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previous: danhei Thanks for the schematics.O... -- 7/8/2000 6:53 PM

Re: Ignore those other posts; THIS is the right link

7/8/2000 7:27 PM
jason	Re: Ignore those other posts; THIS is the right link danhei, apparently you don't have a matched quad of tubes and 2 of the 4 are pulling alittle more current they they need. As far as adding a pot to be able to adjust the bias, that's a good thing to have but won't match your tubes for you. To get all four tubes biased right you would probably be better off installing 4 pots so each individual tube could be biased correctly. When using matched sets one pot is fine but with a mis matched set it won't help. Well, I won't say it won't help, you could decrease the current through all the tubes which would probably get rid of the red plates on two tubes but the other two might be biased cold as hell then. Do you have a meter and are you familiar with using one? You could always pull two tubes and run on half power but remember to pull the two outside or the two inside ones. jason

7/8/2000 7:27 PM

jason

Re: Ignore those other posts; THIS is the right link

danhei,
apparently you don't have a matched quad of tubes and 2 of the 4 are pulling alittle more current they they need. As far as adding a pot to be able to adjust the bias, that's a good thing to have but won't match your tubes for you. To get all four tubes biased right you would probably be better off installing 4 pots so each individual tube could be biased correctly. When using matched sets one pot is fine but with a mis matched set it won't help. Well, I won't say it won't help, you could decrease the current through all the tubes which would probably get rid of the red plates on two tubes but the other two might be biased cold as hell then. Do you have a meter and are you familiar with using one?
You could always pull two tubes and run on half power but remember to pull the two outside or the two inside ones.
jason

Replies:

jason One more thing, if you decide to go... -- 7/8/2000 7:41 PM
danhei The pair that glows red was the lef... -- 7/9/2000 8:10 AM