42
Personal PA
®
DSP FM Wideband Transmitter
• Ensure the transmitting antenna is not in an unsuitable location. Perhaps the transmitting antenna was installed inside a metal
enclosure or is separated from the reception area by electrically conducting objects. (i.e., steel stud walls, heating ducts,
substantial structural steel, or 2x2 or 2x4 ceiling grid.) In either case, reinstall the antenna according to installation instructions,
locating it outside metal enclosures and away from electrically conducting objects.
• A strong interfering signal may exist. Ensure the transmitter and antenna are correctly installed. Set the transmitter to FULL power
output. If this does not solve the problem, try operating the transmitter on a different channel/frequency.
Users must turn receiver volume controls way up (near maximum) to get enough volume
• Insufficient audio level may be the problem. If so, the audio level indicator will read too low because the audio gain control is set
incorrectly on the transmitter. Correct the Audio Gain control setting by adjusting it until the sound level peaks between 0 and 6
dB. See Figure 7 - Audio Input Level hot buttons.
• It could be that the audio input is not configured for the audio source being used. If not, correct the setting of the Audio Source
control menu. See “Audio Input Settings”.
• Some users may not be helped by this system. Severe hearing loss may require using the system with a telecoil coupler (i.e.,
Neckloop) and personal hearing aid.
• Check your batteries. For non-rechargeable (alkaline) batteries, they may need replaced. If you are using rechargeable batteries,
ensure the batteries are fully charged prior to use.
Users complain of too much noise during soft audio. Dynamic range of music reduced too greatly.
• The Audio Level control may be set too high. This problem is more likely to occur in 2:1 or 1.5:1 Compression modes, but can
also occur in 1:1 Compression mode. To reduce the noise, adjust the Audio Level, carefully noting the Level Indicator. The +6 LED
should light occasionally.
• The transmitter could be set for High Compression (2:1) when Reduced Compression (1.5:1) or No Compression (1:1) would be
more suitable, given the program material. If so, set the Compression Ratio to 1.5:1 or 1:1 and see if this reduces the noise. See
“Audio Settings - Audio Presets - To set up a custom audio preset”.
Buzz in other equipment when transmitter is on or off
• This is not an RF problem. Instead, it is likely caused by incorrect audio connections, a ground loop, or defective equipment. To
remedy, use proper audio wiring practice to make connections shown in Figure 6 (and Figure 4 if needed).
Buzz or other noise in equipment only when transmitter is on
• This is likely an RF–induced disturbance in the other equipment. To remedy, try these steps in order until the buzz is eliminated:
1. Make certain the transmitter chassis is connected to the equipment cabinet rails. Buzz/hum in system may be experienced
when the T45 chassis is insufficiently grounded. In this case, install a ground wire to the T45 chassis and terminate to a
verified ground source.
2. Ensure antenna connections are secure.
3. Set the T45 Transmitter to MEDIUM power output on the RF Power menu choice.
4. Install transmitter at a distance from sensitive equipment.
5. Use a remote antenna (ANT 005 or ANT 024).
6. Make sensitive equipment more immune to RFI/EMI. The manufacturers of your audio equipment may offer application
notes for this purpose. Williams Sound offers a document giving suggestions for improving RF immunity in existing audio
equipment (Technical Bulletin: Buzz Or Hum In The Sound System, FRM 531).
