Pll And Transmitter Adjustments - Icom IC-UR8050 Service Manual

3-2 PLL AND TRANSMITTER ADJUSTMENTS

ADJUSTMENT ADJUSTMENT CONDITIONS
PLL LOCK 1 • Operating freq.
VOLTAGE • Apply DC voltage : 13.8 V
[VOLUME]
[SQUELCH]
• Connect an RF power meter or termi-
nator to the [TX ANT] connector.
• Transmitting
2 • [LOCAL INHIBIT] switch : ON
• Receiving freq.
[VOLUME]
• Receiving
REFERENCE 1 • Operating freq.
FREQUENCY • Transmitting
OUTPUT 1 • [LOCAL INHIBIT] switch : ON
POWER • Operating freq.
• Apply DC voltage
[VOLUME]
[SQUELCH]
• Transmitting
1
DEVIATION • [LOCAL INHIBIT] switch : ON
(MAXIMUM) • Set an FM deviation meter as :
HPF
LPF
De-emphasis
Detector
• Disconnect P1 from J5 on the TX
unit, connect an audio generator to J5
and set as
• Transmitting
2
• Set an AG as
• Transmitting
After adjustment, connect P1 to J5 on the TX unit.
3
4
(MICROPHONE) • Connect an AG to [MIC] connector
and set as
• Transmitting
5
(REPEATER) • [LOCAL INHIBIT] switch : OFF
• Connect an SSG to the [RX ANT]
connector and set as:
Level
Deviation
Modulation
• Receiving
6
•Set an SSG as
Deviation
• Receiving
*This output level of the standard signal generator (SSG) is indicated as the SSG's open circuit.
UNIT
: 415.000 MHz TX
: Max. CCW
: Max. CW
RX
: 415.050 MHz
: "11 o'clock" position
:415.000 MHz Rear
panel
Rear
:415.000 MHz panel
: 13.8 V
: Max. CCW
: Max. CW
Rear
panel
: OFF
: 20 kHz
: OFF
: (P–P)/2
: 1 kHz/ 1 V
: 50 Hz/ 1 V
Rear
: 1 kHz/ 4 mV panel
: 1 mV*
(60 dBµ)
: ±3 kHz
: 1 kHz
: ±5.0 kHz [#03]
: ±2.5 kHz [#04]
3 - 2
MEASUREMENT
LOCATION
Connect a digital multi-
meter or an oscillo-
scope to check point
[LV].
Connect a digital multi-
meter or an oscillo-
scope to check point
[LV].
Loosely couple a fre- 414.9999–
quency counter to the 415.0001 MHz
[TX ANT] connector.
Connect an RF power
meter or a terminator
to the [TX ANT] con-
nector.
Connect an FM devia-
tion meter to the
[TX ANT] connector
through an attenuator.
Minimum devia-
tion, and a con-
nected oscillo-
scope to the FM
deviation meter
as shown below.
Connect an FM devia-
tion meter to the
[TX ANT] connector
through an attenuator.
#03:
±3.0–5.0 kHz
#04:
±1.5–2.5 kHz
ADJUSTMENT
VALUE
UNIT ADJUST
2.7 V TX
2.4 V RX
TX
(F–SET)
47 W PA
#03: ±4.7 kHz TX
#04: ±2.3 kHz (MOD)
(R–MOD)
as flat as possible
#03: ±3.0 kHz LOGIC
#04: ±1.5 kHz (MIC)
(MOD)
Verify
L3
L16
R38
R16
(Hi)
R50
R43
R61
R47