RT Transmitter User Guide – Marshall Radio Telemetry

Owner's manual. Transmitters

How to use the RT transmitter

This is the 2008 RT. It runs about 3 days at full pulse, warns you, then keeps going for about 7 more days. Weight with the battery is 9 grams.

Tested to 300 kilometers, line of sightAbout 10 days in total13.25 inch antennaLow-battery warning

Getting started

What is different on this model

Low-battery warning. A timer plus a live voltage check. It also warns you if you install an old battery.
Battery contacts. Both contacts touch the battery. The lid no longer has to stay perfectly clean.
Build. Stable frequency, hard-coat anodizing, a high-impact crystal, Power Line Static Protection, and an Easy Crank case.

Install the battery

The RT uses a 1/3N lithium photo battery. Marshall recommends the Duracell DL1/3N. Put the positive side toward the lid. The positive side is marked with a plus sign. Screw the lid on with your fingers. The round battery spring pushes back on the lid so it does not unscrew. The transmitter starts as soon as the battery is in.

Positive side toward the lid. Finger tight. It starts at once.

How long the battery lasts

The 2008 RT transmits for about 3 days, then gives a double beep every 10 pulses. After that warning it runs about 7 more days.

Turn it on and off with the magnet

Hold the magnet near the base of the antenna. You will hear 5 fast beeps on the receiver when it turns off, and 3 fast beeps when it turns on. The short wait keeps a brush of the magnet from turning it off by accident.

Marshall magnetic wand on its keyring — The magnetic wand ships with the transmitter. Spare wands are in the store.

If you lose the magnet, unscrew the lid to cut power. Listen for the signal before you fly, and again after you switch it off. The drain is so low that a new battery is still fine after two years inside a transmitter that is switched off.

Wash and inspect

The RT is waterproof. You can wash it with hot water. Dry the inside of the case and the lid before you install a battery. Replace the antenna as soon as you see a crack or bare wire.

Replace the antenna

Use only a genuine Marshall antenna with Power Line Static Protection. Length is 13.25 inches for 216 or 233 megahertz. On this model, slice the old epoxy off the antenna base with an X-acto knife before you unscrew it.

Slice off the old epoxy at the antenna base with an X-acto knife.
Unscrew the protector, then unscrew the old antenna with your fingers.
Screw the new antenna on hand tight. A small bead of quick-drying epoxy at the base is fine.
Put the protector back on.

Protector off, old antenna off, new antenna hand tight, protector back on.

Do not use liquid super glue or a thread locker. Super glue runs up the threads and bonds to the antenna stud. Unscrew the old antenna with your fingers only. Pliers can damage the transmitter.

What range to expect

Tested past 300 kilometers, line of sight. In the western deserts of the United States, hunts have run from 9 to 100 kilometers, depending on height, ground, obstacles, and radio noise. The RT has about twice the range of the Marshall RT Plus used in the United States and Europe.

How it mounts on the bird

Match the photo to the hardware you ordered. The bird photos show the leg and tail methods. They use a GPS transmitter so you can see where the hardware sits.

Marshall tail spring — The tail spring used on the RT. The blue washer holds it on the antenna.

Close view of a leg mount on a bird. — Leg mount on a bird. The transmitter in this photo is a GPS unit. The bewit sits beside the foot and the antenna points back.

A peregrine with a tail-mounted transmitter under the tail. — Tail mount on a bird. The transmitter in this photo is a GPS unit. It hangs under the tail and the antenna points down.

Point the receiver

The signal from the RT is strongest when the receiver antenna lines up with the transmitter antenna.
A bird on a perch holds its tail nearly straight up. Hold the receiver elements straight up.
A bird on the ground can leave the antenna nearly flat. Turn the elements flat and listen again.
If you can hear the signal both ways, use the flat position to pinpoint the bird.

Receiver with a three-element antenna, elements held flat — The receiver with its three-element antenna. The elements in this photo are flat, the position for a bird on the ground. Turn them straight up for a bird on a perch.

Warranty

Marshall Radio Telemetry warrants that the RT transmitter will be free from defects of workmanship and materials for three (3) years from the date of purchase by the end user. Return a defective transmitter directly to Marshall Radio Telemetry and we will repair or replace it and return it free of charge. Damage from misuse or normal wear and tear is not covered, and the warranty is void if a non-Marshall antenna has been used. Marshall Radio is not responsible for damages or loss beyond the value of the transmitter itself, including but not limited to the loss of a bird or lost time.

This device does not interfere with television reception or Federal Government radar.

Troubleshooting

Work down this list before you change anything else.

You hear a double beep every 10 pulses. About 3 days have passed, or the battery is old. The transmitter will run about 7 more days. Change the battery when you can.
It will not turn off or on. Hold the magnet near the antenna base until you hear 5 fast beeps for off, or 3 fast beeps for on. If the magnet is lost, unscrew the lid.
The antenna will not unscrew. Slice the old epoxy off the base with an X-acto knife, then unscrew it with your fingers. Do not use pliers.
You do not hear it before a flight. Do not fly. Check the battery direction, the lid, and the antenna. Listen again after you think you have switched it off.
The range is short. Hold the receiver elements straight up for a bird on a perch, and flat if the bird is on the ground. If you hear both, use the flat position to pinpoint.