Campbell Scientific RF401-series and RF430-series Spread Spectrum Data Radios/Modems - Manual (Page 107)

Appendix K. RF401/RF411 Pass/Fail Tests
TESTING ANTENNAS
After setting up the terminal program and verifying the integrity of the COM
port, serial cable, and RF401/RF411s, you are ready to test an RF401/RF411
antenna. Prepare to test an antenna by:
• Orienting RF401/RF411s so that the antenna connectors are on top
• Fastening RF401/RF411s to cardboard boxes or other non-metallic
structures maintaining antenna connectors 20 inches above the floor.
(1) TESTING ¼ Wave Antenna
(a) Connect 12V power to base RF401/RF411 and remote RF401/RF411.
We recommend AC adapter Item # 15966 or a Field Power Cable
Item # 14291 connected to a 12V battery pack or 12V power supply. 1
(b) Choose an open area free of large 2 metal objects within 10 feet of the
RF401/RF411s (can be indoors or outdoors).
(c) Attach a 1/4 wave omni antenna (Item # 14310) to base
RF401/RF411
(d) Set up remote RF401/RF411 with NO antenna
(e) Separate RF401/RF411s by 5 feet
(f) Type 8 groups of 5 characters on the terminal (aaaaabbbbbccccc etc.)
(g) You should receive 100% of the characters
(h) With bad or missing ¼ wave OMNI antenna you should get few to no
characters echoed back.
1 Be careful to not exceed maximum supply voltage of 16 VDC to RF401/RF411. Use
“quiet” power supply without noise or hum (a 12V lead-acid battery is fine, if no trickle
charger is attached during the tests).
2 Examples of “large metal objects”: a steel filing cabinet; steel trim on cubicle
dividers; or steel shelving. Especially avoid such metal objects facing the
RF401/RF411s broadside. The idea is to avoid significant reflected signals because
they can add to or subtract from the direct wave signal making test results vary a lot
according to exact location. A fully absorbent rf environment with no reflections would
be ideal.
(2) TESTING YAGI or COLLINEAR ANTENNA
(a) Connect 12V power to base RF401/RF411 and remote RF401/RF411.
We recommend AC adapter Item # 15966 or a Field Power Cable
Item # 14291 connected to a 12V battery pack or 12V power supply
(see footnote 1 above).
(b) Choose an open area to conduct the tests (see footnote 2 above).
(c) Attach the yagi or collinear antenna being tested to base
RF401/RF411
(i) A yagi can be mounted on a microphone stand or similar (metal,
wood or PVC ok). Orient antenna elements vertically as shown
in figure below and adjust height so the bottoms of the elements
are 20 inches above floor. Aim yagi at remote RF401/RF411.
K-5