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Old 21st March 2013, 02:09 PM   #2741
stajo is online now stajo  Sweden
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Try both channels, same values on everything on each channel after split
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Old 21st March 2013, 02:11 PM   #2742
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So other 4k75 & other 220uF for the new rail for the 2nd tube, right?
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Old 21st March 2013, 02:23 PM   #2743
stajo is online now stajo  Sweden
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Yes. To try if we get same values.
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Old 21st March 2013, 02:32 PM   #2744
stajo is online now stajo  Sweden
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Quote:
Originally Posted by massimo View Post
Looks good. 136V on plate, 9.59V on cathode is basically the same working point as per Andy's schem (138 and 10).
Yea but where does 29 mA current go?
http://www.r-type.org/pdfs/26-1.pdf
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Old 21st March 2013, 02:37 PM   #2745
massimo is offline massimo  Italy
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I got lost about the anode resistor thus I couldn't calculate the I
(the link doesen't work)
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Old 21st March 2013, 02:41 PM   #2746
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137V plate
0V across grid stopper
9,86V cathode positive to ground
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Old 21st March 2013, 02:42 PM   #2747
iko is offline iko  Canada
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At this point it looks like it almost works. Here's roughly how it should be.
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File Type: jpg IMG_20130321_090838.jpg (87.5 KB, 135 views)
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Old 21st March 2013, 02:45 PM   #2748
stajo is online now stajo  Sweden
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Quote:
Originally Posted by merlin el mago View Post
137V plate
0V across grid stopper
9,86V cathode positive to ground
Exact values for both channels? So what voltage do you now have over each 4k75?
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Old 21st March 2013, 02:45 PM   #2749
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Iko I don't have connected the 100R before the OPT, do you want that I connect to see if the voltage drop is 0,5-01V? also I don't have connect the 100nF input cap, is necessary?
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Old 21st March 2013, 02:48 PM   #2750
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Quote:
Originally Posted by merlin el mago View Post
137V plate
0V across grid stopper
9,86V cathode positive to ground
Quote:
Originally Posted by stajo View Post
Exact values for both channels? So what voltage do you now have over each 4k75?
Right channel
137V plate
0V across grid stopper
9,86V cathode positive to ground
over 4k75 64,4V

Left
125V plate
0V across grid stopper
9,47V cathode positive to ground
over 4k75 73,4V

Last edited by merlin el mago; 21st March 2013 at 02:52 PM.
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