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Author Topic: Carrier Shift & Modulation  (Read 1626 times)
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ki4nr
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« on: December 18, 2021, 02:51:26 PM »

Hi

I'm experimenting with a low level modulator circuit for one of my rice box's. Question on the carrier in general, If you are modulating at 100 percent with perfect symmetry does the carrier shift or is it stable in power?? If you are modulating asymmetrically over 100 percent on positives does it shift in power in that setup. I know wattmeters can respond
differently, so let say a spectrum analyzer is used.

Thanks John
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W7TFO
WTF-OVER in 7 land Dennis
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« Reply #1 on: December 19, 2021, 11:29:49 AM »

Carrier shift can occur due to a design defect, like a soft power supply.

It can also appear via a badly matched load, but shift is not 'part of the game' inherently.

73DG
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Just pacing the Farady cage...
N1BCG
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« Reply #2 on: December 19, 2021, 05:13:24 PM »

Symmetric modulation will always result in minimal carrier shift. Positive peaks over +100% will cause a positive carrier shift. Low PA grid drive or insufficient power supply current will show as negative carrier shift.
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