Quote:
Originally Posted by andy
Start by checking the resistors....
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Quote:
Originally Posted by sampson159
...i had a similar issue with my ctc 15.there is a resistor off the linearity control that may solve this.mine was almost identical.also a cap in the vertical by the output tube.good luck and that is a good looking roundie.keep us posted on this.
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You guys called it. R136 is a dropping resistor that takes the 440v supply from the top of the vertical centering control and drops it to supply the vertical height and grid voltage through a voltage divider network. its supposed to be 150k - which it initially tested in circuit. However I was apparently measuring the total resistance of the circuit. When i pulled the resistor it turned out to be damn near 2 meg!
I discovered this when tracing back the voltage from the grids of the oscillator/output tube. when I got to R136 it had over 400 volts across it. If it were a 150k it would be on fire - so i figured it had gone way up in value. Pull it out of circuit - sure enough.....
I'll get a new resistor in there. Should take care of the problem.