Cayman ST-401(403) Non-Linear Junction Detector

The Cayman ST-401 (403) non-linear junction detector (NLJD) is designed to locate hidden electronics by illuminating harmonic responses from semiconductors such as transistors and diodes. It transmits RF energy and displays the returning harmonics so operators can distinguish natural materials from artificial electronic components, helping to find deactivated or active bugs, microphones, cameras, and trackers in places where visual inspection is ineffective.

Key Features & Benefits

• Finds active and dormant devices: Detects electronics whether powered on or off by reading non-linear harmonic responses.
• Material discrimination: Helps differentiate natural semiconductors from artificial structures for fewer false leads.
• Controlled sensitivity: Manual adjustment range with step changes supports precise localisation during close searches.
• Dual indication: Visual LED bars plus audio monitoring provide clear feedback in noisy or quiet environments.
• Field-ready kit: Uses standard rechargeable cells and ships with a shock-proof transport case for protection.

Where It’s Typically Deployed

Use the NLJD for technical security sweeps of offices, boardrooms, mail and parcel screening areas, cargo checks, hotels, private residences, and sensitive facilities. It supports searches of furnishings, walls, and personal effects to reveal hidden electronics that conventional RF or visual checks may miss.

Technical Specifications

• Frequency Range: 2-3GHz
• Maximum Peak Power: Less than 2W
• Antenna: Elliptic
• Operation Modes: "Search", "Audio", "Adaptation
• Sensitivity Adjustment Range(Manual): 40dB (5 Steps of 8dB per adjustment)
• Visual Indication: Three 16 LED Bars
• Audible Indication: Built-in Speaker, and Headphones
• Power Supply: Two Lithium ION Rechargeable Batteries (18650mAH) 3,7V
• Battery-Life: 3-4 Hours (Full Charge - Depending on Operation Mode)
• Charge Time: ~3 Hours
• Dimensions (portable): 300mm x 250mm x 130mm (L*W*H)
• Weight of the Detector: 1.3kg

Packaging Contents

• 1 x Cayman ST-401 Detector
• 4 x Lithium ION Rechargeable Batteries 18650mAh
• 1 x Charging Unit
• 1 x Charger Cable
• 1 x Headphones
• 2 x Test Targets
• 1 x User Manual / User Guide
• 1 x Transportation Shock-proof Case

Frequently Asked Questions (FAQ)

Can it find devices that are switched off?

Yes. NLJDs reveal the non-linear response of semiconductor junctions, allowing detection of powered and unpowered electronics.

How should I interpret the LED bars and audio?

Increasing bar counts and stronger audio indicate a rising harmonic response. Reduce sensitivity as the indication increases to pinpoint the source.

Where should I focus during a sweep?

Scan furniture, wall fixtures, parcels, and dense materials where electronics may be concealed. Use step sensitivity to narrow the location.

What powers the detector and how long does it run?

It uses standard rechargeable 18650 batteries with typical battery life of 3–4 hours per full charge, depending on the operating mode.

Legal Disclaimer

Recording and surveillance laws vary by state and territory. Please check your local requirements, obtain consent where necessary, and use this device only for lawful purposes. This information does not constitute legal advice.

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