Hi @parguello,
thanks for sharing your experiments. I see values around 100microV (10^-6 V) in your graph and this range of values looks quite normal to me.
Do you feel like the signal responds to your actions (blink, jaw clenching, occipital alpha) ?
Best,
Julien
@julienConscious said:
Hi @parguello,
thanks for sharing your experiments. I see values around 100microV (10^-6 V) in your graph and this range of values looks quite normal to me.
Do you feel like the signal responds to your actions (blink, jaw clenching, occipital alpha) ?
Best,
Julien
Sorry, perhaps I wasn't clear enough in my previous posts. I'm happy w/ the readings seen in channels 3 - 8, they're all responsive to artifacts, I see alpha waves, and the signals are in the appropriate level signifying successful gain setting. What I'm not so sanguine about is electrodes 1 and 2. As you can see in the recordings, they appear dead. I was wondering if this could be a consequence of running OpenBCI's impedance check on them; did I inadvertently kill them? If this is true, then it's a bigger mystery as to why they're active in OpenBCI GUI but not in BCI2000.
Hi again @parguello,
thanks for the clarification. If they work on the official OpenBCI GUI, it means they are ok. Performing impedance check won't kill the TP. You can try switching them from channels 1-2 to channels 3-4 for instance and see what happens. If they work, the problem is elsewhere (channel is deactivated on BCI2000 for instance). If they don't, check that the electrode is tightly screwed, double check they are correctly powered. Also, the fact that you see a value close to zero on the interface after high pass filtering does not necessarily mean the raw value is zero. It actually means that your raw signal is constant (or oscillating very slowly). If you can access the raw signal, check whether you really get raw values close to zero microV or if you are saturated (constant high absolute value like +/-187 500microV, that would possibly be identical for both channels). If you are saturated, it means the gain is too high on those channels (or was not successfully changed). That was probably what was happening for all channels when you got fV values before you contacted BCI2000 support team. A possibility is that you managed to solve the gain pb for channels 3-8 but possibly not for 1-2 yet.
Best,
Julien
I am reaching out to seek advice regarding an issue we've encountered with the ThinkPulse™ Active Electrode 16-channel Starter Kit. Recently, some of the electrodes began to experience short-circuits. Upon inspection, we discovered moisture in the electronic components, possibly due to perspiration during use.
Our primary concern is understanding whether these electrodes are designed to be resistant to liquids, such as sweat. Unfortunately, the available documentation does not specify their level of liquid resistance.
Has anyone else experienced similar issues with these electrodes? Are there recommended practices to prevent moisture-related problems, or should we consider additional protective measures during usage?
Any insights or suggestions would be greatly appreciated.
I merged your Thinkpulse question regarding moisture and short-circuits into this existing Q&A thread for Thinkpulse. We try to focus all questions on this thread for the benefit of other owners of the Thinkpulse. Mentioning @julienConscious, the developer / inventor.
Hi Juan,
thanks for your question, and thanks William for the mention. Indeed, The ThinkPulse sensors are not designed to be resistant to liquids. The eletronic part is well protected against moisture from the scalp and can tolerate without any problem normal sweat during acquisition. However, ThinkPulse sensors are "dry sensors" and are "active" (contain electronic cicruits): they are not designed to be resitant to any excessive liquid especially coming from the top, high humidity levels during prolonged use or immersion into water. I'm afraid I do not have relevant advice: if you can, try reducing the level of exposition to moisture, otherwise you can always try to seal the hole on the top of the body unit ball casing in case there is a chance water comes from the top but without guarantee it will work. Good luck with your experiment. Best, Julien
I had a lot of trouble getting a good signal with the cyton, whilst trying to use this command: x1040110Xx2040110Xx3040110Xx4040110Xx5060110Xx6060110Xx7060110Xx8060110X
I thought this command would work by batching the PGA Gain setting to x8 for all 8 channels, but the channels would always rail.
The only thing which worked for me was setting each channel PGA Gain sequentially as is done by the OpenBCI GUI.
eg:
Sending config string to board: x1040110X
Sending config string to board: x2040110X
Sending config string to board: x3040110X
Sending config string to board: x4040110X
Sending config string to board: x5040110X
Sending config string to board: x6040110X
Sending config string to board: x7040110X
Sending config string to board: x8040110X
After that was done, I started streaming from the board, but some channels were not giving signal, adjusting the contact of the electrodes allowed them to begin displaying good signal and have a 'Not Railed' value for much longer (sometimes not becoming Railed at all).
I managed to get brainbay working well now, I've only been having trouble with the front electrodes - for some reason I can't get consistently get good signal. The comb electrodes have been working pretty well though! I noticed they seem to have a tighter hold on my skin, so produce less noise at the contact point - they don't move around as much as with the metal electrodes. Here is the change I made to brainbay to break up the config string and send through each channel setting sequentially.
Comments
Hi @parguello,
thanks for sharing your experiments. I see values around 100microV (10^-6 V) in your graph and this range of values looks quite normal to me.
Do you feel like the signal responds to your actions (blink, jaw clenching, occipital alpha) ?
Best,
Julien
Sorry, perhaps I wasn't clear enough in my previous posts. I'm happy w/ the readings seen in channels 3 - 8, they're all responsive to artifacts, I see alpha waves, and the signals are in the appropriate level signifying successful gain setting. What I'm not so sanguine about is electrodes 1 and 2. As you can see in the recordings, they appear dead. I was wondering if this could be a consequence of running OpenBCI's impedance check on them; did I inadvertently kill them? If this is true, then it's a bigger mystery as to why they're active in OpenBCI GUI but not in BCI2000.
Hi again @parguello,
thanks for the clarification. If they work on the official OpenBCI GUI, it means they are ok. Performing impedance check won't kill the TP. You can try switching them from channels 1-2 to channels 3-4 for instance and see what happens. If they work, the problem is elsewhere (channel is deactivated on BCI2000 for instance). If they don't, check that the electrode is tightly screwed, double check they are correctly powered. Also, the fact that you see a value close to zero on the interface after high pass filtering does not necessarily mean the raw value is zero. It actually means that your raw signal is constant (or oscillating very slowly). If you can access the raw signal, check whether you really get raw values close to zero microV or if you are saturated (constant high absolute value like +/-187 500microV, that would possibly be identical for both channels). If you are saturated, it means the gain is too high on those channels (or was not successfully changed). That was probably what was happening for all channels when you got fV values before you contacted BCI2000 support team. A possibility is that you managed to solve the gain pb for channels 3-8 but possibly not for 1-2 yet.
Best,
Julien
Dear OpenBCI Community,
I am reaching out to seek advice regarding an issue we've encountered with the ThinkPulse™ Active Electrode 16-channel Starter Kit. Recently, some of the electrodes began to experience short-circuits. Upon inspection, we discovered moisture in the electronic components, possibly due to perspiration during use.
Our primary concern is understanding whether these electrodes are designed to be resistant to liquids, such as sweat. Unfortunately, the available documentation does not specify their level of liquid resistance.
Has anyone else experienced similar issues with these electrodes? Are there recommended practices to prevent moisture-related problems, or should we consider additional protective measures during usage?
Any insights or suggestions would be greatly appreciated.
Thank you for your assistance.
Best regards,
Juan Araneda
Sigma S.A.
Hi, @JAraneda,
I merged your Thinkpulse question regarding moisture and short-circuits into this existing Q&A thread for Thinkpulse. We try to focus all questions on this thread for the benefit of other owners of the Thinkpulse. Mentioning @julienConscious, the developer / inventor.
William
Hi Juan,
thanks for your question, and thanks William for the mention. Indeed, The ThinkPulse sensors are not designed to be resistant to liquids. The eletronic part is well protected against moisture from the scalp and can tolerate without any problem normal sweat during acquisition. However, ThinkPulse sensors are "dry sensors" and are "active" (contain electronic cicruits): they are not designed to be resitant to any excessive liquid especially coming from the top, high humidity levels during prolonged use or immersion into water. I'm afraid I do not have relevant advice: if you can, try reducing the level of exposition to moisture, otherwise you can always try to seal the hole on the top of the body unit ball casing in case there is a chance water comes from the top but without guarantee it will work. Good luck with your experiment. Best, Julien
I had a lot of trouble getting a good signal with the cyton, whilst trying to use this command:
x1040110Xx2040110Xx3040110Xx4040110Xx5060110Xx6060110Xx7060110Xx8060110XI thought this command would work by batching the PGA Gain setting to x8 for all 8 channels, but the channels would always rail.
The only thing which worked for me was setting each channel PGA Gain sequentially as is done by the OpenBCI GUI.
eg:
After that was done, I started streaming from the board, but some channels were not giving signal, adjusting the contact of the electrodes allowed them to begin displaying good signal and have a 'Not Railed' value for much longer (sometimes not becoming Railed at all).
I managed to get brainbay working well now, I've only been having trouble with the front electrodes - for some reason I can't get consistently get good signal. The comb electrodes have been working pretty well though! I noticed they seem to have a tighter hold on my skin, so produce less noise at the contact point - they don't move around as much as with the metal electrodes. Here is the change I made to brainbay to break up the config string and send through each channel setting sequentially.