Receiver unit and power supply
Features:
¥High sensitivity effective over 100m range.
¥Low noise muting circuits.
¥Crystal controlled VHF/FM.
¥High signal/noise ratio (8 pole ceramic filter).
¥Good immunity from taxis, CBÕs, etc.
1. Attach rigid aerial (supplied) to socket on rear panel.
2. Insert 2.1mm d.c. coax socket and lead (supplied) to
15V d.c. input socket on rear panel; plug in power
supply unit to 240V 50Hz mains.
3. Check that red LED on front panel is illuminated.
4. With microphone switched off (i.e. microphone LED
not illuminated) check that the green (carrier) LED on
the front panel is also off (see noise muting
instructions if illuminated).
5. Switch microphone on (microphone LED illuminated)
and check that green LED on front panel is also
illuminated.
6. Connect audio output to power amplifier via (a) 600 ½
unbalanced 0.25 inch jack socket, or (b) 150 ½
balanced XLR socket.
Note: audio level may be adjusted on unbalanced
output only.
Noise muting adjustment
In particularly noisy environments (i.e. r.f. noise within
the operating frequency range) the internal mute level
may need to be adjusted. The need to make
adjustments will be evident if the green (carrier) LED on
the front panel illuminates before the microphone is
switched on, with possible noise on the loudspeaker
outputs.
With a small screw driver or trim tool (RS stock no. 543-434)
and with the microphone still switched off, turn the mute
adjustment trimmer clockwise until the carrier LED turns
off. (This is accessed through the small hole in the base
of the receiver unit). Do not over adjust as this will
decrease the working range of the microphone system.
Note: Make this adjustment on site where r.f. noise is
being experienced.
Receiver unit specification
Power supply: 15V d.c., 200mA unregulated
(coax socket centre pin positive)
RF carrier frequency: 173.8MHz (RS stock no. 245-146)
175.0MHz (RS stock no. 245-152)
Superhetrodyne
IF frequency: 10.700MHz.
RF sensitivity: 1µV for 20dB of noise quieting
Image rejection: Better than 90dB.
Frequency stability: Better than 0.005%. Quartz
controlled
Antenna: Detachable 1/4 wave rod
Audio signal/noise ratio: Better than 94dBA.
Audio distortion: Typ 0.5%
Audio frequency
response: 20Hz to 15kHz within 3dB.
Audio outputs: Balanced line - 150 ½, -37dBM.
Unbalanced line - 600 ½, 0dBM
adjustable
Construction: 2 piece ABS moulding
Dimensions: 6 x 6.75 x 2 inches
(150 x 175 x 50mm)
A. Balanced line 150½ audio output
B. Audio output (600½)
C. Aerial
D. 15V d.c. supply socket
E. Audio level adjust
Figure 2 AB
C D E
RS Components Issued March 1993 8516
Rear view
