Category:BiosignalAmplifier - Revision history

Mirage335 at 03:07, 2 September 2016

2016-09-02T03:07:17Z

← Older revision		Revision as of 03:07, 2 September 2016
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	=Usage=		=Usage=
	# Connect the USB port to a computer with the [http://mirage335.~~dyndns~~.org/wiki/Category:BiosignalProcessor BiosignalProcessor] software installed. Primarily, this software depends on [http://www.mega-nerd.com/libsndfile/ libsndfile] and [http://www.baudline.com/ baudline].		# Connect the USB port to a computer with the [http://mirage335-site.member.hacdc.org:6380/wiki/Category:BiosignalProcessor BiosignalProcessor] software installed. Primarily, this software depends on [http://www.mega-nerd.com/libsndfile/ libsndfile] and [http://www.baudline.com/ baudline].
	# Launch the [http://mirage335.~~dyndns~~.org/wiki/Category:BiosignalProcessor BiosignalProcessor] software. Noise floor should be approximately -100dB.		# Launch the [http://mirage335-site.member.hacdc.org:6380/wiki/Category:BiosignalProcessor BiosignalProcessor] software. Noise floor should be approximately -100dB.
	# All sponge electrodes need to be wet, preferably with saline. This includes the reference electrode with a large yellow sponge, and the green sponge electrodes.		# All sponge electrodes need to be wet, preferably with saline. This includes the reference electrode with a large yellow sponge, and the green sponge electrodes.
	# Connect the SATA data cables as shown in the photo. These are actually used as shielded carriers for power and analog signals.		# Connect the SATA data cables as shown in the photo. These are actually used as shielded carriers for power and analog signals.
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	* The BNC analog output on the host board is designed for connection to an oscilloscope.		* The BNC analog output on the host board is designed for connection to an oscilloscope.
	* Signal overload will trigger the green LED on the host board to flash.		* Signal overload will trigger the green LED on the host board to flash.
	* HacDC has a [http://mirage335.~~dyndns~~.org/wiki/BiosignalSimulator BiosignalSimulator] on the test cart, which generates synthetic common-mode and differential-mode signals.		* HacDC has a [http://mirage335-site.member.hacdc.org:6380/wiki/BiosignalSimulator BiosignalSimulator] on the test cart, which generates synthetic common-mode and differential-mode signals.

	=Safety=		=Safety=
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	Additional documentation available on the project's webpage at:		Additional documentation available on the project's webpage at:
	http://mirage335.~~dyndns~~.org/wiki/Mirage335BiosignalAmp		http://mirage335-site.member.hacdc.org:6380/wiki/Mirage335BiosignalAmp

	==Copyleft==		==Copyleft==

Mirage335: /* Status */

2014-02-12T01:51:27Z

Status

← Older revision		Revision as of 01:51, 12 February 2014
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	[[File:Mirage335BiosignalAmplifierHardware.jpg\|right]]		[[File:Mirage335BiosignalAmplifierHardware.jpg\|right]]
	=Status=		=Status=
	Operational~~, major upgrades complete~~. ~~Will return to HacDC Sunday January 26~~, ~~2014~~ .		Operational. Use the dry (gold pin header) electrodes for now, saline electrodes will be sealed in hot glue soon.

	=Usage=		=Usage=

Mirage335: /* Future Improvements */

2014-01-25T03:36:06Z

Future Improvements

← Older revision		Revision as of 03:36, 25 January 2014
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	=Future Improvements=		=Future Improvements=
	* Host board enclosure wasn't quite the right size. Once that is reprinted, all components should be in nice strong 3D printed cases.		* Host board enclosure wasn't quite the right size. Once that is reprinted, all components should be in nice strong 3D printed cases.
	* Surprisingly, saline seems to have leaked into the sponge based active electrodes, possibly due to cracking of certain plastic interfaces. ~~Degraded components~~ will be ~~replaced~~, and the ~~electrode PCBs~~ will be ~~sealed solidly in hot glue~~ this weekend ~~for maximum safety~~.		* Surprisingly, saline seems to have leaked into the sponge based active electrodes, possibly due to cracking of certain plastic interfaces. PCBs will be cleaned, sealed in hot-glue, and the enclosures will be repaired this weekend. In the meantime, the dry electrodes work well as always.
	* Autocorrelation functions would be useful in the BiosignalProcessor software for identifying Event Related Potentials.		* Autocorrelation functions would be useful in the BiosignalProcessor software for identifying Event Related Potentials.

Mirage335 at 03:28, 25 January 2014

2014-01-25T03:28:39Z

← Older revision		Revision as of 03:28, 25 January 2014
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	https://github.com/mirage335/BiosignalProcessor		https://github.com/mirage335/BiosignalProcessor

	Additional documentation available on the project's ~~website~~ at:		Additional documentation available on the project's webpage at:
	http://mirage335.dyndns.org/wiki/Mirage335BiosignalAmp		http://mirage335.dyndns.org/wiki/Mirage335BiosignalAmp

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	[[File:Gplv3-127x51.png]]		[[File:Gplv3-127x51.png]]

			=Future Improvements=
			* Host board enclosure wasn't quite the right size. Once that is reprinted, all components should be in nice strong 3D printed cases.
			* Surprisingly, saline seems to have leaked into the sponge based active electrodes, possibly due to cracking of certain plastic interfaces. Degraded components will be replaced, and the electrode PCBs will be sealed solidly in hot glue this weekend for maximum safety.
			* Autocorrelation functions would be useful in the BiosignalProcessor software for identifying Event Related Potentials.

	=Alternatives=		=Alternatives=

Mirage335: /* Alpha Rhythm */

2014-01-25T01:43:20Z

Alpha Rhythm

← Older revision		Revision as of 01:43, 25 January 2014
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	[[File:BiosignalAmplifierHeartbeat.jpg]]		[[File:BiosignalAmplifierHeartbeat.jpg]]
	==Alpha Rhythm==		==Alpha Rhythm==
	Alpha waves (EEG brainwaves) captured from occipital lobe with eyes closed. Notice the ~10Hz signal.		Alpha waves (EEG brainwaves) captured from occipital lobe with eyes closed. USB output was used directly. Notice the ~10Hz signal.
	[[File:BiosignalAmplifierUSB_Out.png]]		[[File:BiosignalAmplifierUSB_Out.png]]
	Low-frequency noise to the left is expected to go away when a better transformer is used, or electrodes are better positioned.		Low-frequency noise to the left is expected to go away when a better transformer is used, or electrodes are better positioned.

Mirage335: /* Usage */

2014-01-25T01:41:50Z

Usage

← Older revision		Revision as of 01:41, 25 January 2014
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	=Usage=		=Usage=
	# Connect the USB port to a computer with the [http://mirage335.dyndns.org/wiki/Category:BiosignalProcessor BiosignalProcessor] software installed.		# Connect the USB port to a computer with the [http://mirage335.dyndns.org/wiki/Category:BiosignalProcessor BiosignalProcessor] software installed. Primarily, this software depends on [http://www.mega-nerd.com/libsndfile/ libsndfile] and [http://www.baudline.com/ baudline].
	# Launch the [http://mirage335.dyndns.org/wiki/Category:BiosignalProcessor BiosignalProcessor] software. Noise floor should be approximately -100dB.		# Launch the [http://mirage335.dyndns.org/wiki/Category:BiosignalProcessor BiosignalProcessor] software. Noise floor should be approximately -100dB.
	# All sponge electrodes need to be wet, preferably with saline. This includes the reference electrode with a large yellow sponge, and the green sponge electrodes.		# All sponge electrodes need to be wet, preferably with saline. This includes the reference electrode with a large yellow sponge, and the green sponge electrodes.

Mirage335 at 01:30, 25 January 2014

2014-01-25T01:30:58Z

← Older revision		Revision as of 01:30, 25 January 2014
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	[[File:BiosignalAmplifierUSB_Out.png]]		[[File:BiosignalAmplifierUSB_Out.png]]
	Low-frequency noise to the left is expected to go away when a better transformer is used, or electrodes are better positioned.		Low-frequency noise to the left is expected to go away when a better transformer is used, or electrodes are better positioned.

			=Assistance=
			Drop by [irc://irc.freenode.net/hacdc HacDC's IRC channel] and ping mirage335 .

	=Troubleshooting=		=Troubleshooting=

Mirage335: /* Alternatives */

2014-01-25T01:16:30Z

Alternatives

← Older revision		Revision as of 01:16, 25 January 2014
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	HacDC does have three neurosky headsets. Unfortunately, these do not seem to perform well with their built-in dry electrodes. Impedance has been measured at around 3 megaohms.		HacDC does have three neurosky headsets. Unfortunately, these do not seem to perform well with their built-in dry electrodes. Impedance has been measured at around 3 megaohms.

	Texas Instruments supplied HacDC with an ADS1299 EEG biosignal amplifier system-on-a-chip. This device may be within half the performance of this Biosignal Amplifier, offering more channels and greater convenience. Further, the new OpenBCI platform, perhaps the only other decent EEG system worth using, is based on that chip.		Texas Instruments supplied HacDC with an ADS1299 EEG biosignal amplifier system-on-a-chip. This device may be within half the performance of this Biosignal Amplifier, offering more channels and greater convenience. Further, the new [http://www.openbci.com/ OpenBCI] platform, perhaps the only other decent EEG system worth using, is based on that chip.

Mirage335 at 01:14, 25 January 2014

2014-01-25T01:14:04Z

← Older revision		Revision as of 01:14, 25 January 2014
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	* Signal overload will trigger the green LED on the host board to flash.		* Signal overload will trigger the green LED on the host board to flash.
	* HacDC has a [http://mirage335.dyndns.org/wiki/BiosignalSimulator BiosignalSimulator] on the test cart, which generates synthetic common-mode and differential-mode signals.		* HacDC has a [http://mirage335.dyndns.org/wiki/BiosignalSimulator BiosignalSimulator] on the test cart, which generates synthetic common-mode and differential-mode signals.

	~~=Cost=~~
	~~Total cost of replacement is ~$300 and ~60 hours. Please don't break our BiosignalAmplifier!~~

	=Safety=		=Safety=
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	* Try not to leave any of the SATA cables partially connected while the system is on. In theory, the system might be damaged if just one or two of the supply rails (Vcc, GND, or Vee) are disconnected.		* Try not to leave any of the SATA cables partially connected while the system is on. In theory, the system might be damaged if just one or two of the supply rails (Vcc, GND, or Vee) are disconnected.
	* No claim of liability is made by anyone. Your accident is your accident. Use common sense. If you don't understand the safety features and limitations, don't use this circuit.		* No claim of liability is made by anyone. Your accident is your accident. Use common sense. If you don't understand the safety features and limitations, don't use this circuit.

			=Cost=
			Total cost of replacement is ~$300 and ~60 hours. Please don't break our BiosignalAmplifier!

	=Lending Policy=		=Lending Policy=

Mirage335 at 01:11, 25 January 2014

2014-01-25T01:11:20Z

@@ Line 22: / Line 22: @@
 * While sleeping, delta rhythms should appear at 90 minute intervals across the parietal (top of the head) and frontal (forehead) lobes. This has yet to be experimentally verified.
-=Lending Policy=
+=Captured Data Samples=
-Qualified HacDC members are invited to borrow the BiosignalAmplifier, particularly for sleep research. Please update the status section when borrowing. Also be careful to keep all safety concerns in mind.
+==Heartbeat==
 =Troubleshooting=
@@ Line 31: / Line 37: @@
 * Signal overload will trigger the green LED on the host board to flash.
 * HacDC has a [http://mirage335.dyndns.org/wiki/BiosignalSimulator BiosignalSimulator] on the test cart, which generates synthetic common-mode and differential-mode signals.
 =Credit=
@@ Line 55: / Line 76: @@
 [[File:Gplv3-127x51.png]]
 =Alternatives=
-HacDC does have three neurosky headsets. Unfortunately, these do not seem to perform well with their built-in dry electrodes.
+HacDC does have three neurosky headsets. Unfortunately, these do not seem to perform well with their built-in dry electrodes. Impedance has been measured at around 3 megaohms.
 Texas Instruments supplied HacDC with an ADS1299 EEG biosignal amplifier system-on-a-chip. This device may be within half the performance of this Biosignal Amplifier, offering more channels and greater convenience. Further, the new OpenBCI platform, perhaps the only other decent EEG system worth using, is based on that chip.