17
Feedback
Avoid acoustic feedback (howling or screeching) by taking care in selecting pA
volume, transmitter location and speaker placement.
please also note the pickup pattern characteristics of the microphone selected.
Unidirectional microphones are more resistant to feedback. However, they pick up
sound sources best that are directly in front of the microphone. Also, mics that are
farther from the sound source (such as a handheld) require more acoustic gain and
thus are also more prone to feedback than close-source mics.
No or Low Audio
If you are not getting audio through the system, carefully re-check all setups.
Especially note that the receiver and transmitter must be set to operate on the same
RF channel. Also confirm that the transmitter’s AUDIO MUTE (36, 40) is not in the
OFF position. The receiver’s UNBALANCED LINE OUT (19) is adjustable so make
sure the VOLUME CONTROL (21) is set properly.
RF Interference and Finding Open Channels
The FCC mandates the following information be provided to all end users of this
equipment:
Consumer Alert
Most users do not need a license to operate this wireless microphone system.
Nevertheless, operating this microphone system without a license is subject to certain
restrictions: the system may not cause harmful interference; it must operate at a low
power level (not in excess of 50mW); and it has no protection from interference
received from any other device. purchasers should also be aware that the FCC is
currently evaluating use of wireless microphone systems, and these rules are subject
to change.
For more information, call the FCC at 1-888-CALL-FCC (TTy: 1-888-TELL-FCC)
or visit www.fcc.gov/cgb/consumerfacts/wirelessmic_factsheet.html.
If you encounter slight receiving interference when the transmitter is far from the
receiver (from other than an operating Tv station on the same frequency), it can
often be overcome by adjusting the receiver‘s MUTE LEVEL/SQUELCH (13)—see
Adjusting the Mute Level / RFSquelch.
If receiving interference on a selected channel with the transmitter off, or if you en-
counter interferences in operating multiple U-800 systems simultaneously at the same
location see: “6. Selecting Group/Channel, IR Programming and Simul-
taneous Multichannel Operation” for proper procedures for reprogramming
system(s) for open channels.
7. CAUTIONS AND TROUbLESHOOTING
