Description
Specifications:
- Tuned specifically for 450-470MHz (high UHF band) for the U.S. Market
- 12″ overall length
- Thread on connector (RFT male)
- Flexible whip with metal base
Tired of breaking your radio antenna?
Click here to see why you should have purchased your BRx7 from us!
Our test of the OEM UHF Antenna (QT400-T provided with the BRx6 and BRx7) shows a center frequency of 438.00MHz with losses rising rapidly above and below that frequency. see graph below.
Peak efficiency is the bottom of the Curve of the Yellow line. See image below.
At 438MHz loss is measured @ 1.36 SWR
At 450MHz loss is measured @ 2.27 SWR
At 470MHz loss is measured @ 5.36 SWR
The effects of this are two fold:
- Loss of effective transmitting power when using a frequency off of antenna center frequency.
- Loss of signal strength when trying to receive a frequency off center
You will experience this as less than ideal range between Base and Rover, and find
that you encounter MORE interference from nearby sources.
By comparison our Exclusive Aftermarket UHF antennas are tuned for a center frequency of 462MHz.
At 462MHz loss is measured @ 1.41 SWR
At 450MHz loss is measured @ 1.74 SWR
At 470MHz loss is measured @ 1.80 SWR
This puts the “sweet spot” of efficiency of our Aftermarket Antenna right in the middle of the U.S. Commercial UHF band (450-470MHz).
Why is this important?
EFFICIENCY of radio transmision and Reception which directly affect RTK Range and performance.
Why are the receivers shipped with antennas tuned for 438MHz?
- Only the U.S. market operates in the high UHF band (450-470MHz). Most other countries use the lower UHF band (400-440MHz). Since the rest of the world is a larger market we suspect they ship antennas that meet the needs of their largest user base.
ONLY Carlson Survey Supply is aware of this and that is why we supply our Aftermarket antennas with ALL of our BRx7 Base-Rover Packages so our customers get the BEST PERFORMANCE POSSIBLE!
