Support Center

The FOTRIC TD Series uses an array of 64 MEMS microphones that capture sound from multiple directions at once. When a sound is made, it reaches each microphone at a slightly different time. The device calculates these tiny time differences to determine exactly where the sound is coming from, then overlays the sound source location as a colorful heatmap on the live camera image.

In simple terms: it lets you "see" where sounds are coming from — even sounds that are too quiet or too high-frequency for the human ear to hear.

The device is passive — it only receives sound waves, it does not emit any signals, so there is no radiation concern.

This is a known issue with early TD2 units. When the battery level drops below 20%, the device may not charge through the USB-C port or power on.

Solution: Use the charging dock that came with your TD2. Remove the battery from the device, place it into the charging dock, and let it charge for a few hours. Once charged, reinstall the battery and the device should operate normally.

If your TD2 did not come with a charging dock, please contact us and we will send you one free of charge.

Note: This issue has been resolved in newer production units.

If your TD2e is not charging or powering on, please try the following:

1. Remove the battery from the device
2. Place the battery into the charging dock and let it charge for a few hours
3. Reinstall the battery and try powering on

If this does not work, please contact us with your order number and a short video showing how the device behaves when you try to power it on and charge it. This will help our technical team identify the issue quickly.

If you are experiencing a black screen, severe lag, or visual artifacts when using the TD2 Geek with your phone, this may be a software compatibility issue with certain phone models.

The TD2 Geek requires an Android phone with Android 12 or above and OTG function enabled. Please make sure these are met first.

If the requirements are met and the issue persists, please contact us with your phone model and order number. Our technical team will investigate and provide a solution.

Known issue: Some Xiaomi models running HyperOS have a confirmed compatibility issue. A fix is currently under development.

This is one of the most common questions and it comes down to sound frequency.

The FOTRIC TD Series (TD2 / TD2e) detects sound across a wide range of 2kHz to 100kHz. This range covers both the upper end of audible sound and the ultrasonic range where most industrial signals (gas leaks, mechanical faults) occur.

So why can you hear something but the device doesn't show it?

If you hear a low-pitched or mid-range sound (below 2kHz), it falls outside the device's designed detection range — the camera is optimized for higher-frequency signals, and this is working as intended. Most everyday ambient sounds fall into this category.

However, if you hear a high-pitched hissing or squealing sound, there is a good chance the device can detect and locate it, as these sounds often have frequency components that fall within the 2kHz-20kHz overlap zone.

The key takeaway: The TD Series is designed to detect the high-frequency signals produced by industrial issues like gas leaks, mechanical faults, and electrical anomalies. Low-frequency everyday sounds are outside its intended detection range, which is normal for this type of instrument.

This is normal and expected. Compressed gas leaks and other industrial sound sources naturally produce ultrasonic signals. The ultrasonic range (20kHz+) has lower background noise, making detection cleaner and more reliable.

Even when a leak produces an audible hissing sound, it also generates ultrasonic components that the device detects and locates. So whether a leak is audible or not — as long as it produces ultrasonic signals (which most pressurized leaks do), the device can detect it.

Results appearing in the ultrasonic range simply mean the device is picking up the cleanest signal available in that environment.

The effective detection distance depends on the model and the sound source:

• TD2 / TD2 Geek: 0.3m to 100m
• TD2e: 0.3m to 60m

Can it detect sounds closer than 0.3m? Yes, sounds within 0.3m can be detected. However, due to the near-field effect, the alignment between the microphone array and the visible-light camera decreases at very close distances, which may result in less accurate positioning.

Can it detect sounds farther than the rated distance? Under certain conditions, yes. Sound sources with very high sound pressure levels (e.g., a jet engine at high altitude) can be detected at much greater distances.

Yes. The TD Series is designed for use in industrial environments (non-explosive areas). In noisy settings, you can adjust the following to improve detection:

• Frequency range: Adjust to filter out background noise and focus on the target sound's frequency
• Noise Suppression Mode: Filters out low-level sounds to reduce environmental interference
• Acoustic Image Focus: Focus on a specific region to minimize surrounding noise
• Sound source mode: Switch between Single-source, Multi-source, or All-source mode as needed

With the right settings, the device can effectively isolate and locate target sounds even in loud environments.

Yes. Vacuum and negative pressure leaks can be detected using the same principle as positive pressure leaks. The escaping gas (now entering the system) creates turbulence that generates sound waves within the detectable frequency range.

Tip: Position the device at a 45° to 90° angle relative to the suspected leak point. Smaller angles may not receive the acoustic signal effectively.

Gas leak detection with the TD Series is not dependent on the gas type. As long as the leak generates sufficient sound pressure (audible or ultrasonic), it can be detected. This applies to compressed air, refrigerants, natural gas, and other pressurized gases.

Note: In certain environments (e.g., chemical Zone I/II, mines), explosion-proof rated equipment may be required. The TD Series is not explosion-proof.

Not directly. The TD Series detects airborne sound waves. Water leaking inside a wall or underground does not produce sufficient airborne ultrasonic signals for the device to detect.

However, if a water pipe is exposed and a leak is present, pressurized water escaping can generate detectable sound.

For wall-pipe leaks: A thermal imaging camera (e.g., FOTRIC thermal cameras) is a better choice, as it can detect temperature differences caused by moisture in the wall.

No. The TD Series detects sound waves that travel through air. Walls and solid barriers block or absorb these sound waves, preventing the device from detecting sound sources on the other side.

The default settings are a starting point. For best results, adjust the frequency range based on what you're trying to detect.

1. Adjust the frequency range — Don't rely on default settings. Set the range according to your target (see table above).
2. Maintain proper distance — Stay within the effective range. Avoid positioning too close.
3. Use Noise Suppression Mode in noisy environments — This filters out background noise for more stable imaging.
4. Use the right detection mode:
   • Single-source Mode — Focus on the strongest sound source only
   • Multi-source Mode — View up to 3 sound sources simultaneously
   • All-source Mode — Full scan of the area, no limit on sound source count
5. Use Acoustic Image Focus — Masks surrounding areas to focus on a specific region.

The TD2 and TD2e cover 2kHz to 100kHz. This range covers most common applications:

• Gas leak detection — typically 20kHz–40kHz ✅
• Applications above 100kHz — ❌ These are beyond the device's detection range

If you are unsure whether the device is suitable for your specific application, please contact us before purchasing. We can help you determine if this product is the right fit, and if not, recommend a more suitable alternative.

The warranty covers manufacturing defects under normal use conditions.

The TD2 and TD2e include a standard power adapter that supports 100V~240V AC, making them compatible with power outlets worldwide. The device also supports charging via USB Type-C (5V).

This is normal and not a defect. The TD Series processors continuously calculate acoustic data from all 64 microphones in real time, which generates heat. The device is designed with heat dissipation built into the side label areas, so these areas will be warmer than other parts of the device during use.

No. The TD2e does not support PRPD pattern analysis.

The dB value displayed on the screen represents the Sound Pressure Level (SPL) detected at the measurement distance. It is a measure of the acoustic signal's intensity at the device's position, not a percentage or a simple "loudness" value.

These values are useful for comparing the relative intensity of different sound sources during inspection.

Yes, under the right conditions. The TD2e can detect refrigerant leaks from air conditioning systems.

Tips for best results:

• Detection distance: Start at approximately 1 meter from the suspected leak point
• Pressure matters: Detection works best when the system is pressurized (e.g., 2MPa in heating mode). Pressurizing or holding pressure before testing improves results
• Sensitivity threshold: For context, a leak producing at least 1 bubble every 3 seconds in water is detectable
• Background noise: Placing sound-absorbing material (e.g., sponge) behind the pipe can help reduce noise interference

The acoustic images saved as JPG files do not contain raw acoustic data and cannot be further analyzed in PC software. They are visual records of what was detected at the time of capture.

For on-device analysis, you can use the built-in gallery to review and analyze captured images directly on the device.

The TD2e complies with the following international standards:

The TD Series has an IP54 rating, meaning it is protected against dust ingress (limited) and splashing water from any direction. This makes it suitable for use in industrial environments, but it should not be submerged in water.

Yes. Compressed air leak detection is one of the most common applications for the TD Series. The device can quickly locate leaks in compressed air systems, pipelines, and fittings without the need for soap spray or contact methods.

Recommended frequency range: 20kHz - 40kHz for best results.