Quote:
Originally Posted by old_coot88
I've seen cases of the horiz. being miles off-frequency, but never saw (or heard of) it causing the fly to put out 'too much' juice. The HV is not the product of the sweep frequency but of the fast "fly-back" spike of the sawtooth.
Just wondering if maybe the second 1X2 could be bad. This'd be one case where it would be handy to have a SS stick rectifier to sub in there. oc
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Dug out this Zenith { Chassis14Z33 } from the B@W room and connected the HV probe to the to the anode of the CRT. I picked this set because it has a vary stable tube horizontal oscillator/output circuit and a coil for the horizontal hold control. Turned on the set and let it warm up, With a normal picture the HV reads 19kv on the probe. Then I turned the horizontal coil one and a half turns counter clockwise. The picture went out of sync and the HV went up to 22 KV. What else was interesting is when I turned the coil one more rotation counter clockwise the HV went back down to 19KV and the picture was a horizontal mess. This proves that there is a direct connection between the horizontal oscillator and the high voltage. I guess I just do not know how to explain the problem properly. All I know is I have seen this type of problem before in the 1950"s set's and they are hard to track down. Also the horizontal circuits are not as stable in a 50's set as the horizontal circuit in a 1969 zenith.
I am not a big fan on installing solid state diodes in place of a diode tube. I tried it once with a ctc 15 chassis damper tube and it increased the horizontal output tube current. Plus it looks funny on the chassis.
Ed