Viking 242-2009-632 - Manual (Page 145)

ALIGNMENT AND TEST PROCEDURES
7-17
March 1999
Part No. 001-2009-600
Data Level Adjustment
1. Remove VNC cards if present. (Set modulation
analyzer LPF switch to 3 kHz.) Final adjustment
must be performed on the customer channel.
2. Use the "Turn on carrier" button to key the transmit-
ter.
3. Adjust U151 with the Level Control buttons to
achieve
±
750 Hz
±
50 Hz transmit deviation.
4. Use the "Turn on carrier" button to unkey the trans-
mitter.
Audio/Data Deviation Check
1. Remove VNC cards if present.
2. Apply a 1 kHz tone at +7 dBm (1.73V RMS) to
P100, pin 32 of the MAC. (Set modulation analyzer
LPF to 3 kHz.)
3. Use the "Turn on carrier" button to key the transmit-
ter.
4. Check for measured deviation out of the modulation
analyzer to be
±
2.4 kHz +100/-200 Hz.
5. Use the "Turn on carrier" button to unkey the trans-
mitter.
6. Disconnect all cables.
CWID Level Check
1. Set modulation analyzer LPF switch to 3 kHz. Use
the "Turn on carrier" button to key the transmitter.
2. Deviation should measure between 750 Hz and
1250 Hz.
3. Use the "Turn on carrier" button to unkey the trans-
mitter.
Local Speaker/Microphone Check
1. Plug a Speaker/Microphone into J101/J102 of the
MAC. Set modulation analyzer LPF switch to
3 kHz.
2. Press the microphone PTT and say "four" loudly
into the microphone.
3. Deviation should measure
±
1.4-1.6 kHz.
4. Release the microphone PTT.
Transmitter Hum and Noise Ratio (Optional)
NOTE: An HP8901A modulation analyzer is required
for this test.
1. On the modulation analyzer press:
300 Hz HPF
3000 Hz LPF
FM
Pre-Display
750
µ
S
Avg RMS Cal
0.22
dB
2. Use the "Turn on carrier" button to key the transmit-
ter and measure the Hum and Noise Ratio. The
reading shall be < -45 dB.
3. Use the "Turn on carrier" button to unkey the trans-
mitter.
Transmit Audio Distortion
1. Remove VNC cards if present. On the modulation
analyzer select:
FM
50 Hz
15 kHz
2. Apply 200 mV RMS at 1 kHz to P100, pin 32 of the
MAC.
3. Use the "Turn on carrier" button to key the transmit-
ter.
4. Adjust audio level to produce
±
1 kHz deviation.
5. On the modulation analyzer select:
300 Hz
3 kHz
750
µ
s de-emphasis
6. Distortion should be < 2%.