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#76
07-08-2004, 09:29 AM
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LOL. it is. Its driving me nutso.
ALL OF THE PAPER CAPS have been replaced. ALL OF THEM. Yes, there NOS. There not from allied, I DO NOT want to buy from allied, they can shove thier 25 dolla minimum up thier a** That 100pf has to be good, becuase it has no deflection at all, when I pull it out of circuit. Last edited by mbates14; 07-08-2004 at 09:34 AM. 
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#78
07-08-2004, 10:28 AM
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uhhh.
I cant check the waveform if there is no HV there is none. Heres why: The vert output gets its B+ from the HV supply. Any ideas? id say the .005 are breaking down under HV. I did switch them, the picture didnt change. There is also a big huge aluminum can that is rated .005 at 6000vdc I havent changed yet, because I dont have a replacement for it yet. according to the schematic, it looks like a bypass cap, it has to work or there wouldnt be any HV. Last edited by mbates14; 07-08-2004 at 10:30 AM.
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#79
07-08-2004, 10:55 AM
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I replaced some out of tolerance 4.7meg resistors on the deflection plates.
one of the 4.7meg resistors was around 8.6meg in the vertical stage. I replaced that. another 4.7megohm in the horizontal stage was about 30megohms. Does that look out of tolerance? LOL that solved the focus problem, and the picture is better centered. but no result on the linerity.
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#81
07-08-2004, 01:42 PM
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I have a question, What actually inverts the waveform? I know that the waveform on the first plate is acutally not inverted. It gets inverted by the time it hits the second grid.
What inverts it? whatever part is responsible for inverting it may be a little bit weak. Imma going to head over to ratshak to pick up packs of 5, anything greater than 1megohm. that way if I run into somethi8ng, I will have the resistors on hand. I might just go ahead and replace those 10 megohm resistors anyway. After that, there wont be any resistors left to replace in the vertical section, other than caps.
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#82
07-08-2004, 02:10 PM
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When you supply an ac waveform to a grid of a triode, as the voltage goes more positive the output on the plate goes more negative. So as the output of one section of the vertical output triode is fed back into the grid of the second section, its output on the plate is the inverse.
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#84
07-08-2004, 03:55 PM
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If you look VERY VERY closely, between the first and second inverted wave, the wave of course, isnt very strong as the first one, BUT you notice the ramp on the sawtooth wave for the first one is streight. Its slightly curved on the inverted one.
Any ideas?
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#86
07-08-2004, 04:46 PM
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I'm sure the photos of the two traces are from the two grids. The first section of the tube has the grid connected to the oscillator. The waveform is amplified and inverted in the first section. A portion of the signal from the first plate (inverted as compared to the grid of that section) is fed to the grid of the second section. That is the purpose of the C57, C142, R117, etc. Those components attenuate the signal from the plate of the first section by an amount equal to the gain of the first section, so thr proper amplitude is fed to the grid of the second section.
The second section of the tube amplifies and inverts that waveform. So, the waveforms supplied to the CRT defectin plates are inverted. The inversion process take place as Steve K describes it.
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#89
07-09-2004, 06:01 PM
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Are you sure about this? could it be an electrolytic?
I haven't seen any 6000v caps in metal cans. BTW, your new caps are on their way as of today. Quote:
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Linear Mode
