From: John Morrison (jmorrison_at_ahc.net.au)
Date: 2002-03-03 03:24:02
It does EVERY THING doesn't it. :-)
AND in such a tiny unit.......... WOW
and at such a GREAT price (Though still too expensive for me!!) :-(
John
> -----Original Message-----
> From: Doug Sutherland [mailto:wearable_at_earthlink.net]
> Sent: Sunday, 3 March 2002 1:04 PM
> To: buildcheapeeg_at_yahoogroups.com
> Subject: Re: [buildcheapeeg] More on Pocket Neurobics
>
>
> Abhayamudra Product Specification
>
> EEG SPECIFICATIONS
> ------------------
>
> General 4-ch EEG monitor and neurofeedback with
> integrated Binaural Beat generator, flashing
> LED glasses and binocular rivalry monitor
>
> Channels 4 x monopolar + reference + neutral,
> or 2 x bipolar + neutral (strappable)
>
> A->D Sampling 8.196mSec (~122.07 Hz) Rate
>
> A->D Resolution 10-bit precision, accuracy 9-bits or better
>
> Anti-aliasing Switched capacitor 8th order elliptic filter
> (r=1.2) LPF each channel, fc=programmable
>
> 3dB bandwidth 0.5 - 35/40/44Hz (60Hz countries) selectable
>
> CMRR >95dB
>
> Channel gain V/V: fixed 20k, or independently Ch1/2,
> Ch3/4 10k-40k in 64 steps under ALC
> (+-20%* absolute, +-2% ch to ch)
> (+- 2% absolute to order)
> * digital potentiometer spec
>
> Driven Right Leg Sum of ch common mode, mains hum suppression,
> current limited to IEC 60601
>
> Probe health Measure of 2nd stage dc offset compensation,
> measure each channel separately
>
> Electrodes 6 x 80-160u" silver plated casings surrounding
> saline impregnated sponge
> Expected life: >3 months usage
>
> Connector 8-way Modular
>
>
> BINAURAL BEAT GENERATOR
> -----------------------
>
> General 2048 16-bit unsigned cosine lookup table
> with interpolation
>
> 9 preset, 1 user programmable carrier frequencies,
> 10 preset volume settings (L & R)
>
> 9 preset, 1 user programmable beat frequencies
>
> monaural pink masking noise, 10 preset volume settings
>
> all in up to 8 sequences, each up to 9 minutes in 1
> minute increments, or loop forever
>
> Programmable 0.0 - 999.9Hz, 0.1Hz precision, 0.125Hz accuracy
> Carrier Frequency
> Range
>
> Programmable 0.0 - 99.9Hz, 0.1Hz precision, 0.125Hz accuracy
> Beat Frequency
> Range
>
> Preset Carrier 65.8, 73.6, 165, 197, 246, 393, 440, 492, 526 Hz
> Freqs
>
> Preset Beat 0, 1.2, 4.4, 6.6, 9.9, 13.2, 19.8, 26.3, 39.5 Hz
> Freqs
>
> Pink Noise Pinkish filter - 3dB/octave on white noise
> algorithm (summation of staggered 1st order filters)
> (also 4 octave Voss-McCartney to order)
>
> White Noise Linear congruential (seed=16457)
> algorithm (15-bit linear feedback shift register to order)
>
> D->A Sampling 3.90625 kHz
> Rate
>
> D->A Resolution 8-bit
>
> D->A filtering Switched capacitor 8th order elliptic
> (r=1.2) LPF each channel, fc=1670Hz
>
> Audio 3dB 80 - 1670 Hz
> Bandwidth
>
> Headset > 30 ohms
> Impedance
>
> Audio connector 3.5mm stereo
>
>
> LIGHT GLASSES
> -------------
>
> LEDs 2 x 4 high intensity blue
>
> Modes Left eye - right eye
> Left field of vision - right fov
> (selectable on glasses)
>
> Sync flash - alternate L & R flash
> (selectable on unit)
>
> Connector 4-way modular/3.5mm stereo (I)
> 8-way modular (II)
>
>
> BINOCULAR RIVALRY
> -----------------
>
> Abh II Display Left ocular field - vertical lines moving left
> Rivalry Right ocular field - horizontal lines moving down
>
> Abh I Display Necker Cube
>
> L-R Converging tubes 40mm dia, 33cm long Discriminator
>
> Eye Alternation 0.0 - 2.9 Hz, 0.1 Hz resolution Rate
>
>
> PRESETS
> -------
> 11 (I): setupEEG, focus, relax, release, intuit,
> sleep, theWorks, external, user defined (3 off);
> +2 (II): setup Probes, setup SigGen
>
>
> MODES
> -----
>
> Binaural Beat Probes & feedback tones off
>
> EEG Binaural Beat off, chimes or chords feedback tones
>
> EEG+Binaural Chimes reward only, superimposed on
> Beat Binaural Beat tones
>
> EEG+Beat+Sweep Binaural Beat frequency sweeps between peak
> EEG and target brainwave frequency, L/Rchosen
> dynamically based on lower instantaneous
> threshold value
>
>
> DISPLAYS
> --------
>
> General 64x128 pixel chip-on-glass graphic display,
> menu controlled contrast adjustment
>
> Menus Rolling and scrolling menus and submenus
>
> Probes Display Time domain Ch 1&2 or Ch 3&4, uVolt readout,
> auto scaling analog gain/digital gain with
> readout; linear Y axis, Ch 1&2 or Ch 3&4
> Probes d.c. offset readout
>
> Frequency Frequency Domain 0 - 60Hz , 1/f compensated,
> Display Ch 1&2 or Ch 3&4, log Y axis, auto scaling
> analog gain/digital gain with readout,
> probes status
>
> Mirror Display Left/Right Hemisphere Brain Mirror Ch ½ or
> ¾, Bands: delta, theta1, theta2, alpha,
> beta1, beta2, gamma, pseudo log Y axis,
> R/S ratio values, probes status
>
> Coherency Phase space display of peak reinforce &
> Display suppress band for previous ~120 FFTs Ch 1&2
> or Ch 3&4, R/S ratio values, probes status
>
> Centricity Spatial mean for Ch1 Reinforce band applied
> Display to Ch 1/2/3/4, maker size reflects R/S ratio
> amplitude for each channel, R/S ratio
> values, probes status
>
> Halleys Display Bat length is determined by R/S ratio for Ch
> 1/2/3/4 (left top, left bottom, right top,
> right bottom resp., counts success in
> deflecting ball, R/S ratio values, probes
> status
>
> Binaural Beat Sequence number, left frequency, right
> Display frequency, beat frequency, left volume right
> volume, pink noise level, time remaining,
> R/S ratio values
>
> EEG Log Display Previous 64 smoothed R/S values sampled each
> ~30sec, or Previous 32 logged R/S values
> Ch 1&2 or Ch 3&4
>
> Synchrony Instantaneous & smoothed values of complex
> Display cross-correlation of FFT phasors in Ch1
> reinforce band reflected over Ch1<>2,
> 2<>4,1<>3, & 3<>4, Range - 1.0 to 1.0
>
> Samadhi Display Eyelids response to reinforce band amplitude
> and R/S ratio resp, Ch 1&2 or 3&4, R/S ratio
> values, probes status
>
> Synchrony Log Previous 64 smoothed Xcorel. Values sampled
> Display each ~30sec, or Previous 32 logged Xcorel.
> Values, Ch F&B or Ch L&R
>
> Eye Rivalry Left ocular field - vertical lines moving left
> Display Right ocular field - horizontal lines moving down
> Left-right dominance % readout, eye
> switching rate readout Hz, auto boost flag
>
> Eye Rivalry Log Previous 64 smoothed dominance & sw rate
> values sampled each ~30sec, or
> Previous 32 logged dominance & sw. rate values
>
> Impedance Measurement of a.c. impedance of individual
> (AbhayamudraII electrode-scalp impedances at 30Hz. Range:
> only) 0..125Kohm ± 2K ohm. Auto calibration feature.
>
> Signal Generator 2-tone mode: F1 & F2: 0.0..49.9Hz,
> (AbhayamudraII 0.0..39.9uVpp*, individually settable
> only) Sweep mode: Flo & Fhi: 0.0..49.9Hz,
> 0.0..39.8uVpp*, rate 0..59 seconds
>
>
> PROTOCOL
> --------
>
> General Select reinforce & suppress band for each of
> 4 channels. R&S can be any of delta, theta1,
> theta2, alpha, beta1, beta2, beta3, or
> gamma. R/S calc based on digital filters
> (~65mSec response), X-correlation calcs &
> displays based on FFT (130+mSec response)
>
> Artefact Delta change in Spectral energy measured &
> Suppression compared with threshold -> inhibit rewar
>
>
> DIGITAL FILTERS
> ---------------
>
> General Elliptic 4th order BPF, 2nd order Direct
> Form II cascade implementation with Q15
> format coefficients, 10-bit data
>
> Delta 3dB 0.6 - 3.0 Hz, pass 0.7dB, reject 48dB
> Bandwidth
>
> Theta 1 3dB BW 3.5 - 4.8 Hz, pass 0.1dB, reject 49dB
>
> Theta 2 3dB BW 5.7 - 7.6 Hz, pass 0.1dB, reject 48dB
>
> Alpha BW 8.5 - 10.7dB, pass 0.1dB, reject 48.5dB
>
> Beta 1 BW 11.8 - 15.0 Hz, pass 0.1dB, reject 48dB
>
> beta 2 BW 17.2 - 21.5 Hz, pass 0.1dB, reject 48dB
>
> Beta 3 BW 24.5 - 34.0 Hz, pass 0.1dB, reject 44dB
> (53dB @ 50Hz)
>
> Gamma BW 38.0 - 43.0 Hz, pass 0.1dB, reject 44dB
> (60dB @ 50Hz)
>
>
> FFT
> ---
>
> General 1:N input overlapped, raised-cosine
> windowed, scaling 8-bit Radix2 (8 - 256
> points), 2-ch (Ch A real, Ch B imaginary),
> in-place, complex FFT
>
> Overlap 4:1
>
> Points 64
>
> Window Pseudo Hamming raised cosine
>
> Lookup table 64 point signed 8-bit cosine table
>
> Power Spectrum Pseudo power spectrum using coeff magnitud
> as proxy
>
>
> AURAL REWARD
> ------------
>
> Dynamic Reward triggered by fuzzy logic inference
> threshold engine - inputs are current R/S ratio, R/S
> ratio history, time duration to previous
> reward hit. No manual setup required.
>
> (i) Chords 2048 16-bit unsigned cosine lookup table,
> monaural, Base=440Hz, 3rd=550Hz, 5th= 660Hz,
> 7th=825Hz; ADSR=50/150/600/200mSec resp
> (not available in Bbeat mode)
>
> Algorithm Chord: any 1 R/S->chord 1,any 2->chd 1+2,
> (menu selectable) any 3->chd 1+2+3,all 4->chd 1+2+3+4
> ChordSync: any 1 Xcorel->chord 1 etc
>
> (ii) Chimes .wav files for lo, lo-med, med, med-hi, & hi
>
> Algorithm R/S LF OR LB(L)/RF OR RB(R), LF AND LB(L)/RF
> (menu selectable) AND RB(R)
> Sync: LFLB Xcorel.-> chime1(L),RFRB->chime2(R),
> LFRF->chime3(L+R), LBRB->chime4(L+R)
>
>
> (iii) Continuous Pitch varies in accordance with R/S
> Variable Pitch
>
> Algorithm Left channel: Ch1 or C3; Right channel: Ch2 or Ch4
> Sync: Left channel: Ch LF-RF or Ch LF-LB,
> Right channel: LB-RB or RF-RB
>
>
> ELECTRODE IMPEDANCE METER (Abh II)
> -------------------------
>
> Measurement Inserts 30.5Hz signal into Neutral electrode
> technique and measures individual signals on other
> five electrodes. Current is limited to IEC
> 60601 values plus margin. Measurement is
> sequenced through five electrodes with four
> cycles of 30.5Hz for each measurement ->
> ~0.625 sec for each pass. Two measurement
> points allows discrimination of Neutral &
> other electrode impedance.
>
> Measurement Sum of each of electrodes in series with
> range Neutral electrode < 256K W in 1K W steps.
> (eg if Neutral electrode is 50K W , maximum
> measurement for other electrodes is 205K W )
>
> Accuracy: Uncal: ± 3K W ; Cal: ± 1K W
> Reference
> electrode
>
> Accuracy: Ch1..4 Uncal: ± 4K W ; Cal: ± 2K W
> electrodes
>
> Accuracy: Uncalibrated: unspecified; Calibrated: ± 10K W
> Neutral
> electrode
>
> Calibration Utilises external eeg cable termination (supplied)
>
>
> mVolt SIGNAL GENERATOR (Abh II)
> ----------------------
>
> General Utilises external passive attenuator (supplied)
> Frequency range: sine wave, 0.1..49.9 Hz (Abh II)
> Frequency accuracy: ± 0.1Hz
> Amplitude range: 0.0..39.9 m Voltp-p
> Amplitude accuracy (@ 0.0..30.0uV; 1..49Hz):
> ± 0.5m Voltp-p
> (includes coupling capacitor pre-compensation)
> Amplitude accuracy @ 0.1Hz: -50%
>
> Sweep Mode Single tone of amplitude set 0..40m V
> sweeping between f1 & f2, each selected in
> band 0..50Hz, at a selectable sweep period
> of 0..59 secs. Note some combinations of
> sweep breadth & sweep period will be below
> minimum sweep rate of 0.5Hz/sec causing
> sweep to not proceed beyond f1.
>
> Two-tone mode Two constant tones each individually
> programmed frequency 0..50Hz and amplitude
> 0..40 m Voltp-p
>
>
> INFRARED LINK (Abh II)
> -------------
>
> General Frame consists of sync/data byte + 2/4 channel
> data bytes (Tx & Rx). 6-bit data alternates between
> status & command info. Rx data may add to or replace
> locally generated data, 2 x 9-bit samples in burst,
> then window to receive burst, if no receive then use
> local data
>
> Protocol Pseudo ping-pong, peer-to-peer, Peak wavelength
> 870nm
>
> Rx sensitivity 62.5nA (~40-200nA to order)
>
> Range ~50cm
>
> Format 1 start, 8 data, pseudo even parity*, 1 stop;
> *9th bit: no parity error=0, error=1
>
> Rate 384k Baud
>
> Synchronisation Count 0..3 (prefix of each sync/data byte at
> start of frame)
>
> Status Info Left/Rigth button, Ch1/2/3/4 probe status
>
> Commands Pause/resume, 2/4 ch, ALC on/off, EEG
> local/remote/mix, 8-bit,9-bit(parity) word
>
>
> REAL TIME CLOCK
> ---------------
>
> Format HH:mm (24 hr) DD:MM, auto day of month &
> leap year corrections
>
> Alarm Matching HH:mm; if unit operating-> turn
> off, if off-> resume at previous settings
>
> Accuracy ~± 4min/month (~± 30sec/month to order)
>
>
> TEST MODE
> ---------
>
> General Menu selection of test mode, except for
> strappable selection of left/right earpiece
> tones insertion into Ch 1/2 or ¾ for EEG
> hardware testing
>
> EEG bandwidth 62.5Hz (to observe induced mains hum),
> 1/f compensation removed
>
> Left/Right 7.63/3.815 Hz square wave resp. (to ensure
> earpiece headphones orientation is correct)
>
>
> MULTITASKING DISPATCHER
> -----------------------
>
> Startup thread Power up control
>
> Menu thread Controls scrolling of menus, input of
> config. commands, execution of commands
>
> Main thread Controls main program loop: fft, dig filters
> etc, when unit active
>
> Go thread Controls inputs when unit active
>
> COP thread Controls servicing of watchdog timer when
> unit is active (reset upon software error)
>
> Activity thread Controls unit shut down in absence of
> regular inputs (power save)
>
> Bitbang thread Controls slow serial port control of
> peripherals (dig pot) (noise reduction)
>
> Stop thread Controls power down of unit
>
>
> POWER MANAGEMENT
> ----------------
>
> Power < 100mA @ nom 3.6Vall times, <100uA
> Consumption in power down
>
> Battery 3.6V Nicad, 600mAH
>
> On-time >5 Hrs continuous, >1 month in power down
> (after overnight charge)
>
> Battery life ~ 1 year, regular use, regular charging.
>
> Charging 6-12Vdc >100mA charger, 20mA trickle
> (overnight full charge)
>
> Operational Disable unit upon charging, "Lo-bat" flash,
> measures power down after 5min. idle timeout when in
> startup mode, after 2 min in menu mode,
> after two hours 15min whilst operating,
> "place on charger" warnings
>
> Connector 1.3mm power jack, positive centre pin
>
>
> CASE
> ----
> General Active components fully enclosed by case
> (except connectors) - no exposed metal parts
>
> Material ABS GSM UL rated 94 HB plastic, ~2mm
>
>
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>
This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:39 BST