Rf Interference - SABINE SWM7000 Application And Troubleshooting Manual

1.4.15. We have successfully solved dropout problems using this technique in a very
large hall using 77 meter cable runs. Please note that high-gain extension
antennas are required to overcome the loss of the splitter and please note that you
must preserve diversity. The splitter we recommend can be found here:
http://www.hyperlinktech.com/web/signal_splitters_2400_2way.php
1.4.16. You can also daisy-chain two antennas on one cable length by moving the
splitter from the ADA to the first antenna.
1.4.17. Testing Your Antenna System. It only takes a few minutes to test your
extension antennas, antenna cabling, and antenna distribution amp. Eliminate
them from the system by simply placing a receiver on the stage with the dipole
antennas. Check your RF performance (Use powered speakers patched directly to
the receiver if you cannot connect to your sound system. If your dropouts go away,
you know the problem is with the antenna system.

2. RF Interference.

2.1. Outside sources of RF in the 2.4 GHz band can interfere with your wireless
microphone system if the outside source is strong compared to the transmitter's signal.
Interference can cause dropouts or ticking and sputtering sounds in the audio. Possible
sources of 2.4 GHz interference include wireless LANs, some cordless phone,
microwave ovens, cordless security systems, wireless system control panels, such as,
Crestron and AMX, etc.
If you use the wireless systems in a room with a WiFi device close to the receiver, the
systems will work perfectly when the transmitters are close to the receiver. But as they
walk away, the transmitter signal level may eventually drop below the WiFi signal level
causing the system to squelch. The easiest way to overcome this problem is to
reallocate the WiFi to higher frequencies and leave the lower channels for the Sabine
system. Alternatively move the WiFi and the receiver away from each other. If these
solutions are not practical, we will soon offer directional antennas that reject off axis
WiFi signals.
2.2. 2.4 GHz transmitters signal strengths are limited by governmental regulations. If the
source of the interference is 50 feet or so farther from the antenna than the microphone,
you will rarely hear interference.
2.3. The best way to locate clear channels and avoid outside interference is to turn off the
Sabine mics and then run the scan function in Sabine Remote. Turn on all known
possible sources of RF interference in your area. Is there a microwave oven nearby? If
so, put a cup of water in it and run it while you scan. The scanner lets you block out
channels that have interference.
2.4. The next best way to locate clear channels If you cannot run a scan but you hear
interference, change to different RF channels. Move at least ten channels up or down
to avoid a single spread-spectrum source.
2.5. Generally it is best to clump the system's channels close together at the low or
high end of the spectrum, i.e. channels 1, 2,3,4,5 or channels 65, 66, 67, 68. If there
Sabine Wireless: Application and Troubleshooting Guide 5 of 12