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That's some good info right there. Modern radios can have too much gain with objectionable noise if they are not properly aligned. I've seen an IF strip in one rig that was tampered with. Some of the transformer slugs were obviously backed out of the coil form too far with much of the slug exposed.

I expected to hook the signal generator up and find very poor sensitivity based on my visual inspection. To my surprise it was very sensitive and very noisy. It appeared to be about twice as sensitive as its specs but nearly 10 times more inside noise that made the extra sensitivity useless because weak signals couldn't overcome the noise.

Some transformers may have more than one tuning peak. Good service manuals will tell you which peak is the correct one to tune for. It's almost always the one with the slug deeper in the coil form.

Other radios may have an internal IF gain control that must be adjusted after alignment. This insures the stage is not under driven and producing less gain or over driven and producing distortion or noise.

<blockquote data-quote="Shockwave" data-source="post: 442652" data-attributes="member: 10882">That&#039;s some good info right there. Modern radios can have too much gain with objectionable noise if they are not properly aligned. I&#039;ve seen an IF strip in one rig that was tampered with. Some of the transformer slugs were obviously backed out of the coil form too far with much of the slug exposed. I expected to hook the signal generator up and find very poor sensitivity based on my visual inspection. To my surprise it was very sensitive and very noisy. It appeared to be about twice as sensitive as its specs but nearly 10 times more inside noise that made the extra sensitivity useless because weak signals couldn&#039;t overcome the noise.Some transformers may have more than one tuning peak. Good service manuals will tell you which peak is the correct one to tune for. It&#039;s almost always the one with the slug deeper in the coil form.Other radios may have an internal IF gain control that must be adjusted after alignment. This insures the stage is not under driven and producing less gain or over driven and producing distortion or noise.</blockquote>

[QUOTE="Shockwave, post: 442652, member: 10882"] That's some good info right there. Modern radios can have too much gain with objectionable noise if they are not properly aligned. I've seen an IF strip in one rig that was tampered with. Some of the transformer slugs were obviously backed out of the coil form too far with much of the slug exposed. I expected to hook the signal generator up and find very poor sensitivity based on my visual inspection. To my surprise it was very sensitive and very noisy. It appeared to be about twice as sensitive as its specs but nearly 10 times more inside noise that made the extra sensitivity useless because weak signals couldn't overcome the noise. Some transformers may have more than one tuning peak. Good service manuals will tell you which peak is the correct one to tune for. It's almost always the one with the slug deeper in the coil form. Other radios may have an internal IF gain control that must be adjusted after alignment. This insures the stage is not under driven and producing less gain or over driven and producing distortion or noise. [/QUOTE]

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