Icom IC-7400 Instruction Manual Download

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QUICK REFERENCE GUIDE

2001 NEW

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Installation

1. Install a ground system for DC noise suppression

and RFI suppression

2. Install your DC power supply
3. Install lightning protection. This will help protect

more than your gear.

4. Install and connect an antenna system for the ap-

propriate bands of operation

5. Connect other peripheral equipment. This includes

microphones, headsets, TNC, amplifiers and any
other equipment necessary to make your shack
complete.

Although your radio will operate by connecting the DC
power supply and antenna, it is necessary to have a
good ground system in your shack. A ground connec-
tion is the electrical contact between the common point
of an electrical or electronic system and the earth.

A good earth ground is necessary to prevent electrical
shock, eliminate problems from RFI and DC noise.
With more electronic devices being used today, it is
also important to reduce RFI and EMI. Although you
may not see interference in your shack, without a
grounding system, your neighbors may experience in-
terference. Even though many of these devices,
where they must accept interference from their sur-
rounding environment, it is best to eliminate as much
of the possible interference from your shack.

If you do not have a grounding system for your shack,
depending on the location of your shack, basement or
ground floor, a good ground system can be as simple
as a couple of ground rods driven 2 to 2.5 meter into
the soil. When installing your IC-7400 to your ground-
ing system, the shortest most direct connection is rec-
ommended.

NOTE:

There are many publications covering

proper grounding techniques. Check with your local
dealer for more information and recommendations.

WARNING!: NEVER

ground station equip-

ment or antennas to house gas lines.

NEVER

at-

tach ground lines to plastic (pvc) pipe.

Some Symptoms if inadequate grounding

a. Poor DC Ground

50/60 Hz hum on the audio either Rx or Tx without
the antenna connected.

If you feel a tingling sensation when you touch a
metal surface. Surfaces such as the cover of your
radio or power supply.

b. Poor RF Ground

While transmitting and you feel a tingling sensation
when you touch a metal surface. Surfaces such as
the cover of your radio or power supply.

While transmitting, you experience interference to
other electronic devices, such as the telephone,
television or stereo audio systems.

The DC power supply is a device used to convert
110/220 V AC, also know as Household current, to a
steady source of 13.8 V DC.

The perfect match to your IC-7400 is the PS-125. This
compact switching power supply is the matching
power supply for your IC-7400 with a current rating of
25 A continuous duty. This plug and play unit plugs
into the DC jack located on the rear of the radio.

• If you are not using the PS-125:

Connect the supplied DC power cable to the appro-
priate color coded terminals, then insert the DC con-
nector into the DC jack located on the rear of the
radio.

(The diagram below describes the connection with

OPC-639. OPC-025D has no filter box and GND cable.)

NOTE:

Although the power supply current require-

ment is quite low during receiving, this not the case
when you transmit. With many electrical devices in
the shack, it is very important to verify the electrical
circuit is not overloaded.

30 A fuses

AC cable

Transceiver

outlet

A DC power

supply*

*13.8 V; at least 23 A

continuous

Black

Red

to DC power
socket

Supplied
DC power cable