type of connector interface is required?
This can be more fun than selecting coax. Here are a couple
of rules of thumb. If you are operating below 300 MHZ, a UHF
connector will generally be satisfactory although it is difficult
to waterproof. Above 300 MHZ, the UHF connector induces VSWR
mismatches. Type "N", TNC and BNC connectors are preferred
at higher frequencies because they maintain a good VSWR. These
connectors are low loss and can handle moderate power (250 Watts)
up to 1 GHz.
If high power and/or low intermodulation distortion is required,
especially where multiple antenna systems are operating in close
proximity, the new large 7-16 DIN connector may be required.
If small size and low power operation from 1-10 GHz is anticipated,
the SMA connector may be preferred.
Regardless of the quality or type of the connector, the potential
exists to introduce noise, signal loss and lower reliability
through every connector break in the trans mission line. An antenna
with an integral jumper or "pigtail" which extends
from the antenna to the feedline on the mast may be preferred.
An antenna with its connector mounted right on the antenna feed
point may be cheaper to buy, but add in the cost of a "jumper" cable,
the signal losses, increased maintenance and you may have to
reevaluate the "value" of a low cost antenna.
The power-handling capability of an antenna is usually a function
of the connector type and the transmission line (if it is an
integral part of the antenna).
You should specify the "average" power that will reach
the antenna. If your transmitter is emitting pulse or peak power,
it is important to inform the antenna supplier the peak power
Technologies, Inc. and the author retain the rights to all intellectual
This information should be used as a guideline
only to help you in the appropriate selection of an antenna.