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Jon_G4MDC · 12th May 2020, 9:29 am

It's good there's tone only on one side of zero beat with an SSB radio. It means your unwanted sideband suppression is good.

Zero beat is the position where the tone is zero frequency. Sometimes you can just hear a slow flutter in the noise - that's a beat of just a few Hz or less.

On a 221 the dial calibration of zero beat changes between USB and LSB. Thats why the button below and left of tuning dial. If you haven't found it yet it's a clutch which grips the circular scale to adjust cal after mode changes. Calibrate it on USB since LSB is almost never used except with some transverters etc. On AM and FM an error of 1kHz in the cal is hardly serious - probably leave it alone on those modes. I do.

12th May 2020, 9:29 am	#16
Jon_G4MDC Nonode Join Date: Nov 2015 Location: Welwyn Garden City, Hertfordshire, UK. Posts: 2,015	Re: Yaesu FT221 problem with alignment It's good there's tone only on one side of zero beat with an SSB radio. It means your unwanted sideband suppression is good. Zero beat is the position where the tone is zero frequency. Sometimes you can just hear a slow flutter in the noise - that's a beat of just a few Hz or less. On a 221 the dial calibration of zero beat changes between USB and LSB. Thats why the button below and left of tuning dial. If you haven't found it yet it's a clutch which grips the circular scale to adjust cal after mode changes. Calibrate it on USB since LSB is almost never used except with some transverters etc. On AM and FM an error of 1kHz in the cal is hardly serious - probably leave it alone on those modes. I do. Last edited by Jon_G4MDC; 12th May 2020 at 9:35 am.