LDG AT-7000 User Manual

AT-7000

Automatic Antenna Tuner

For Icom Transceivers

Manual Version 1.1

LDG Electronics

1445 Parran Road

St. Leonard MD 20685 USA

Phone: [phone]

Fax: [phone]

[e-mail]
www.ldgelectronics.com

Copyright © LDG Electronics 2006. All rights reserved.

LDG AT-7000

Automatic Antenna Tuner

For ICOM IC-7000

Introduction 3
Jumpstart, or “Real Hams Don’t Read Manuals!” 3
Specifications 4

An Important Word About Power Levels 4

Getting To Know Your AT-7000 5
Operation 8
Application Notes 9

Fixed Station Operation 9
Expert Button 9
Mobile Operation 11
MARS/CAP Coverage 11

Theory Of Operation 12

Some Basic Ideas About Impedance 12
Transmitters, Transmission Lines, Antennas and Impedance 12

The LDG AT-7000 13
A Word About Tuning Etiquette 15
Care and Maintenance 15
Technical Support 15
Warranty and Service 15
Firmware Upgrades 15

2

Introduction

Congratulations on selecting the LDG AT-7000 tuner. The AT-7000 provides automatic antenna
tuning for your Icom IC-7000 (and some other Icom radios that are AH-3 or AH-4 compatible)
across the entire HF range plus 6 meters. It will tune dipoles, verticals, Yagis or virtually any
coax-fed antenna. It will match an amazing range of antennas and impedances, far greater than
some other tuners you may have considered. The AT-7000 uses little power while tuning, and
with its latching relays, uses essentially no power in standby.

The AT-7000 represents a quantum leap in features and performance. Enhanced tuning
algorithms provide much faster, precise and consistent tuning.

LDG pioneered the automatic, wide-range switched-L tuner in 1995. From its laboratories near
the nation’s capitol, LDG continues to define the state of the art in this field with innovative
automatic tuners and related products for every amateur need.

Jumpstart, or “Real Hams Don’t Read Manuals!”

Ok, but at least read this one section before you transmit:

1. Connect the HF antenna jack on your transceiver to the "TX" jack on your AT-7000

tuner using the provided jumper cable.

2. Connect your 50 Ohm antenna coax lead to the "Ant" jack on the back of your AT-

7000.

3. Connect the tuner’s RADIO port to your IC-7000 transceiver’s Tuner port using the

provided cable.

4. Power up your transceiver and select the desired operating frequency and mode.

5. Press and hold the TUNER/CALL button on the radio for one second, then release.

6. Wait for the tuning cycle to end and for the TUNE icon to appear on the radio’s

display.

7. You’re now ready to operate.

3

Specifications

g

•

0.1 to 125 watts SSB and CW peak power, 100 watts digital

• 2,000 memories for instantaneous frequency or band changing

• Tuning time: 0.5 to 6 seconds full tune, < 0.1 second memory tune

• Built in frequency counter for memory operation

• Frequency coverage: 1.8 to 54.0 MHz.

• Tunes 4 to 800 ohm loads (16 to 150 ohms on 6M), 16 to 3200 ohms with

optional 4:1 Balun (LDG RBA-4:1)

• For Dipoles, Verticals, Vs, Beams or and Coax Fed Antenna

• Optional external Balun allows tuning of random length, long wire or ladder line

fed antennas

• Dedicated interface to the IC-7000 transceiver (and some other Icom radios)

• Power requirements: 11 to 16 volts DC at 250 mA max during tuning, < 8mA

idle, provided by the Icom transceiver

• Enclosure: 6.5 x 6.5 x 1.5 inches

• Weight: 1.5 pounds

An Important Word About Power Levels

The AT-7000 is rated at 125 watts maximum power input at most. Many ham transmitters and
transceivers, and virtually all amplifiers, output well over 125 watts. Power levels significantly
exceeding specifications will definitely damage or destroy your AT-7000. If your tuner fails
during overload, it could damage your transmitter or transceiver. Be sure to observe the specified
power limitations.

Never install antennas or transmission lines over or near
power lines. You can be seriously injured or killed if any part
of the antenna, support or transmission line touches a power
line. Always follow this antenna safety rule: the distance to

IMPORTANT SAFETY WARNING

the nearest power line should be at least twice the length of
the lon

est antenna, transmission line or support dimension.

4

Getting To Know Your AT-7000

Your AT-7000 is a quality, precision instrument that will give you many years of outstanding
service; take a few minutes to get to know it.

Your AT-7000 is designed specifically to work with the ICOM IC-7000 transceiver. It can also be
used with other ICOM transceivers that are compatible with AH-3 and AH-4 antennas.

There are no controls or readouts on the AT-7000. All functions are controlled by the
TUNER/CALL button on your IC-7000.

Your AT-7000 is powered directly by the radio; it needs no separate power supply. Your AT­7000 automatically powers up whenever you start a tuning cycle, and after tuning, automatically
enters a “deep sleep” state in which it draws less than 8 mA. The tuner will automatically "wake
up" the next time you start a tuning cycle. The latching relays hold the tuned configuration
indefinitely, even while DC power is completely removed. Tuning memories are stored
indefinitely in EEPROM memory.

The AT-7000 has 2,000 frequency memories. When you transmit on or near a previously tuned
frequency, your AT-7000 automatically uses “Memory Tune” to reset the tuning parameters in
only a fraction of a second. The process of storing tuning settings in memory is completely
automatic; your AT-7000 literally “learns” as you use it, adapting itself to all of the bands and
frequencies you use. If no memorized settings are available, the tuner runs a full tuning cycle,
storing the parameters for memory recall on later tuning cycles on that frequency.

5