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Old 10-18-2024, 09:04 AM
Chris K Chris K is offline
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Join Date: Jun 2022
Posts: 1,505
Do you understand what you are doing by clipping in place the resistors? It is to eliminate the resonance of the stagger tuned coils so that the remainder of the video IF strip is just an untuned amplifier. This is so you can see independently the tuner over coupled transformer link frequency response when you sweep it. You must try and understand the process so so will be better able to identify and rectify any problems.

So what is it I'm stopping by attaching the resistors? Is it the resonant, in circuit coils or the trap coils? I sorta get the statement this makes the video IF stages an untuned amplifier but the statement "This is so you can see independently the tuner over coupled transformer link frequency response when you sweep it"is making my head spin. So when I sweep the input signal symmetrically 10mc with 25mc as the center frequency (from 20-30mc) and pick it up on the scope at the end of its travel through a detuned IF series of stages, I'll see the full bandwidth signal out at the end? If so why is that important to see and what then am I looking for to adjust?
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