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Audio Input
Impedance
Terminated with approximately 8 Ohm load
Minimum input level
80 to 500 mV (for correct working levels)
Maximum
6 Watts (maximum withstand)
Audio output
Impedance
Internal Speaker 8 Ohms (Nominal)
External speaker/phones 4 Ohms (minimum)
Level
10
Watts
R.M.S.
nominal (with 12V DC. supply)
Controls
Single
power/function
button
Volume control
Indications
Power
ON/
FUNCTION
AUDIO LEVEL
Connections
2.1mm
DC
power
jack
3.5 mm mono, external speaker/headset socket
Integral 2M long 3.5mm mono jack plug lead (audio input)
9. Troubleshooting/FAQs
Speaker doesn’t work at all, no sound from the speaker:
•
Check that the power connector on your power supply is suitable for the power
socket on the speaker (2.1mm, centre positive). Check the fuse. Check
connections to your power supply.
•
Check that you have switched your radio communication equipment on and that you
have a signal for the speaker to process. To verify this, remove the audio connector
from the external speaker socket on your equipment.
•
Check that the AUDIO LEVEL LED is illuminating green.
The speaker works but the noise cancellation doesn’t appear to improve the audio
quality of the signal:
•
Check the filter is switched on and increase the level to see if this makes any
difference.
•
Check that the AUDIO LEVEL LED is illuminating green.
4. Troubleshooting/FAQs
The volume from the speaker is low and cannot be increased:
•
The speaker is designed to work with external speaker sockets of radio
communications equipment, and although it will work with some earphone and
headphone sockets, there may be occasions where the signal output from these is
not enough for the speaker electronics to process the signal effectively. bhi have
another product that will work with these levels of signal, the NEIM1031MKII (DSP
Noise Eliminating In-line Module). Please contact bhi for more information.
Sometimes there is a short delay before the noise cancellation is active:
•
This is due to the time the DSP takes to start processing the signals. This gives you
the opportunity to check that the DSP is not taking out any detail from the signal.
Sometimes I can hear a processing sound in the speaker when no signal is present:
•
This is normal and is caused by the DSP processor. When a signal is applied you
should not be able to hear this in the speaker.
