Icom IC R8500 Service Manual Addendum page 232

5-3 RECEIVER ADJUSTMENT
ADJUSTMENT
PIN ATT 1 • Displayed freq.
• Mode
• Receiving
HF 1 • Displayed freq.
SENSITIVITY • Mode
• [10dB]
• [AGC]
• Connect an SSG to the antenna connector for
0.1–30 MHz (50 Ω ANT) and set as;
Frequency
Level
Modulation
• Receiving
2 • Set the SSG output level : OFF
• Receiving
1ST MIXER 1 • Displayed freq.
BIAS • Disconnect J4.
VOLTAGE • Receiving
HPF SHIFT 1 • Displayed freq.
VOLTAGE • Mode
• Receiving
2 • Displayed freq.
• Receiving
NOTE: Before adjusting WFM SENSITIVITY, 5-4 RF-C BPF TUNED VOLTAGE ADJUSTMENT must be performed.
WFM 1 • Displayed freq.
SENSITIVITY • Mode
• Connect an SSG to the antenna connector for
30–2000 MHz and set as;
Frequency
Level
Modulation
Deviation
• Receiving
2 • Set the SSG output level : 3.2 µV* (–97 dBm)
• Receiving
3
FM 1 • Displayed freq.
SENSITIVITY • Mode
• Connect an SSG to the antenna connector for
30–2000 MHz and set as;
Frequency
Level
Modulation
Deviation
• Receiving
2 • Set the SSG output level : 0 dBµ* (–107 dBm)
• Receiving
1ST IF 1 • Displayed freq.
NOTCH • Mode
• Connect an SSG to the antenna connector for
30–2000 MHz and set as;
Frequency
Level
Modulation
Deviation
• Receiving
*This output level of the SSG is indicated as SSG's open circuit.
ADJUSTMENT CONDITIONS
: 14.10000 MHz
: USB
: 14.09850 MHz
: USB
: ON
: Fast
: 14.10000 MHz
: 0.56 µV (–112 dBm)
: OFF
: 173.00000 MHz
: 1300.00000 MHz
: FM
: 1100.00000 MHz
: 173.02000 MHz
: WFM
: 173.02000 MHz
: 1 mV (– 47 dBm)
: 1 kHz
: ±75 kHz
: 173.02000 MHz
: FM
: 173.02000 MHz
: 3.2 µV* (–97 dBm)
: 1 kHz
: ±5 kHz
: 788.60000 MHz
: FM
: 810.00000 MHz
: 32 mV* (– 17 dBm)
: 1 kHz
: ±75 kHz
MEASUREMENT
UNIT LOCATION
RF-C C o n n e c t a d i g i t a l
multimeter to CP1.
Rear C o n n e c t a n A C
panel voltmeter to the [EXT
SP] with an 8 Ω load.
RF-D C o n n e c t a d i g i t a l
m u l t i m e t e r t o b o t h
terminal of R91.
CONV-B C o n n e c t a d i g i t a l
multimeter to CP2.
MAIN-A C o n n e c t a d i g i t a l
multimeter to CP1.
C o n n e c t a d i g i t a l
multimeter to CP4.
C o n n e c t a d i g i t a l
multimeter to CP1.
Front S-meter
panel
MAIN-A C o n n e c t a d i g i t a l
multimeter to CP5.
Front S-meter
panel
5 - 3
ADJUSTMENT
POINT
VALUE
UNIT ADJUST
1.7 V RF-C R63
Maximum Adjust in
output sequence
level L65, L66,
L63, L62
repeatedly
Minimum R77
output
level
0.2 V RF-D R109
14.5 V CONV-B R55
3.0 V ±1.0 V Verify
2.5 V MAIN-A C37
Minimum Adjust in
level sequence
L7, L8, L9,
L10
repeatedly
2.45 V C37
Maximum MAIN-A Adjust in
level sequence
L14, L17,
L22, L25,
L26
repeatedly
2.45 V MAIN-A R60
Maximum MIX-A L15
level