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Hi folks! The ctc-5 is working again!
Beside the defect 6cb5, which I have replaced with the old 6cg5, I found a defect at the sine coil. Because of the extreme positive voltage at grid of the 6cb5 this voltage is linked to the grid of the 6cg7 too (via R165). The high current of the 6cg7 had burned out the sine coil. I found an interuption at one feet of the coil which could be soldered carefully.
For testing the chassis without crt and horizontal output unit I inserted a 4K 50watts resistor between chassis ground and +385v and used the 105v ac source to get clear +385v.
Without 385v d.v. at the horizontal output unit, I have now the correct -89v at grid of 6cg7 and -39v at grid of 6cb5 !!
Then I inserted the chassis into the set, testmeter at horizontal output current and grid of 6cb5, high voltage probe. The results: horizontal output current is 208ma, picture has full horizontal width, even in the smallest switch position.
The next readings: -37.8v at the grid of 6cb5 !! 19.25kv with the hv probe.
Some remarks: R608 has 103K. Plate voltage on pin 1 of the 6cg7 is 293v.
While renewing the resistors I found that R603 has 90K, should be 150K I have soldered a 150K resistor instead of 90K!
The other resistors had no out-of-tolerance values but some of them were crumbly, they broke while removing.
In the next days I will watch the set and its flyback how warm or hot it will be after 15, 30, 45 and 60 minutes.
Thank you for all your support and patience with me.
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