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I think I used 3.9 mH for 6.8. I did buy an assortment ane tested each one for inductance using one of those yellow meters anf for self-resonance using a frequency synthesizer, a 1 megohm scope probe, feeding the signal in through a 1 pF capacitor. I used my 5-spice simulator in the actual circuit and tried the best two
in the actual set, sweeping them (with the horizontal system fully disabled as the yoke was not connected.) I used the best looking sweeps. All looked fine when tried on actual pictures except the Q one. That one I tried by mounting the chassis behind the set and trying coils and different values oif the nominally 27 pF cap from the Q demod to ground. It a compormise between the best looking Q channel response and the problem that the best response looks terrible because its much too early ... it would need less delay in the Y delay line and the I filter, which has intentional delay in it . I have actual photos of the restult on +-I and +-Q bars posted on an earlier thread here. I will repost here. Note that the time error is obvious here ... but not on program material. Note that there is an orange bar from crosstalk on green to violet but the corresponding bar on green to violet looks more like luminance. Except for the black and white bars, Y is constant. Note that th I channel looks really good.
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