Is your leaf blower possibly electric? Looks to me like it could be interference from a nearby electric motor.
Mel Asberry, DAR since the last century. Over 1,000 certifications accomplished.
EAA Flight Advisor/Tech Counselor, Friend of the RV-1
Recipient of Tony Bingelis Award and Wright Brothers Master Pilot Award
USAF Vet, High School E-LSA Project Mentor.
RV-6 Flying since 1993 (sold)