One reason may be difference in loction of AirNav and NooElec antennas. Try changing location of AirNav antenna, as close to NooElec location as possible. Also try various other location in the Balcony.
The other reason may be difference in length and quality of coax cables of the two antennas.
Nooelec antenna "RaTLSnake M6 v2" has 2 meters coax cable type RG58, which has attenuation (signal loss) = 0.7 dB per meter
The AirNav 1090 Antenna has 30 feet (10 meters) cable (unknown specifications, unknown attenuation).
Due to longer coax cable length (10m) compared to short length (2m) and unknown specs of coax, the signal strength arriving at dongle from AirNav antenna possibly has less strength than signal arriving from NooElec antenna, resulting in reduction of range.
Try increasing gain setting of the dongle. Which decoder software you are using, dump1090-rb, or dump1090-fa, or readsb?