Test Procedure; Rf Cable Test; To Test The Rf Cable For Proper Loss - Motorola T720 Service Manual

Test Procedures

RF Cable Test

Tx Fr equency
Off
Tx P ow er
d B m
-0.62
Tu ne M de
Rf Gen Freq
Auto / Ma nu al
o 834 .99 0000
MHz
Tun e Freq
Ampli u de
83 4.990000
t
0.0
MHz
dBm
Atte n Ho d
In put Port
l
RF In/ A nt
On /Off
IF Filter
Ou tpu t Port
15 K Hz
RF Ou t / D up l
Ex t T Xkey
On /
Off
In order to properly measure and adjust the
parameters of a telephone, it is important that
you use RF cabling that has minimal loss.
Therefore, it is important that you test the RF
cable for proper loss. This can easily be done
by using the DUPLEX TEST screen of your
HP8924. To test the cable, set up the DU-
PLEX screen as shown above.
Action:
Take the cable under test and connect it from
the RF in/out port to the Duplex Out port. At
this point you will be getting some type of
power reading for cable loss.
Good range: -.2 dBm through -.8 dBm
Bad cable: More than -.8 dBm
If the reading you are getting shows gain (posi-
tive number,)you may need to zero the power
meter. This may happen on an HP8924 whose
Motorola Confidential Proprietary
D U P LE X TE ST
AC Level
d B
SINAD
AF Anl In
AF Gen1 Fre q
1.00 00 Aud io In
Filter 1
A FGe n1 To
5 0 H z HP F
FM Off
Filter 2
KHz
15kH z LP F
FM C oupli ng
AC / DC
DE Emphasis
750 us / Off
Aud io Out
AC / DC
De te cto r
RM S
To test the RF cable
for proper loss:
Off
Tune Freq should be set to
ï
TX frequency: 834.990000 MHz.
Off
RF Gen Freq should be set
ï
to same frequency (834.990000
MHz).
To Screen
Tx Power should be set to
ï
C D M A
CALL CNTL
read in dBm, not Watts.
SMS
AUTHEN
A nalog
RX TEST
C o nfig
PRNT C NFG
memory has just been cleared.
To zero the meter, press the TX button on
the 8924 panel. Bring the cursor down to the
field under TX Pwr Zero where it reads Zero
Tap the cursor on the Zero field and it will
highlight for a moment as it zeroes the meter.
Set up the screen as shown above, and test
your cable.
44
CDMA T720
.