Lutron Ultrasonic Transmitter High Frequency Generator (GS-400) 40kHz

Lutron GS-400 Ultrasonic Transmitter, 40 kHz Tone Generator

The Lutron GS-400 is a companion to an ultrasonic leak detector. It emits a steady 40 kHz tone — inaudible to people, but loud and unmistakable to a detector like the GS-5800. Place the transmitter on one side of a barrier and sweep the detector along the other side, and every gap the sound leaks through shows up as a rising tone and a climbing bar display.

That solves a problem the detector cannot solve alone. A leak detector hears escaping gas, so it needs pressure or vacuum to work with. A door seal, a windshield gasket, a roof penetration or a wall cavity has no pressure behind it — there is nothing to hear. The transmitter supplies the sound, turning any opening into something that can be found from the outside.

Operation is as simple as it sounds: one slide switch, one indicator light, one 40 kHz output. The frequency is derived from a 640 kHz crystal time base divided by 16, so the tone stays stable as the battery ages and readings taken today compare fairly with readings taken next month.

NOTE: The GS-400 is a transmitter only. It produces the test tone and does not detect anything on its own — an ultrasonic detector such as the GS-5800 is required to hear it.

Typical Applications

• Air leaks around door gaskets and seals — place the transmitter inside, sweep the detector around the closed door.
• Air leaks around window seals and sashes.
• Water leak paths in roofs — put the transmitter in the attic or the space below and sweep the roof surface, finding the opening before water ever gets through it.
• Windshield, door and trunk seal leaks on vehicles.
• Conduit and pipe identification — sound the transmitter into one end of a run and trace which conduit or pipe carries it.
• Building envelope and weatherization work, locating infiltration paths without a blower door.
• Enclosure, cabinet and panel seal verification.
• Duct and plenum leak location.

Features

• Steady 40 kHz ultrasonic output for leak path testing with an ultrasonic detector.
• Crystal controlled oscillator — a 640 kHz time base divided by 16 — so the output frequency stays stable.
• Finds openings that have no pressure behind them, which a leak detector alone cannot hear.
• Single slide switch operation.
• Power indicator confirms the unit is running, and warns when the battery needs replacing.
• Compact and light enough to set inside a vehicle, a duct or a wall cavity and leave running.
• Runs on a single 9V battery.

Specifications

• Frequency output: 40 kHz.
• Oscillator circuit: 640 kHz crystal time base, divided by 16.
• Power indicator: LED, lit when the unit is switched on.
• Dimensions: 5.7 x 2.0 x 1.0" (146 x 50 x 26 mm).
• Weight: 4.3 oz (122 g), battery included.
• Operating temperature: 32 to 122 °F (0 to 50 °C). NOTE most batteries are not rated for use below -4 °F or above 125 °F.
• Operating humidity: less than 80% RH.
• Power supply: one 9V (006P, MN1604, PP3) alkaline or heavy duty battery.
• Power consumption: approximately 7.5 mA DC.

Accessories Included

• Operation manual.

Optional Components

• GS-5800 ultrasonic leak detector, 20 kHz to 100 kHz, required to detect the transmitter's output.