D Antenna Tuner - Icom IC-7851 Servise Manual

D Receiver
• Receive system:
• Intermediate frequencies:
• Sensitivity:
SSB, CW, RTTY, PSK (BW=2.4 kHz, 10 dB S/N)
AM (BW=6 kHz, 10 dB S/N)
FM (BW=15 kHz, 12 dB SINAD)
• Selectivity (with optimum roofi ng fi lter):
SSB, RTTY (BW=2.4 kHz)
CW/RTTY/PSK (BW=500 Hz)
AM (BW=6 kHz)
FM (BW=15 kHz)
• Spurious and image rejection ratio:
• Squelch sensitivity (pre-amp OFF):
SSB, CW, RTTY, PSK31/63
FM
• RIT variable range:
• Audio output power:
• PHONES connector:
• EXT-SP connectors:

D Antenna tuner

• Matching impedance range:
• Minimum operating input:
• Tuning accuracy:
• Insertion loss (after tuning) :
* The LCD display may have cosmetic imperfections that appear as small or dark spots. This is not a malfunction
or defect, but a normal characteristic of LCD displays.
Spurious signals may be received near the following frequencies. These are made in the internal circuit and does
not indicate a transceiver malfunction.
• 0.150 MHz, 1.049 MHz, 19.660 MHz and 24.576 MHz
Spurious waveforms may be displayed on the spectrum scope screen regardless of the transceiver's condition
(Tx or Rx). They are made in the scope circuit. This does not indicate a transceiver malfunction.
All stated specifi cations are typical and subject to change without notice or obligation.
Double conversion superheterodyne system
1st 64.455 MHz (MAIN band)
64.555 MHz (SUB band)
2nd 36 kHz
0.100–1.799 MHz 0.5 µV
1.800–29.990 MHz 0.16 µV
50.000–54.000 MHz 0.13 µV
0.100–1.799 MHz 6.3 µV
1.800–29.990 MHz 2 µV
50.000–54.000 MHz 1 µV
28.000–29.990 MHz 0.5 µV
50.000–54.000 MHz 0.32 µV
More than 2.4 kHz/–3 dB
Less than 3.6 kHz/–60 dB
More than 500 Hz/–3 dB
Less than 700 Hz/–60 dB
More than 6.0 kHz/–3 dB
Less than 15.0 kHz/–60 dB
More than 12.0 kHz/–6 dB
Less than 20.0 kHz/–60 dB
More than 70 dB
Less than 5.6 µV
Less than 1 µV
±9.999 kHz
More than 2.6 W
3-conductor 6.35 (d) mm (
2-conductor 3.5 (d) mm (
16.7 to 150 Ω unbalanced
20 to 125 Ω unbalanced
8 W
15 W
VSWR 1.5:1 or less
Less than 1.0 dB
(pre-amp 1 ON)
(pre-amp 1 ON)
(pre-amp 2 ON)
(pre-amp 1 ON)
(pre-amp 1 ON)
(pre-amp 2 ON)
(pre-amp 1 ON)
(pre-amp 2 ON)
at 10% distortion with an 8 Ω load
1
(50 MHz band; VSWR better than 2.5:1)
(HF bands)
(50 MHz band)
1-2
)
1 ⁄
4
)/8 Ω2
⁄
(for main and sub)
8
(HF bands; VSWR better than 3:1)