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VLF receiver version 2: (2008.07.10:1 vlf#1 tech_notes2#41)

Based on the Nasa INSPIRE VLF-3 receiver. All Gerber files, schematic and Kicad files:

http://1010.co.uk/vlf2.tar.gz

Parts list:

C1         24pF        
C10        10uF        
C11        .1uF        
C12        1uF         
C13        10uF        
C14        330uF       
C15        10uF        
C16        100uF       
C17        1uF         
C18        .1uF        
C19        330uF       
C2         .01uF       
C3         .1uF        
C4         0.01uF      
C5         0.01uF      
C6         .1uF        
C7         .001uF      
C8         .001uF      
C9         .1uF        
D1         3v zener DIODE       
D2         3v zener DIODE       
K1         CONN_3 [headphone out]      
L1         3.9mH       
L2         150mH       
P1         CONN_1 [antenna]      
P2         CONN_2 [power]     
Q1         FET_N (2SK170)       
Q2         NPN (2N2222)         
R1         22M         
R10        20K         
R11        10K         
R12        15K         
R13        270K        
R14        1K          
R15        10          
R16        100         
R17        100         
R18        470         
R19        220         
R2         220         
R20        10k         
R3         220         
R4         43K         
R5         100         
R6         2.2K        
R7         2.2K        
R8         100K - reduce to 10K (less gain) to avoid feedback        
R9         20K         
RV1        10K         
U1         LM358       
U2         LM386       

Further ELF/VLF links:

VLF audio stream: http://www.spaceweather.com/glossary/inspire.html

VLF listener's handbook: http://www.auroralchorus.com/vlfhndbk.htm

http://www.home.pon.net/785/equipment/build_your_own.htm

http://www.vlf.it/fft_beginners/fft_beginners.html

http://istp.gsfc.nasa.gov/istp/polar/polar_pwi_descs.html

http://www-star.stanford.edu/~vlf/ulp_reciv/ulp.htm

http://www.home.pon.net/785/equipment/homemade_b-field_receiver.htm

http://www.da4e.nl/elfspecial.html