Troubleshooting; Specifications And Features - Lectrosonics M175 Instruction Manual

M175

Troubleshooting

Before going through the following chart, be sure that you have a good battery in the transmitter. It is important that
you follow these steps in the sequence listed.
Symptom:
Transmitter battery LED off
Receiver RF lamp off
No sound and receiver
mod level LEDs are off
No sound but receiver
mod level LEDs are on
Distorted sound
Hiss and noise -- Audible dropouts
Excessinve feedback

Specifications and Features

Operating frequencies:
RF Power Output:
Deviation:
Spurious Radiation:
Frequency Stability:
Equivalent Input Noise:
Input Sensitivity:
Input Compressor:
Electret Bias:
Antenna:
Input Jacks:
6
Possible Cause:
1) Unit turned off. Check front panel on/off slide switch.
2) Battery is inserted backwards.
3) Battery is dead.
1) Transmitter not turned on.
2) Transmitter battery is dead.
3) Receiver antenna missing or improperly positioned.
4) Transmitter and receiver not on same frequency.
Check labels on transmitter and receiver.
5) Operating range is too great.
1) Transmitter audio muted (M175-LS only)
2) Microphone or input cable defective.
1) Receiver audio is muted. Refer to receiver manual.
2) Receiver audio output is disconnected or cable is defective
or mis-wired.
3) Sound system or recorder input is turned down.
1) Transmitter gain (audio level) is too high. Speak or sing into the
transmitter and check mod level lamps on the receiver
(see Operating Instructions.)
2) Receiver output may be mis-matched with the sound system
or recorder input.
3) Excessive wind noise or breath "pops."
1) Transmitter gain (audio level) too low.
2) Receiver antenna missing or obstructed.
3) Operating range too great.
1) Transmitter gain (audio level) too high. Check gain adjustment
and/or reduce receiver output level (see Operating Instructions.)
2) Transmitter too close to speaker system.
3) Move transmitter closer to the user's mouth.
150 to 216 MHz
50 mW
±15kHz
50dB below carrier
±0.005%
-123dB
8mV to 1.6V for full modulation
Soft Compressor; 12dB range
+5 Volt DC (positive bias)
Input cord or microphone body
Twist-lock micro for electret
microphones
Battery Indicator:
Battery Life:
Controls:
Size:
Weight:
FCC ID:
Emission designator:
Specifications subject to change without notice.
LED indicates battery condition
Approximately 15 hours
Power on/off slide switch
Recessed audio gain control
Mute on/off toggle switch (M175-LS
only)
1.3 x 2.35 x 3.7 inches
6.6 ozs with battery and microphone
DBZM175 (150 to 172 MHz)
DBZM175A (174 to 216 MHz)
58K0F3E
LECTROSONICS, INC.