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another tip, if the horz hold is a bit touchy (it was much better after the tube fix, about 3/4 turn range vs 1/8 range, it was still not right.
I checked the resistor across the horz hold coil, a 68k, I assume it damps out the coil, making it less peaky, so had to remove it from the circuit to check, sure enough 381k, so that one got replaced. While I was there I checked a 270k power resistor, it was about 330k, but it was a 5% so I changed it as well. two changes were noted:
MUCH easier to set hold you can turn it several times and still stay locked in.
Drive bar was gone even a the lowest drive setting. (before a drive bar was present but could be dialed out with the drive control pot). HOtube current is up just a tad to about 175ma with drive set to max.
for fun I am going to replace that drifted power resistor and see I can get the drive bar back.
I am pretty sure the 68k damping resistor will account for the better hold control, but maybe it also altered the drive wave form (and subsequent need to adjust out the drive bar).
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