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Jon_G4MDC · 10th May 2020, 11:28 am

TP301 is the tuning line of the PLL. The Voltage there will change fairly slowly as you vary the main tuning dial. It will change in steps as you move between 500kHz bands. When out of lock it will probably settle very high or very low in Voltage depending on the reason.

To check the crystals oscillate you do need to be looking at TP03 of the local board. Wish you luck with it.

10th May 2020, 11:28 am	#13
Jon_G4MDC Nonode Join Date: Nov 2015 Location: Welwyn Garden City, Hertfordshire, UK. Posts: 2,015	Re: Yaesu FT221 problem with alignment TP301 is the tuning line of the PLL. The Voltage there will change fairly slowly as you vary the main tuning dial. It will change in steps as you move between 500kHz bands. When out of lock it will probably settle very high or very low in Voltage depending on the reason. To check the crystals oscillate you do need to be looking at TP03 of the local board. Wish you luck with it.