Motorola 9T1- Retrace Blanking?
I'm wrapping up restoration for a Motorola 9T1. I get some retrace lines, sometimes more prominently on the lower half of the picture. I was planning to install a retrace blanking circuit (like the kind popular in the VT-71), but I read in a different thread that the 9T1 (TS-18A chassis variant) addressed that and already had a blanking provision from the factory. The only schematics I've seen are for the TS-18 where G1 of the CRT goes directly to circuit ground. Looking at the actual TS-18A chassis, G1 looks to connect to a resistor/capacitor network on a nearby terminal strip. So, it looks like a similar circuit is there, but I haven't found any documentation highlighting this specific circuit change.
Can anyone verify if this set already incorporated this? If so, are there ways to improve the retrace blanking? With all the extra junk in modern broadcast signals it may just be a case of it not getting rid of all of it. Thanks!
|