Off Designed-Frequency Behavior of 2 Types of Antennas

FlightAware ADS-B Flight Tracking
65

I did run analyzer with insulated and bare whips, both 67 mm.
The test proved that the analysis of Oliver (obj) is right.
Both gave same SWR (1.4) and both were resonant at same frequency (1090 Mhz).
Please see photos below:

Whips
72mm insulated, 67mm insulated, 67mm bare

Insulated Whip 67 mm

576×1024 83.2 KB

Bare Whip 67 mm

576×1024 78.1 KB

Bare Whip 67 mm

576×1024 80 KB