its nice not too badly made and its heavy
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Old 14th November 2012, 09:46 PM   #40
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Hi all my meter is not working for some reason but i have someone comeing tommorow with another meter it says 1.4 v at side of the bias test points is this what i should get from the meter. Will this tell me if i can run the amp on the uk voltage 240 as the amp only has a switch to run 220v. sorry for all the questions
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