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    Questions about charging lithium batteries (to prolong battery life)

    Hi, I want to know what is the proper methods to prolong lithium battery life: When Should I recharge the battery(at any level 90%, 70 or 40 etc)? Should I charging it fully at 100%? is true that discharging battery below 20% once each month is useful to boost battery life?
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    How to record two signals simultaneous(by using ADC) ?

    i know that i am using the hard way, i do that because my supervisor want me to do that. the main noise is come from electrical 50 Hz, even when i removed it, the noise still large value(about 0.1 to 0.2 V) yes i want to record a row data. yes i understand the aliasing issues , i will...
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    How to record two signals simultaneous(by using ADC) ?

    ok, let me explain: ECG signal is obtained by using preamplifier as figure below: i want to record ECG signal but without using preamplifier, first i will record the two signals come from right and left arms, then inside the computer(by using matlab) i will obtain the ECG signal...
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    How to record two signals simultaneous(by using ADC) ?

    yes i read it, i understand that this chip use one ADC for each channel i am not sure, but may be i need about 1 micro second difference between sampling the two signals not less than 200 Hz. i will search for these questions
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    How to record two signals simultaneous(by using ADC) ?

    OK, if ADC "simultaneous sample and hold" of 20 bits is unavailable: can i use two ADC chips, to record the two signals? can i ensure that the two signals will be sampled in the same time exactly?
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    How to record two signals simultaneous(by using ADC) ?

    Hi: I need to record a two analog signals, by using an ADC(of 20 bits resolution or higher), the two signals are very weak signals of signal to noise ratio about -30 db, so the two signals are very effective by the noise. the problem is : how to record these two signals at the same...
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    Question about turing machine

    that help,thank you:smile:
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    Question about turing machine

    I read information said that: the turing machine can only execute one program the universal turing machine is Re-programmable machine the information here: http://www.cs.rpi.edu/~moorthy/Courses/modcomp/slides/Universal_Turing.ppt
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    Question about turing machine

    yes that help, but if the turing machine can execute any "program", that mean it can simulate any other turing machine , so that mean any turing machine we can called it universal turing machine!!!
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    Question about turing machine

    Hi: I read many articles about turing machine,but i still confused:confused: is a turing machine can only execute one program(hardwired) ? or it can execute many programs(like a conventional computer)? i asking about turing machine as shown in figure blew(not asking about universal TM...
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    A question about Qubit (number of states)

    thank you for this information now i understand how the Qubit works :smile:
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    A question about Qubit (number of states)

    i will give example: if we use the direction of Electron spin to represent the Qubit,spin up= 1 spin down=0 each electron could be spin up and down simultaneously (two states at the same time) but if we have 3 Qubits, we will get a 8 states simultaneously , that mean each Qubit has a 8...
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    A question about Qubit (number of states)

    i don't understand :confused: should i study quantum theory carefully to understand the qubit ? or i just need the basic concept of this theory ?
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    A question about Qubit (number of states)

    Hi I read this information about the Qubit: "N Qubits are equivalent 2^N classical bits (2^N states)" But I couldn't understand that, because I know that each single Qubit could be one and zero at the same time, so each single Qubit is equivalent two classical bits (two states) That...
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    Question about ECG filters

    i use three leads ,one lead is grounded(right lead), my schematic is like(similar) the schematic you put it: http://www.cs.wright.edu/~phe/EGR199/Lab_1/fig3.gif [Broken] i agree with you too:smile:
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    Question about ECG filters

    I read in many book, the ecg lowpass filter is 100 hz cutoff frequency Yes, I think that i also see that 80 Hz cutoff work properly but as i mentioned i am writing a research paper, my work must be agree with a reference book or with another research paper
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    Question about ECG filters

    this is the FFT of ECG signal it very clear that the noise 100 Hz com from power line harmonic sample rate= 400 i am not using anti-alias filter,because the 100 Hz noise i can remove it in matlab yes the frequency of power line in my country is 50 Hz No solution :confused:
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    Question about ECG filters

    ok dear i will do that as soon as, thank you
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    Question about ECG filters

    i use digital filter(matlab) , my hardwere is only preamplifier.
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    Question about ECG filters

    i am not using power supply , i use two batteries (of 6 volt) how can i determine the frequency noise? and how can i prevent it from Interfere with ECG signal?
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    Question about ECG filters

    ok ,this the ECG signal when the cutoff frequency of lowpass filter is 100 Hz and this the ECG signal when the cutoff frequency of lowpass filter is 80 Hz
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    Question about ECG filters

    Hi guys i built an ECG system(preamplifier and filters), but i faced a problem in the filters: the standard of ECG filters is 0.1 Hz cuttoff frequency for highpass filter and 100 Hz for lowpass filter but i only obtain a good ECG signal when i make the cuttoff frequency of highpass filter...
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    Question about design active filter

    NascentOxygen & AlephZero thank you very much
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    Question about design active filter

    hi: i designed an active low-pass filter,but i don't know if it correct method or not i want fc=200 Hz and n(order)=4. i use this method: by let C=100 nF and use this equation "fc=1/(2*pi*C*R1)" i get R1= 8 Kohm,R2=R1 this is for one stage to get filter of 4 order,i repeat that...
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    Why does the ICs(AD620AN) gets damaged?

    jim hardy,yes i live in dry climate thanks for all, i will take your advice .
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    Why does the ICs(AD620AN) gets damaged?

    Maybe this is why ICs gets damaged!! i touched the input lead"input pin" many times and many times the input lead"input pin" was floating, so:if the input pin was floating ,does the IC get dameged? no , the IC has normal temperature ok, i will check it soon thanks....
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    Why does the ICs(AD620AN) gets damaged?

    i like you, i think the problem is from power supply(overvoltage)!!may be! i will check the power supply as soon as.
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    Why does the ICs(AD620AN) gets damaged?

    Hi: I bought six instrument amplifiers(AD620AN), i tested these ICs,all ICs was work properly but later the ICs gets damaged(5 five of 6 ICs gets damaged) i was very carefully(by reading datasheet) about power supply and input voltage i used this circuit(to make AD620AN work as just...
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