West Mountain Radio CLRspkr ClearSpeech User manual

www.westmountainradio.com
1020 Spring City Drive
Waukesha, WI 53186
262-522-6503
[email protected]
©2012 West Mountain Radio, All rights reserved. All trademarks are
the property of their respective owners.
CLRspkr ClearSpeech®
Digital Signal Processor
Noise Reduction Speaker

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West Mountain Radio Operating Manual
Thank you for choosing the CLRspkr ClearSpeech®Digital Signal
Processor Noise Reduction Speaker. The CLRspkr connects
directly to the radio. The unit is extremely effective in improving
communication clarity. QSO’s will be more enjoyable without
the fatigue of background noise. In many cases, there will be a
noticeable improvement in understanding weaker signals, making
contacts, and general listening.
CLRspkr is ideal for mobile radio operation as noise reduction is
superb due to the Digital Signal Processor (DSP) passing voice and
CW sounds, while attenuating noise, such as atmospheric noise,
hum, hiss, whistles, and static. It effectively removes heterodynes,
ignition noise, lightening crashes, power line noise. The process is
dynamic and changes with the interference and the signal, but the
effect is rewarding. Mobile voice operation is more fun without all
the background noise. The DSP recognizes the intermittent nature
of CW and allows it to pass noise free.
CLRspkr may be mounted in any convenient location. The bracket
permits tilt aiming. The included 6ft. audio cable plugs into the
headphone or mono speaker output on the radio. The unit also
includes a 6ft. power cable with Powerpole connectors that will
plug into a 13.8 volt supply. Extension cables available separately.
CLRspkr is a high-tech, low-cost solution to enhance the audio
quality of communication for ham radio, mobile operation, car and
truck eets, emergency vehicles, and marine radio. The CLRspkr
works well in the home station as well.
Choosing a Mounting Location
The CLRspkr may be mounted in any convenient location. It can
rest on a tabletop or mount to any surface. The bracket has two
holes for mounting with the included screws. The two side knobs
permit tilt aiming. This unit is not weather resistant and suggested
to use in a dry place out of direct sunlight.

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West Mountain Radio Operating Manual
Connections
Audio Input Jack:
Audio input is via the 1/8-inch stereo jack. Use the supplied 6ft.
stereo cable to plug into the headphone output or the mono speaker
output on the radio.
**NOTE for Stereo Cables: The CLRspkr is only one channel. The
stereo jack cable uses only the tip and ground. If using a mono
plug into a stereo jack, one channel gets shorted to ground and may
damage the source. To prevent problems, a stereo cable is supplied.
A stereo jack will use only one channel, but still works with a mono
plug.
Headphone Jack:
The front panel headphone jack works with stereo headphones
only. Both left and right channels receive the same signal
for equal reception in both ears. The high level audio works
ne with modern 8 to 600 ohm headphones. The internal
speaker will still output audio, but can be reduced to silence
with the volume control. The volume control will not adjust the
headphone output.
Power:
The CLRspkr comes with a 6ft. power cable. One end is a 2.1
mm power plug (tip hot) and the other is a pair of Powerole
connectors. RED is for PLUS 13.8 VDC and BLACK is for
Ground.
If using other connectors, just remove the Powerpoles and
connect the white striped wire to PLUS 13.8 VDC and the
other wire to ground.
The CLRspkr is protected from a reverse polarity power
connection.

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West Mountain Radio Operating Manual
A 1-amp 12-volt, wall mount power supply (wall wart) may be
used to power the CLRspkr. The plug required is 5mm OD
with a 2.1 mm pin, and the pin is positive. West Mountain
Radio carries an appropriate accessory power supply for 117
VAC.
Volume Control:
The desired volume level from the loudspeaker may be
controlled with the volume knob on the front of the CLRspkr
unit. Headphone volume is controlled with the volume control
of the radio. NOTE: If using headphones only, turn down the
volume knob on the CLRspkr completely.
Operating
CLRspkr is easy to operate. Turn the Volume knob to power ON.
The LED will start RED and turn to GREEN when the speaker is
properly operating. Adjust the radio’s output volume control to
produce a comfortable listening level. Use the Filter control to adjust
the desired amount of noise reduction The noise will reduce, leaving
the voice/CW signal at a similar volume.
If the incoming audio level is too high the LED will ash orange in
color. Reduce the input just below ashing. Clipping disrupts the
noise reduction circuit.
The front panel “Filtering’ control allows continuous DSP level
adjustment. When turned fully counterclockwise, the DSP is
bypassed. When turned fully clockwise, maximum DSP ltering
is realized. Maximum ltering is rarely needed during use. A
recommended setting is at the 10 - 12 o’clock position for typical HF
channel conditions.

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West Mountain Radio Operating Manual
Noise Reduction Performance
The noise reduction is dynamic and adaptive. It senses the random
character of the voice or CW and permits it to pass through. The
repetitive nature of the noise is sensed and reduced according to the
patented algorithms. Take notice of the DSP battling the difference
between the voice and the noise when both are at equal level and
the noise is constantly varying.
When the signal is CW, its intermittent character is sensed and the
CW is passed through. The noise is attenuated. When the noise
is steady, such as a heterodyne from a 40 meter broadcast station
(carrier whistle), it is attenuated greatly to over 50 dB or about 0.003
times the original value. If the noise is a varying siren, it is greatly
reduced as well, but not as much as a heterodyne.
Transient sounds are greatly reduced, especially if they are repetitious.
The net effect of the Digital Signal Processor is to reduce atmospheric
noise, static, hiss, ignition noise, power line noise, carriers, hum, and
heterodynes, while passing voice and CW signals.
The adaptive nature of the noise reduction is apparent by observing
its convergent time. A single audible tone will vanish in about 1
second. White noise diminishes in 1 to 2 seconds. Typical car noise
and emergency alarms take about 2 seconds to reduce.
Power Amplier
CLRspkr contains a power amplier integrated circuit. It produces
7.5 watts RMS maximum into 8 ohms, when connected to a 13.8
volt DC source. The voltage gain is 46 dB typically. The amplier
has protection from a shorted speaker.

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West Mountain Radio Operating Manual
Specications
Dimensions 5.5 x 4.3 x 2.5 inches
Power Requirements 9 to 16 Vdc; 1.1A typical before onset
of clipping
Audio Input High impedance, 0.01 VAC
Voltage Gain 46 dB
Audio Output Power 7.5 watts RMS maximum into
8 ohms @ 13.8 VDC
Maximum Audio Output Voltage 7.75 Vrms
Input Clipping Level 0.04 volts RMS
Frequency Response 300 Hz to 3400 Hz
Noise Reduction Characteristics Adaptive, single tone greater than 50 dB
Powerpole® is a registered trademark of Anderson Power
Products
ClearSpeech Adaptive Speech Filter
The ClearSpeech Adaptive Speech Filter is an algorithm designed
to lter noise from audio signals containing both speech and noise.
It is implemented in a circuit board containing DSP circuitry and a
small audio power amplier.
Immunity from RF Interference
CLRspkr contains circuitry to reduce interference from the
transmitted radio signal. There are lters on all input wires, and
decoupling capacitors at key points throughout the electronics.
There is a ferrite inductor in series with the positive power lead.
Audio input is via a coupling transformer. The audio input ground is
not connected to the power return. This helps reduce any ground
loops.

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West Mountain Radio Operating Manual
FCC INFORMATION
For a Class B digital device or peripheral, the user instructions
shall include the following or similar statement, placed in a
prominent location in the text of the manual:
Note: This equipment has been tested and found to comply
with the limits for a class B digital device, pursuant to
part 15 of the FCC Rules. These limits are designed to provide
reasonable protection again harmful interference in a
residential installation. This equipment generates, ,uses and can
radiate radio frequency energy, and if not installed and used
in accordance with the guarantee that interference will
not occur in a particular installation. If this equipment does cause
harmful interference to radio or television reception, which can
be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of
the following measures:
• Reorient or relocate the receiving antenna
• Increase the separation between the equipment and
receiver.
• Connect the equipment into an outlet on a circuit
different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV
technician for help.
Modications not expressly approved by the manufacturer could
void the user’s authority to operated equipment under the FCC
Rules.

CLRspkr Warranty
CLRspkr is warranted against failure due to defects in workmanship or
materials for one year after the date of purchase from West Mountain
Radio. Warranty does not cover damage caused by abuse, accident,
misuse, improper or abnormal usage, failure to follow instructions,
improper installation, alteration, lightning, or other incidence of excessive
voltage or current. If failure occurs within this period, return the CLRspkr
or accessory to West Mountain Radio at your shipping expense. The
device or accessory will be repaired or replaced, at our option, without
charge, and returned to you at our shipping expense. Repaired or
replaced items are warranted for the remainder of the original warranty
period. You will be charged for repair or replacement of the CLRspkr or
accessory made after the expiration of the warranty period.
West Mountain Radio shall have no liability or responsibility to customer
or any other person or entity with respect to any liability, loss, or damage
caused directly or indirectly by use or performance of the products or
arising out of any breach of this warranty, including, but not limited to,
any damages resulting from inconvenience, loss of time, data, property,
revenue, or profit, or any indirect, special incidental, or consequential
damages, even if West Mountain Radio has been advised of such damages.
Except as provided herein, West Mountain Radio makes no express
warranties and any implied warranties, including fitness for a particular
purpose, are limited in duration to the stated duration provided herein.
www.westmountainradio.com
1020 Spring City Drive, Waukesha, WI 53186
tel [phone] fax [phone]