Without a doubt the
very best way to record SLF ( near dc ) wave forms / signals
is to use excellent preamps / receivers ( as shown on www.vlf.it or Stormwise for example )
directly into your sound card and run programs such as Spectrogram or
Spectrum Lab ( freeware ) to display and collect the wave forms for analysis.
What can you do if your equipment doesn't lend it's self well to the application ?
in my example, I want to use my equipment portable and mobile and I have to
use my older model laptop to run the spectrum analysis software. When I try to use
the receivers / preamps ( mentioned above ) into my laptop , my equipment frequency
response falls off below about 15 hz and displaying and recording SLF waves /
signals below 15 to 20 hz becomes problematic. also, if I wanted to use the current
version of the popular popular spectral program Spectrogram , I could not because it
" demands " a screen resolution higher ( 1024 X 768 minimum ) than the capabilities
of my older model laptop. If your interest are McGreevy style natural earth sounds such
as tweeks, dawn chorus , whistlers etc. , which exist in the 300 to 3000 hz audio range
, then the equipment setup mentioned above would be quite adequate for your interests.
My particular interests were extremely low frequency SLF phenomena below 40 hz and
especially below 15 hz or less. I could have run out and bought a newer model laptop ,
but the " theme " of this site ( and my budget ) being mobile , portable and
" ECONOMICAL " ULF wave hobby applications suggest that I find alternative ,
more affordable ways to get the job done. also , buying a newer laptop would not
be a guarantee that my low frequency issues would disappear.
Interestingly enough, I have discovered that when using a VCO style instrument as the
basic platform for portable / mobile signal work ( see the Gauss Master pages ) , that
you can display the strong audio output vco signal in spectrum programs like spectrogram
and spectrum lab ( see above ) and the vco acts like a translator. one that creates
a spectral display that both contains the vco audio oscillator tone ( the higher
the tone , the stronger the signal ) and contains the AC wave form
component of the signal / wave being recorded / displayed.
for example, the 60hz wall outlet signal from the output of the vco contains the major
vco oscillator sound ( a broad spectrum signal display in the 1500 hz to 3000hz range )
and a clearly displayed 60 hz component that " modulates " the vco signal.
this first spectral display in Spectrum Lab freeware is set to a wide bandwidth of about
1700hz. in this display you can see the bottom half of the main VCO audio wave form.
the ragged edges of this spectral display are caused by the many different signals present
on the input of the Gauss Master ( modded to external antenna, power switch , and
external audio output ) . these signals include a strong local 60 hz presence, and several
other waves.
Among these signals is an interesting 3 - 4 hz unidentified wave, that fades in and out as
it is displayed. ( equipment - modded gauss master, modded < seen else where in
this site> Stormwise IC signal amplifier , and a Stormwise mega ceramic ferrite rod
antenna with 4000 turns of wire ) when using the modded Gauss Master , as above,
you can actually see this 3 - 4 hz signal wiggling the front panel meter at that rate and
hear it in the speaker ( ala Stormwise's ULF IC meter amp ) . the Gauss Master speaker
is quite excellent for hearing the signals present on it's antenna.
this is the same display , except the bandwidth has been set to about 40 hz
to emphasize the low SLF signals. ( my main area of interest. ) this display
clearly shows the unidentified 3 to 4 hz signal that fades in and out .
sometimes , depending upon the particular selection of preamps and antennas I'm using ,
I get a lot of computer hash when I connect up to the computer for recording. you can
often hear it in the Gauss Master or Radio Shack amplifier speaker when it is used in the
" tweeks " configuration, for example. as they suggest on the Stormwise site, I also use
an inexpensive battery powered " baby room " monitor as a wireless link to isolate the
receiving equipment and the spectral computer. this seems to work VERY well when using
VCO audio output . the output of the modded Gauss Master is fed into a modded
( see mod elsewhere on this site ) baby room mic / transmitter and the receiver portion is fed
into the computer sound card. I have to keep the baby monitor receiver antenna " WELL "
away from the computer to keep the computer rf noise from killing the signal into the receiver.
A simple and easy way to document your Gauss Master wave finds and discoveries
setting up and using a laptop computer , both mobile and portable , to document your wave
finds and discoveries is expensive, time consuming and oftentimes cumbersome. it's likely
something for the " enthusiast " but what about something easier and with less equipment ?
I use standard Gauss Master with the audio output mod and a small , inexpensive , digital
recorder in combination to record waves as the Gauss Master finds them . I connect the
audio output of the Gauss Master into the external mike input of the digital recorder to
collect the sounds. set the digital recorder to " VOX " ( voice operated operation )
, set the input level to low so it won't be overloaded by the strong Gauss Master output
and you have a quick and easy way to save your finds.
You will have to keep the recorder away from the Gauss Master , even if it is totally solid
state ( no tape drive motor ) because it will still make RF noises the sensitive Gauss Master
will detect.
This is why I show a longer cord in my picture below. Also , when you place the Gauss
Master in your car or truck, you must find a place where the vehicle computer will not
interfere with the Gauss Master's high ( 1 to 10 MG ) range. I have a SUV and the
overhead compartments work well. I tried my dashboard and it was too noisy for the
Gauss Master. You can put it in the back window or anyplace you can still hear it and
not get computer noise. some recorder's VOX circuits chop off the first part of the
sound, try making your recorder more sensitive ( more mike gain ) or if you find a
MMW , for example, turn around .... hand activate the recorder and drive through the
wave again to record it .
you can feed your recorded VCO sounds into your computer , either as wave files or
directly into the sound card , for spectrogram dispaly and analysis at any convienent time
later on.
this picture shows a complete and working " portable " SLF monitoring station. it has the laptop, Gauss Masters, baby room wireless link, and a 4000 turn Strormwise mega rod antenna housed in the protective ( protect the coil turns from potential damage ) black and white pvc pipe housing. the antenna is mounted on a precision el / az mount to allow the antenna to be tilted and turned to position it to enhance the reception specific signals and / or to exclude others.
is to use excellent preamps / receivers ( as shown on www.vlf.it or Stormwise for example )
directly into your sound card and run programs such as Spectrogram or
Spectrum Lab ( freeware ) to display and collect the wave forms for analysis.
What can you do if your equipment doesn't lend it's self well to the application ?
in my example, I want to use my equipment portable and mobile and I have to
use my older model laptop to run the spectrum analysis software. When I try to use
the receivers / preamps ( mentioned above ) into my laptop , my equipment frequency
response falls off below about 15 hz and displaying and recording SLF waves /
signals below 15 to 20 hz becomes problematic. also, if I wanted to use the current
version of the popular popular spectral program Spectrogram , I could not because it
" demands " a screen resolution higher ( 1024 X 768 minimum ) than the capabilities
of my older model laptop. If your interest are McGreevy style natural earth sounds such
as tweeks, dawn chorus , whistlers etc. , which exist in the 300 to 3000 hz audio range
, then the equipment setup mentioned above would be quite adequate for your interests.
My particular interests were extremely low frequency SLF phenomena below 40 hz and
especially below 15 hz or less. I could have run out and bought a newer model laptop ,
but the " theme " of this site ( and my budget ) being mobile , portable and
" ECONOMICAL " ULF wave hobby applications suggest that I find alternative ,
more affordable ways to get the job done. also , buying a newer laptop would not
be a guarantee that my low frequency issues would disappear.
Interestingly enough, I have discovered that when using a VCO style instrument as the
basic platform for portable / mobile signal work ( see the Gauss Master pages ) , that
you can display the strong audio output vco signal in spectrum programs like spectrogram
and spectrum lab ( see above ) and the vco acts like a translator. one that creates
a spectral display that both contains the vco audio oscillator tone ( the higher
the tone , the stronger the signal ) and contains the AC wave form
component of the signal / wave being recorded / displayed.
for example, the 60hz wall outlet signal from the output of the vco contains the major
vco oscillator sound ( a broad spectrum signal display in the 1500 hz to 3000hz range )
and a clearly displayed 60 hz component that " modulates " the vco signal.
this first spectral display in Spectrum Lab freeware is set to a wide bandwidth of about
1700hz. in this display you can see the bottom half of the main VCO audio wave form.
the ragged edges of this spectral display are caused by the many different signals present
on the input of the Gauss Master ( modded to external antenna, power switch , and
external audio output ) . these signals include a strong local 60 hz presence, and several
other waves.
Among these signals is an interesting 3 - 4 hz unidentified wave, that fades in and out as
it is displayed. ( equipment - modded gauss master, modded < seen else where in
this site> Stormwise IC signal amplifier , and a Stormwise mega ceramic ferrite rod
antenna with 4000 turns of wire ) when using the modded Gauss Master , as above,
you can actually see this 3 - 4 hz signal wiggling the front panel meter at that rate and
hear it in the speaker ( ala Stormwise's ULF IC meter amp ) . the Gauss Master speaker
is quite excellent for hearing the signals present on it's antenna.
this is the same display , except the bandwidth has been set to about 40 hz
to emphasize the low SLF signals. ( my main area of interest. ) this display
clearly shows the unidentified 3 to 4 hz signal that fades in and out .
sometimes , depending upon the particular selection of preamps and antennas I'm using ,
I get a lot of computer hash when I connect up to the computer for recording. you can
often hear it in the Gauss Master or Radio Shack amplifier speaker when it is used in the
" tweeks " configuration, for example. as they suggest on the Stormwise site, I also use
an inexpensive battery powered " baby room " monitor as a wireless link to isolate the
receiving equipment and the spectral computer. this seems to work VERY well when using
VCO audio output . the output of the modded Gauss Master is fed into a modded
( see mod elsewhere on this site ) baby room mic / transmitter and the receiver portion is fed
into the computer sound card. I have to keep the baby monitor receiver antenna " WELL "
away from the computer to keep the computer rf noise from killing the signal into the receiver.
A simple and easy way to document your Gauss Master wave finds and discoveries
setting up and using a laptop computer , both mobile and portable , to document your wave
finds and discoveries is expensive, time consuming and oftentimes cumbersome. it's likely
something for the " enthusiast " but what about something easier and with less equipment ?
I use standard Gauss Master with the audio output mod and a small , inexpensive , digital
recorder in combination to record waves as the Gauss Master finds them . I connect the
audio output of the Gauss Master into the external mike input of the digital recorder to
collect the sounds. set the digital recorder to " VOX " ( voice operated operation )
, set the input level to low so it won't be overloaded by the strong Gauss Master output
and you have a quick and easy way to save your finds.
You will have to keep the recorder away from the Gauss Master , even if it is totally solid
state ( no tape drive motor ) because it will still make RF noises the sensitive Gauss Master
will detect.
This is why I show a longer cord in my picture below. Also , when you place the Gauss
Master in your car or truck, you must find a place where the vehicle computer will not
interfere with the Gauss Master's high ( 1 to 10 MG ) range. I have a SUV and the
overhead compartments work well. I tried my dashboard and it was too noisy for the
Gauss Master. You can put it in the back window or anyplace you can still hear it and
not get computer noise. some recorder's VOX circuits chop off the first part of the
sound, try making your recorder more sensitive ( more mike gain ) or if you find a
MMW , for example, turn around .... hand activate the recorder and drive through the
wave again to record it .
you can feed your recorded VCO sounds into your computer , either as wave files or
directly into the sound card , for spectrogram dispaly and analysis at any convienent time
later on.
this picture shows a complete and working " portable " SLF monitoring station. it has the laptop, Gauss Masters, baby room wireless link, and a 4000 turn Strormwise mega rod antenna housed in the protective ( protect the coil turns from potential damage ) black and white pvc pipe housing. the antenna is mounted on a precision el / az mount to allow the antenna to be tilted and turned to position it to enhance the reception specific signals and / or to exclude others.