Hamilton Buhl ALS700 Assistive Listening System Instruction Manual

: June 9, 2024
: Hamilton Buhl

Hamilton Buhl ALS700 Assistive Listening System

Please Read This Instruction Manual Before Operating This Unit and Retain for Future Reference

SAFETY CAUTIONS

This product is designed to amplify audio to a high volume level which could potentially cause hearing damage if used improperly. To protect your hearing, make sure the volume is turned down before putting on the ear speaker or headphones. Then adjust the volume up to the minimum setting required to hear clearly. Do not allow children or other unauthorized individuals to have access to this product without supervision.
Stop using immediately if any liquid falls into the unit.
If the unit is not to be used for a long period of time, please disconnect all power sources, remove all batteries from the receivers. Do not unplug the power adapter of transmitter by pulling the cord.
Place the transmitter on a flat/even surface and in an area with proper ventilation. Do not cover the unit with a cloth or place on a carpeted surface. Only place the transmitter on a flat, even surface.
Do not use the unit in extremely hot, cold, dusty or humid environments.
Humid environments can cause condensation to form inside the unit. If this occurs, remove all power sources and allow the unit to sit at room temperature for 1-2 hours prior to use, to allow condensation to dissipate.

COMPLIANCE WITH FCC REGULATIONS

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 against 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 instructions, may cause harmful interference to radio communications. However, there is no 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. To assure continued compliance, any changes or modifications not expressly approved by the party responsible for compliance, could void the user’s authority to operate this equipment. (Example: use only shielded interface cables when connecting to computer or peripheral devices).

This equipment complies with Part 15 of the FCC Rules. Operation is subject to the following twoconditions:

This device may not cause harmful interference, and
This device must accept any interference received, including interference that may cause undesired operation.

RF Warning Statement

The device has been evaluated to meet general RF exposure requirements.
The device can be used in portable exposure condition without restrictions.

Included with This System

(1) ALSM700 Dual Channel Transmitter
(6) ALSR700 Dual Channel Receivers
(6) ASLB700 Mono Earbuds
(1) Power Adapter
(1) Instruction Manual
(18) “AAA” Batteries
(1) Carrying Case

ALSM700 Transmitter Controls

REAR PANEL

FRONT PANEL

Line In Jack
DC 5V Jack
Microphone Input
Antenna
Power On/Off Switch
Power Indicator
Signal Indicator
CH1 and CH2 Indicators
Channel Selection Button
Volume Control Knob
Channel Selection Button
Phone Jack
CH1 Indicator
CH2 Indicator
Gain Control Knob
Power On/Off Switch
Belt Clip
Battery Compartment

ALSM700 Transmitter

Powering the Transmitter

NOTE: Use only with the supplied power adapter.

Insert the smaller end of the adapter plug to the back of the transmitter. Be sure the
power switch is on OFF position prior to inserting the plug.
Plug the large end of the adapter into an AC wall socket.
Turn on the power by pressing the POWER SWITCH. Once turned on, the power
indicator will light up.
The transmitter “signal” indicator will illuminate to confirm that the transmitter is
broadcasting.
Press the CHANNEL button on the front panel to select your desired channel.

Setting Up the Transmitter

The 1/4” MIC IN jack on the back of the transmitter is designed to accept either dynamic or electret microphones (microphone not included).
The 1/4” LINE IN jack enables you to connect directly to any audio source (cable not included).

Recommended Microphone Specs:

Microphone Type: . . . . . Dynamic
Frequency Response: . . 80Hz~11KHz
Sensitivity: . . . . . . . . . . -72dB ±3dB (1KHz)
Output Impedance: . . . . 620Ω +30% (1KHz)
Connection: . . . . . . . . . 1/4” jack

Powering the Receiver

Insert 3 “AAA” batteries into the battery compartment on the back of the receiver. Make sure to insert the batteries per the correct polarity. To preserve battery life, always turn the receiver off when not in use. If the sound quality becomes weak or distorted, try relocating the transmitter or adjusting the antenna. If poor sound quality persists, replace the receiver’s batteries. Regular alkaline battery life can last up to 20 hours of receiver use.

Battery Warning

Make sure batteries are installed correctly. Inserting the batteries in the wrong polarity may damage the unit.
Use only the battery type specified.
Do not mix old and new batteries.
Do not mix alkaline, standard (carbon zinc) or rechargeable (nickel cadmium) batteries.
For better performance and longer operating time, we recommend using alkaline batteries.
If the unit will not be used for an extended period of time, remove the batteries.
Discard old or leaking batteries. They can cause damage to the unit and will void the warranty.
Do not try to recharge non-rechargeable batteries; they can overheat and rupture.
Do not dispose of batteries improperly, as the batteries may leak or explode.

Operating the Receiver

Plug the ALSB700 ear buds into the phone jack on top of the receiver.
Turn on the receiver using the POWER SWITCH. The CH1 indicator will light up when receiving a signal. If the receiver is not on the correct channel, the indicator will flash. When the receiver is on the correct channel, the indicator light will be solid. Press the channel button on the receiver to change to the correct channel.
Use GAIN control to adjust the volume to the desired listening level. If there is no sound, make sure the VOLUME on the transmitter is set to a reasonable level.

Tips and Specifications

For optimal performance, make sure:

the transmitter antenna is fully extended.
there are no large structures/obstacles blocking the line of sight between the transmitter and the receiver.
the receivers have new batteries.
to use in an environment of low interference (areas with multiple FM transmissions can possibly increase interference).

Specifications

Frequency Response . . . . . . . . . . . . . . . 100Hz~8KHz
Signal to Noise Ratio . . . . . . . . . . . . . . . 41dB
Total Harmonic Distortion . . . . . . . . . . . . <0.5%
RF Carrier Frequencies . . . . . . . . . . . . . 75.5MHz (CH1)~75.9MHz (CH2)
Frequency Stability . . . . . . . . . . . . . . . . >0.005%
Modulation . . . . . . . . . . . . . . . . . . . . . . . FM +75KHz max.
Operating Range . . . . . . . . . . . . . . . . . . Up to150 feet line of sight
Total Weight . . . . . . . . . . . . . . . . . . . . . . 6.2 lbs.

ALSM700 TRANSMITTER

Mic Input . . . . . . . . . . . . . . . . . . . . . . . . Connector: 1/4” Phone jack Impedance: Unbalanced
Line Input . . . . . . . . . . . . . . . . . . . . . . . . Connector: 1/4” Phone jack Impedance: 100K Unbalanced
Power Output . . . . . . . . . . . . . . . . . . . . . 13dBm
Controls . . . . . . . . . . . . . . . . . . . . . . . . . Power On/Off, Volume Adjust, Channel Select
Indicators . . . . . . . . . . . . . . . . . . . . . . . . Power On LED, Signal LED, CH1 LED, CH2 LED
Antenna . . . . . . . . . . . . . . . . . . . . . . . . . Permanently- mounted, telescope
Power Requirement . . . . . . . . . . . . . . . . 5V DC regulated @200mA, Adapter provided
Dimensions . . . . . . . . . . . . . . . . . . . . . . 9” x 6.07” x 1.97”

ALSR700 RECEIVER

Controls . . . . . . . . . . . . . . . . . . . . . . . . . Power On/Off, Gain Adjust, Channel Select
Audio output . . . . . . . . . . . . . . . . . . . . . 100mW
Connectors . . . . . . . . . . . . . . . . . . . . . . 3.5mm jack for earphone output
Earphones . . . . . . . . . . . . . . . . . . . . . . . Mono ear buds
Antenna . . . . . . . . . . . . . . . . . . . . . . . . . Integral with ear bud cord
Indicators . . . . . . . . . . . . . . . . . . . . . . . . CH1 LED, CH2 LED
Sensitivity . . . . . . . . . . . . . . . . . . . . . . . 3uV for 12dB with squelch defeated Squelches at 10uV for min. 50dB S/N ratio
Mute Threshold . . . . . . . . . . . . . . . . . . . 5~8uV
Power Requirement . . . . . . . . . . . . . . . . 3 “AAA” 1.5V batteries
Battery Life . . . . . . . . . . . . . . . . . . . . . . Up to 20 hours with alkaline batteries
Dimensions . . . . . . . . . . . . . . . . . . . . . . 3.92” x 2.54” x 1.32”