FAQ Acquisition
Step 1/5.
power supply
Do you see 50 or 60 Hz interference in the signal.
Reduce mains coupling to get stable recordings.
Quick fixes.
- If possible, use a laptop instead of a desktop PC.
- Disconnect the laptop from mains during recordings.
- Power the HDsEMG device from its internal battery.
- If the device must remain connected to a power source, enable in the Web UI “Battery when acquiring” or “Always from battery”.
- Keep other powered devices and electrical cables at a distance to minimize electromagnetic coupling.
Check.
- Use spectrum or FFT, or the oscillogram, to confirm the 50 or 60 Hz peak.
- If the peak stays high even on battery power, go to the next step.
Why do I see 50 or 60 Hz.
This usually originates from mains power sources through electrical network coupling.
environment
Reduce environmental interference.
Keep the setup away from electromagnetic sources and metallic surfaces.
Avoid placing the device near.
- Power strips, extension cords, or wall sockets.
- Chargers, transformers, or Wi Fi routers.
- Metallic surfaces such as tables, chairs, or floors.
How to isolate.
- Place an insulating layer, such as wood or plastic, between the device and any metal surface.
- Have subjects sit on plastic or wooden chairs, or use an insulating cushion if a metallic surface cannot be avoided.
electrodes and channels
Flat or very noisy channels.
What to do.
- Apply sufficient conductive cream or gel into the electrode foam holes.
- Check that all electrodes are properly connected and in firm contact with the skin.
- Reduce the preamplifier gain from 8 to 4 to increase dynamic range.
Why it happens.
- This usually results from poor electrode skin contact or a strong DC offset.
reference
Is the reference stable and well placed.
Guidelines.
- Ensure the reference strap remains wet throughout the recording.
- Place the reference strap over a bony area with no electromyographic activity, such as wrist or ankle.
If two reference straps are required.
- Place them on the same side of the body, close to the recording site, to minimize loop pickup and unwanted activity.
- Ensure the two straps do not touch each other to prevent interference and ground coupling artifacts.
grids
HDsEMG grid placement and alignment.
Skin preparation.
- Shave and clean the skin thoroughly with an abrasive paste.
- Ensure complete contact by fixing the grid with a cohesive bandage or other fastening systems.
Alignment.
- Align the electrode grid parallel to the muscle fiber direction.
- Proper placement over the target muscle minimizes cross talk from adjacent muscles.
FAQ Realignment
Step 1/6.
concept
Are data acquired from probes through SyncStation automatically realigned.
No, each probe acquires data independently, and realignment is required in post processing.
What Realignment does.
- It uses synchronization pulses sent by the SyncStation, recorded on the buffer channel, to align all probes data and AUX signals.
When you need it.
- Use it when you need correct temporal alignment across different probes and external signals acquired through AUX.
requirements
Do I need extra software for Realignment.
No, Realignment runs directly in OTBiolab and is implemented in Python.
What you actually need.
- OTBiolab with a configured Python environment.
- The Python package installed inside the OTBiolab environment.
Quick check.
- After installation, use the check function to confirm everything is set up correctly.
download
How to download the example Python scripts.
Path in OTBiolab.
- Open “Open Support Window”.
- Go to “Install” under “Python Settings”.
- Download the example scripts, including Realignment.
Verify installation.
- After installation, click “Check”.
- A green tick indicates a successful setup.
where to find it
Where to find the Realignment option.
Open the offline file.
- Go to “Open Offline Window”, then click “Open”.
- Select the signal file that needs realignment.
- You can open otb plus and otb4 files directly.
Select the processing.
- Load the signal.
- Open “Custom Processing” in the left menu.
- Select “Realignment” from the list.
run
How to run Realignment.
Graphical method.
- Open the Realignment process.
- Click the green Start button.
- Wait for completion, depending on data size.
Script Editor method.
- Open Script Editor and the Code Editor tab.
- Run the main.py script.
- Edit code if needed and monitor console output.
results
Where to see results and what to do if it does not work.
Where to find results.
- Results are available in the “Result” tab.
- You can visualize realigned signals and export processed data.
- Check that headers include the “realigned” label.
Troubleshooting.
- Run the software as administrator.
- If using Script Editor, check the error message in the console.
- If the issue persists, open Support Window and contact technical support.
FAQ Trigger
Step 1/6.
overview
What is the Trigger connector.
It is a BNC port on the back panel of the devices, used for synchronization.
What it can do.
- On some devices it can operate as a digital input or as a digital output for synchronization with external systems.
Important check.
- On some devices, such as SyncStation or SyncMini, it works only as an output, as specified on the device label.
- Always check the label before connecting to confirm Input, Output, or both modes.
modes
Trigger as Input or as Output.
Input mode.
- Applicable to desk devices such as Novecento plus and Quattrocento when configured as a digital input.
Output mode.
- Available on desk devices, and also as output on SyncStation and SyncMini depending on the model.
input
How Trigger works as an Input.
The Trigger receives an external signal that can start or stop acquisition in OTBiolab.
Logic levels.
- Logic level 0: voltage below 0.8 V.
- Logic level 1: voltage above 2 V.
Safety limit.
- Do not exceed 5.5 V to prevent damage to the device.
- This mode is used when the device must follow another system timing, for example an external controller or event generator.
output
How Trigger works as an Output.
Desk devices.
- For Novecento plus and Quattrocento, the output indicates OTBiolab acquisition status.
- 0 V means acquisition not active.
- 5 V means acquisition in progress.
Timing accuracy.
- The output is synchronized with bioelectrical and AUX channels.
- Time misalignment between the transition and the first or last sample is less than 2 ms.
syncstation
Trigger on SyncStation and SyncMini.
What the output represents.
- Trigger out reflects the sync pulses sent to the wireless probes.
Relation to probes.
- Each pulse on Trigger output is synchronous with a radiofrequency pulse sent to the probes.
AUX and notes
AUX synchronization and good practices.
Using AUX channels.
- AUX channels can receive signals from other devices for synchronization.
- On desk devices, AUX signals are automatically synchronized with all other data streams.
- On SyncStation base, AUX signals must be manually realigned in post processing.
Operational checklist.
✅ Verify Trigger mode according to your OTBiolab setup.
✅ Never exceed the specified voltage ranges.
✅ Remember that on SyncStation base, AUX signals require manual realignment.
