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RICH OBERMEYER
RICH OBERMEYER 8 uur geleden
Charge and discharge of multicellular lithium batteries: serial For me, an evaluation of the voltage curves at the Balanceran connections would be important to obtain a conclusion on the reliability of the battery pack.
Battery Charger Next Generation: request for comments
AndersG
AndersG 13 uur geleden
Optionally with added noise.   bps = 16; sps = 8000; nsecs = 300; freq_nom = 1000; %1241; %1385; freq_sep = 170; baud = 100; %msg = [0x48, 0x45, 0x4a, 0x21]; % % T H E sp Q U I C K sp B R O W N sp F O X % 74 69 56 5c 2e 4e 4d 1d 1E 5c 72 55 71 27 59 5c 1b 71 3a % % rep rep N A U T I C A L % alpha alpha alpha alpha N A U T I C A L % T H E sp Q U I C K sp B R O W N sp F O X % 74 69 56 5c 2e 4e 4d 1d 1E 5c 72 55 71 27 59 5c 1b 71 3a 5c 5c % 0f 0f 74 69 56 5c 2e 4e 4d 1d 1E 5c 72 55 71 27 59 5c 1b 71 3a %msg = hex2dec({'66','0f','66','0f','66','0f','66','0f','74','0f','69','0f','56','74','5c','69','2e','56','4e','5c','4d','2e','1d','4e','1e','4d','5c','1d','72','1e','55','5c','71','72','27','55','59','71','5c','27','1b','59','71','5c','3a','1b','5c','71','5c','3a','5c','5c'})'; msg = hex2dec({'66','0f','66','0f','66','0f','66','0f','74'})'; % serialise msg into bits % input "msg", output "d" d = zeros(1, length(msg)*7); % NB 7BIT - SKIP MSB! ix = 0; for char = msg for bitcnt = 0:6 % LSB FIRST d(ix+1) = mod((floor(char / (2^bitcnt))), 2); % d(ix+1) = bitget(char,bitcnt+1); ix = ix + 1; end end % Calculate how much the phase is incremented for each sample phase_inc_0 = 2*pi*(freq_nom - freq_sep/2)/sps; phase_inc_1 = 2*pi*(freq_nom + freq_sep/2)/sps; % Preallocate number of sample generated nsamples = sps*nsecs; fsk_signal = zeros(1,nsamples); phase = 0; phase_inc = phase_inc_0; bitcount = 1; for k = 1:nsamples if mod(k, round(sps/baud)) == 1 % Check if current bit is 0 or 1 if d(bitcount) == 0 phase_inc = phase_inc_0; else phase_inc = phase_inc_1; end % Advance to next bit in message bitcount = bitcount + 1; % If end of message, restart from beginning if bitcount > length(d) bitcount = 1; end end fsk_signal(k) = sin(phase); phase = phase + phase_inc; end %wavwrite(fsk_signal, sps, bps, 'audio.wav'); %audiowrite('audio_andax_1241_60s.wav', fsk_signal, sps, 'BitsPerSample', bps); % Create white gaussian noise white=randn(1,nsamples); %*2-1; audiowrite('audio_andax_1k_noise_14 _300s_a.wav', (fsk_signal+white*1.4), sps, 'BitsPerSample', bps);  
Navtex receiver
AndersG
AndersG 13 uur geleden
Attached is a small program that you run in Octave to create an include-file with factors for the digital resonators.   # NAVTEX parameters Fdelta = 170; # BFSK frequency difference Fsym = 100; # Symbol rate F = 1030; %1350; #1241; # Center frequency (1385) # Receiver parameters Fs = 8000; # sample frequency N = Fs/Fsym; # Samples per symbol h_low = cos(2*pi*(F-Fdelta/2)/Fs*(0:N-1)); h_high = cos(2*pi*(F+Fdelta/2)/Fs*(0:N-1)); Bits=16; # Multiply by 32767 and not 32768 to minimise the risc that the largest # positive value ends up as the largest negative Navtex_16bit_Coeffs_lo = round((32767*h_low)); Navtex_16bit_Coeffs_hi = round(32767*h_high); % Write to file F_ID=fopen('C:\\Prog\Mplabx\\DSPTest\\DSPTest.X\\Navtex_filter_coefficients_lo.txt','w+'); fprintf(F_ID, '// ***** MPLAB Navtex filter coefficients for dsPIC *****\n\n'); fprintf(F_ID,'//Frequency %d, high %d low %d\n',F,(F+Fdelta/2),(F-Fdelta/2)); printf("Low\n"); for j=1:length(h_low) fprintf(F_ID, "% 1.8f", h_low(j)); if (mod(j,8) == 0 ) && (j!=80) fprintf (F_ID,",\n") elseif (j!=80) fprintf (F_ID,",") else endif end fclose(F_ID); F_ID=fopen('C:\\Prog\Mplabx\\DSPTest\\DSPTest.X\\Navtex_filter_coefficients_hi.txt','w+'); fprintf(F_ID, '// ***** MPLAB Navtex filter coefficients for dsPIC *****\n\n'); fprintf(F_ID,'//Frequency %d, high %d low %d\n',F,(F+Fdelta/2),(F-Fdelta/2)); %printf("High\n"); for j=1:length(h_high) printf("%d",j); fprintf(F_ID, "% 1.8f", h_high(j)); if (mod(j,8) == 0) && (j!=80) fprintf (F_ID,", \n") elseif (j!=80) fprintf (F_ID,",") else endif end fclose(F_ID);  
Navtex receiver
AndersG
AndersG 14 uur geleden
I have had several users use HPDisk with the HP 85 as well. Unfortunately do I not have access to a HP85 to test, but we were able to iron out small bugs by them sending me log files. Also see this neat mod by Martin Pikryl
HPDisk - An SD-based disk emulator for GPIB instruments and computers
Kargo
Kargo 16 uur geleden
Ladung und Entladung von mehrzelligen Lithiumakkus: seriell Für mich wäre eine Auswertung der Spannungsverläufe an den Balanceranschlüssen wichtig, um einen Rückschluss auf Funktionssicherheit des Akkupacks zu erhalten.
Battery Charger Next Generation: request for comments