FM Receivers

97

FM CTCSS Sensitivity and Bandwidth Measurement
Description

This procedure is used to measure an FM Receiver’s Continuous Tone Coded

Squelch System (CTCSS) sensitivity and bandwidth. For sensitivity, the

minimum signal input at the Receiver’s antenna (modulated with tone) that

opens the squelch is measured and displayed. Squelch hysteresis is also

measured and calcul ated. Tone frequency is then increased a nd decreased until

the squelch boundaries are determined and the Bandwidth is calculated.

Reference is A NSI/EIA RS- 220A.

DUPLEXTXRX PREV TESTS
CONFIGHELPMSSG HOLD PRINT
SCREEN CONTROL
LOCAL
ADRS
RECALL
SAVE
MEAS
RESET PRESET
INSTRUMENT STATE
DATA FUNCTIONS
INCR
: 10
REF SET
INCR
SET
METER
INCR X10
AVG
LO LIMIT HI LIMIT
CURSOR CONTROL
PUSH TO SELECT
CANCEL
SHIFT
k1
k1’
k2
k2’
k3
k3’
k4
ASSIGN
k5
RELEASE
USER DATA
789
456
123
0+
_
ENTER
GHz
dBm
dB
MHz
V
%
kHz
mV
s
Hz
µV
ms
%
dBµV
Ω
ppm
W
NO
ON/OFF
YES
MEMORY
CARD
AUDIO IN LOHI
!MAX
42 v Pk
!MAX
12 v Pk
AUDIO OUTSQUELCHVOLUMEMIC/ACC
MAX POWER 200 mW
!
ANT INDUPLEX OUTRF IN/OUT
!MAX POWER 60 W
CONTINUOUS
POWER
OFF ON
1
2
Data Entry
RX TEST

50Ω COXIAL

CABLE
TEST LOAD
RECEIVER UNDER TEST
ANTENNA (RF INPUT)
SPEAKER

(AUDIO

INPUT)
3
+
GND
Knob Keys