Up to four Tetra transceivers can share one common antenna, via a four-channel hybrid ring combiner which allows parallel operation the receivers with the highest possible decoupling (isolation). The combiner is from a range of antenna-related products from Procom. It can be adjusted to optimize isolation, and – depending on the SWR of the antenna – up to –50 dB is achievable at the centre frequency. Power handling is up to 50?W per channel.

Among Procom’s series of multi-band vehicle antennas is a colinear which provides Tetra, GPS, FM broadcast, 2m (167·5–174 MHz) and 4m (74·2–87·5 MHz) band coverage. The whip antenna (of glass fibre with a copper winding) is mounted on top of the GPS patch antenna mount, which also includes a built-in amplifier. Power is supplied via the cable. The whip is easily removable for the car-wash.

•  procom.dk">www.procom.dk