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Originally Posted by Bill R
I checked my field service guide and it shows the resistor connected to the grid of the 6cg7. What you have in blue. The voltage on the grid is -88 volts.
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Thank you very much for that information. Yellow is the layout of my service manuals here (only as pdf-file) and blue is the actual layout of the printed assembly here on the chassis. Note:I have copy and drawn here the blue parts into the photo of the schematics! In this ctc-5 the printed assembly PW600 was changed. This change was not documented in my service guide.
Yesterday I have tested the 6CB5. With 40 percent it was at the lower end of the scale. I have renewed it. Now I read -24v at the grid of the 6CB5, horizontal output current now is 190ma (with 114v ac) and 170mA (with 105v ac, for comparison see my posting of 02-12-2005 12:16 AM). Picture width is wider than the screen in the middle position of the width switch. Flyback is very warm, but not hot after one hour.
At first glance all seems OK now. But I think, -24v at grid of 6CB5 is still not enough. There is too much d.c. in the horizontal output unit. It should be -40v. When I get a new damper I will change it too (usually I change only horizontal output tube and damper together).
At the anode, pin 6 of the 6CG7 (horizontal oscillator, V601), I read 140v, should be 235v according to schematics. At the grid (pin 7 of 6CG7) I read -40v, should be -88v according to the reading in your field service guide. The 6CG7 seems not ok, I have found a short between heating and kathode. But kathode here is connected with the ground of the chassis.