AVSL VH45B User Manual

Operation

Power supply - Receiver

9-15Vdc (adapter supplied) 200mA

Power supply - Transmitter

9Vdc batter (PP3 type, supplied)

Carrier frequency

174.5MHz

Max deviation

±25kHz

Dynamic range

>90dB

THD

<0.5%

Frequency response

40Hz-15kHz ±3dB

Audio output

400mV

Signal to noise ratio

>90dB

Channel rejection

>80dB

Receiver sensitivity

10dBuV

Max continuous battery life

10 hours

Dimensions - Receiver / Transmitter

150 x 110 x 35mm / 250 x 50mmØ

Weight - Receiver / Transmitter

190g / 280g

 With levels turned down, connect a 6.3mm jack lead from the receiver to the P.A.

system or mixer and extend the antenna vertical to the receiver unit.

 On the handheld transmitter, with the POWER switch off, unscrew the battery cover

and connect a good 9V (PP3) battery to the contacts, taking note that the “+” and “-“
connections are correct

 With the VOLUME control turned fully down (anticlockwise), connect the DC adapter

to the receiver unit and then into the mains outlet, making sure that the adapter and
lead are in good condition.

 Switch on the POWER on the handheld transmitter and check that the RF LED is

illuminated on the receiver. Switch off the MUTE and speak loudly into the
microphone, checking that the AUDIO PEAK LED on the receiver flashes with the
loudest sounds

 Turn up the level on the P.A. system or mixer and then turn up the VOLUME control

(clockwise) on the receiver. The microphone should now be heard through the P.A.
system or mixer

 After use, turn down the level on the P.A. system or mixer and then turn down the

VOLUME on the receiver, MUTE the transmitter and switch off POWER

 Disconnect the receiver from the P.A. system and then unplug from the mains
 If not used for a long period of time, remove the battery from the transmitter

VH45B

Wireless Microphone System

171.801

Specifications

1622

© QTX Sound 2010

USER MANUAL

Thank you for your purchase of the VH45B wireless microphone system. Please read

the following instructions carefully before using this product to ensure best results and

to avoid damage through misuse.

Note – no user serviceable parts inside, refer all servicing to a qualified technician.

Safety

 Connect the D.C. adapter to the wireless receiver and ensure the correct mains

voltage and that the D.C. adapter and lead is intact before plugging into the
mains outlet

 Ensure that the handheld transmitter has a 9V battery (PP3) installed which is

in good condition with adequate charge (alkaline type is recommended)

 Avoid contact with moisture for any of the system components and keep all

parts clear of dust and foreign objects

 Keep all components away from heat sources (amplifiers, heaters, radiators

etc.) and out of direct sunlight

 Remove battery from the handheld unit and power adapter from receiver

when not being used for long periods of time.

 Position the receiver on a stable surface and take care when placing the

transmitter down so that it doesn’t roll and fall off the surface.

 Clean transmitter and receiver periodically with a dry or slightly damp cloth.

Do not use solvents or abrasives on the plastic and metal parts.

 Avoid impact or pressure on casing of all components

Features

 Stable quartz tuned VHF carrier frequency
 Multi-level high and mid frequency narrowband filtering to eliminate

interference.

 Individual Mute switch on handheld transmitter to allow muting prior to

switching on or off, avoiding clicks and pops

 LED indicators for Power, RF, Audio Peak, Low battery
 Audio companding circuitry for accurate dynamics without audible distortion
 Auto-muting circuitry to eliminate noise when transmitter is not detected
 Neat and compact design

Receiver

1. POWER LED – illuminated when power to receiver is on

2. RF LED – illuminated when receiver detects RF carrier signal

3. AUDIO PEAK LED – illuminates to indicate audio reaching peak level

4. VOLUME – rotate clockwise to increase output level

5. ANTENNA – fold-away VHF telescopic aerial

6. OUTPUT – 6.3mm jack unbalanced audio output

7. CASE – sturdy plastic receiver housing

8. DC INPUT – 2.1mm power connector for 9-15Vdc input

Transmitter

1. GRILLE – windshield with integral pop filter

2. LOW BATT LED – illuminates when battery charge is low

3. POWER LED – illuminates to show battery power is on

4. POWER & MUTE – switches to activate battery and mute output

5. GAIN – screw adjustment inside battery compartment to adjust mic gain

6. COVER – screw-on cover for battery compartment