LDG AT-897Plus Operation Manual

AT-897PLUS OPERATIONS MANUAL MANUAL REV B

LDG Electronics

AT-897Plus

Automatic Tuner

for Yaesu FT-897(D)

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1445 Parran Road

St. Leonard MD 20685-2903 USA

Phone: [phone]

Fax: [phone]

[e-mail]

www.ldgelectronics.com

Table Of Contents

Introduction 3
Jumpstart, or “Real hams don’t read manuals!” 3
Specifications 4
An Important Word About Power Levels 5
An Important Word About Tuning on the Six Meter Band 5
Important Safety Warning 5
Getting to know your AT-897Plus 6

Front Panel 7
Rear Panel 8

Installation 9

Compatible Transceivers 9
Mounting the AT-897Plus to the FT-897 Radio 9
Cable Installation 11
Finishing Up Installation 11

Operation 12

Power-up 12
Basic Tuning Operation 12
Toggle Bypass Mode: 13
Initiate a Memory Tune Cycle: 14
Force a Full Tune Cycle: 15
Status LED 16

Application Information 16

Mobile Operation 16
MARS/CAP Coverage 17
Operation with a PC / CAT 17

Theory of Operation 17
The LDG AT-897Plus 19
A Word About Tuning Etiquette 21
Care and Maintenance 21
Technical Support 21
Two-Year Transferrable Warranty 21
Out Of Warranty Service 21
Returning Your Product For Service 22
Product Feedback 222

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INTRODUCTION

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

Congratulations on selecting the AT-897Plus automatic tuner for the Yaesu FT-897
transceiver. The AT-897Plus provides semi-automatic antenna tuning across the entire HF
spectrum plus 6 meters, at power levels up to 125 watts. 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, including the built-in tuners on many
radios.

The AT-897Plus is similar to previous LDG tuners, but is specially engineered to integrate
with your Yaesu FT-897 HF radio. The AT-897Plus connects to the CAT (Computer Automated
Transceiver) port on the back of the radio. The CAT interface allows an external device such as a
PC or the AT-897Plus to control the FT-897 by sending it serial commands. The AT-897Plus
takes advantage of this interface to simplify the tuning process -- one button push is all that is
needed in order to switch the radio to AM mode, reduce output power, transmit a carrier,
measure the transmit frequency, and then restore the radio to its previous mode and power level!

The AT-897Plus is powered by the transceiver’s CAT interface itself, so there is no
additional power cable required to use the AT-897Plus. Latching relays are used, so the AT­897Plus consumes no power when not tuning.

The AT-897Plus improves upon the previous AT-897 automatic antenna tuner, in that the
memory has been expanded to 2,000 frequency memories. The transmit frequency is actually
read directly from the FT-897, so memory tuning is a snap.

JUMPSTART, OR “REAL HAMS DON’T READ MANUALS!”

Ok, but at least read this one section before operating the AT-897Plus:

1. Turn off power to your FT-897 radio.

2. Connect the HF/50 MHz antenna jack on the transceiver to the “Radio” SO-239 jack on the

AT-897Plus, using the supplied 50 ohm coax cable jumper.

3. Connect a 50 ohm coax antenna feedline to the “ANT” SO-239 jack on the AT-897Plus.

4. Connect one end of the supplied radio DIN-8 interface cable to the CAT/Linear port on the

back of your FT-897 radio.

5. Connect the other end of the supplied radio DIN-8 interface cable to the “Radio” jack on the

back of the AT-897Plus.

6. Turn on power to your transceiver. Once it powers up, hold in the FUNC key for one second

to access the extended menus. Rotate the SEL knob until menu #001, “EXT MENU”

appears. Rotate the dial knob until “ON” appears, to activate the extended menus. Rotate the

SEL knob until menu #019, “CAT RATE” appears. Rotate the dial knob until “4800”

appears. Rotate the SEL knob again until menu #020, “CAT/LIN/TUN” appears. Rotate the

dial knob until “CAT” appears. Hold the FUNC key for one second again to return to normal

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operation.

7. Select the desired operating frequency and mode.

8. Push and hold the TUNE button on the front of the AT-897Plus for one second (until the

Tuning LED comes on), then release. The transceiver automatically switches to AM mode,

and keys up with a minimal amount of power, and the AT-897Plus begins a tuning cycle. At

the end of the tuning cycle, the original mode and power level is restored.

9. Wait for the tuning cycle to end; you’re now ready to operate!

SPECIFICATIONS

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0.1 to 125 watts SSB and CW peak power, 100W on digital modes and 6 meters

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Latching relays for ultra low power operation.

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2,000 memories for instantaneous frequency and band changing.

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Powered from the radio -- no extra power supply to hook up.

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Designed specifically for the Yaesu FT-897/FT-897D HF transceivers. Can be mounted

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directly to the side of the FT-897.

.

Pass-thru CAT port allows AT-897Plus to control the FT-897 over the CAT bus while still

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allowing a host PC to also control the radio.
Pass-thru CAT port waits for idle CAT activity before controlling the transceiver.

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1.8 to 54.0 MHz coverage. Frequency for memory storage is read from the radio via CAT.

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Tunes 6 to 800 ohm loads (16 to 150 on 6M), 24 to 3200 ohms with optional 4:1 Balun.

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For Dipoles, Verticals, Vees, Beams or any Coax Fed Antenna.

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

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antennas.
Less than 1 mA power consumption in standby mode -- ideal for battery operation.

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Dimensions: 11.5”L x 1.5”W x 3.25”H.

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Weight: 2.0 pounds

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1

NOTE: On 6 meters, load must be less than 3.0:1 SWR match prior to tuning, or you must reduce power to 50

watts during tuning.

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AN IMPORTANT WORD ABOUT POWER LEVELS

The AT-897Plus is rated at 125 watts maximum power input. Many ham transmitters and
transceivers, and virtually all amplifiers, output well over 125 watts. Power levels that
significantly exceed specifications will definitely damage or destroy your AT-897Plus. If your
tuner fails during overload, it could also damage your transmitter or transceiver. Be sure to
observe the specified power limitations.

AN IMPORTANT WORD ABOUT TUNING ON THE SIX METER BAND

The AT-897Plus is designed to tune loads on 6m that start out at 3.0:1 SWR or lower.
Attempting to tune a greater than 3.0:1 load on six meters at full power can damage your AT-897
tuner. Power levels in excess of 50 watts should be used on 6 meters only if the SWR of the load
was lower than 3.0:1 prior to tuning. If you are unable to check, or are unsure of the SWR

of the load prior to tuning, be sure to reduce power to 50 watts or less when operating on
six meters.

IMPORTANT SAFETY WARNING

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 the nearest power
line should be at least twice the length of the longest antenna, transmission line or
support dimension.

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GETTING TO KNOW YOUR AT-897PLUS

Your AT-897Plus is a quality, precision instrument that will give you many years of
outstanding service; take a few minutes to get to know it.

The AT-897Plus is designed specifically for use with the FT-897, and can be mounted to the
side of the FT-897. The four side feet from your FT-897 fit on the tuner so you can set it down
on its side without danger of scratching the finish. While your AT-897Plus is intended to be
integrated with your FT-897 transceiver, you can also use the tuner simply sitting on a table, not
mounted on the FT-897 transceiver.

Tuning is performed when the Tune button is pushed on the front of the AT-897Plus and
held for one second. The tuner can be placed in bypass mode by pressing the Tune button
momentarily.

The AT-897Plus is powered directly from the CAT port on the radio; no separate power
supply is needed. The AT-897Plus automatically powers up at the start of a tuning cycle, and
goes into an ultra low-power sleep mode when tuning is complete. The latching relays hold the
tuned configuration indefinitely, even when DC power is completely removed. Tuning memories
are stored in FLASH memory.

The AT-897Plus has 2,000 frequency memories. When tuning on or near a previously tuned
frequency, the AT-897Plus uses “Memory Tune” to recall the previous tuning parameters in a
fraction of a second. If no memorized settings are available, the tuner runs a full tuning cycle,
storing the parameters for memory recall on subsequent tuning cycles on that frequency. In this
manner, the AT-897Plus “learns” as it is used, adapting to the bands and frequencies as it goes.

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Front Panel

On the front panel there is one pushbutton and one LED indicator light.

Tune Button: Initiates either a memory tune or a full tune, and also toggles the tuner

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between “active” and “bypass” modes.

Status LED: Lights to give feedback on button presses, lights during tuning; gives tune

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status at the end of a tuning cycle.

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