The PG-A1 is a precision dual-frequency, dual-constellation antenna featuring precision micro center technology and an integrated ground plane.
The CR-3 is a zero centered L1/L2 reference base station antenna mounted on our single-depth choke ring.
Topcon’s CR-4 antenna is an L1/L2 Choke Ring antenna (JPL spec) using a Dorne & Margolin vertical dipole element.