Mobile  and Portable wave detection equipment

One particular feature of this  site is   mobile wave hunting and detection
applications that allow the  hobbyist  the advantage of  discovery and documentation
of signals / waves while on the move.  In the case of  coherent  mobile magnetic
waves and  crossover type waves , one must be able to have equipment that easily
moves around  in order to  have " contact " with these waves to find them.  MMWs
 can only  be detected by driving through them and because some types of  MMWs
move around slowly and some types move more quickly , mobility  and / or
portability is  a necessity. This site in interested in SLF  r.f. signals mostly below 45hz.
This mobile and portable  equipment  application is desirable because it also allows
a  hobbyist  the advantage of being able to take super sensitive receiving equipment to
locations far away from  electronic interference and power line hum.

Slow moving " complex " MMWs, for example , seem ( so far ) to  only be  able to be found in
high altitude mountainous areas.  One must be able to take their detection and recording
equipment to the locations where these waves are to be found.  One type of  powerful
" single/s "  magnetic wave seems to be most  prolific in the  coastal areas and may have
an  aquatic  source.  With   " crossover " types of   waves / signals  , because of their
 unusual nature ,  one must be able to have mobile or highly portable equipment to
confirm  that  they are indeed " crossover " types at all.

The equipment featured here is intended to be VERY economical to obtain, modify and use.
There are certainly  expensive  proton magnetometers that could be used in portable
field applications , along with chart recorders and lots of other similar types of field
equipment that could be used as an alternative.   This highly complex  and very expensive
equipment is probably desirable or even necessary for a more detailed and serious scientific
study of these  types of wave phenomena.  Using a Gauss Master , for example , provides
the hobbyist with an inexpensive way to locate MMWS but with the trade off of having to
 be mobile or in motion ( because ac gauss meters have to be moving to detect DC magnetic waves )
when doing it.  This necessity of being in motion isn't  that much of a trade off or inconvenience
because the unusual  mobile nature of these waves requires the wave hunter to be mobile
or portable anyway.  It  actually works out fairly  handily that way.

This picture shows an array of  specialized mobile and portable wave detection equipment
that is economical to build and own.  Except for the GPS , nothing in the picture costs over $130
with most equipment costing under $45.






Another equipment item featured here is the new technology " self resonant " ferrite  rod.  These
types of ferrite rods / magnetic field sensors are interesting because , unlike older  ferrite rods
 as used in a.m. table radios and directional  short wave antennas , they do not depend upon
 external turns of wire to make them resonant on a particular frequency. They can be  " self
 resonant "  at VERY  low frequencies , not require external wires or capacitors and are very
 broadband.  Rods are available that have a super high permeability of  60,000u and are
 broadband " self resonant " between 0  ( zero ) and 3000 hz  ( for example ) .  These rods
 are relatively small and manageable as compared to the  older technology  SLF antennas that
had miles of wire on them and extremely heavy iron  bar cores. These older antennas needed
a truck and a couple of people to transport them. These  new technology  Ferrite rods are easily
managed and transported and WAY less expensive, making  mobile and portable operation easy
 to  accomplish.  These antennas / sensors are  capable of being   extremely  sensitive and
capable of finding / detecting waves / signals 100s or 1000s of miles away.
 The  ferrite rods have performance on par with the older copper wire antennas and can be
easily oriented , elevation / azimuth,  to  facilitate  the directional characteristics of this type of
antenna / sensor to allow a person to " peak " a detected signal / wave to reject other signals
/ waves present or help determine the direction and location of a  signal / wave that is
being received.  This was not practical with the previous , cumbersome , copper wire SLF
antennas / sensors.  Since the rods are " self resonant " and not dependent on turns of
copper wire for resonance , the turns of wire seen on these rod antennas / sensors  are used
 to  " pick  off " the  self resonant signals that are concentrated in these rods. This , much like
 the output coupling loop in a  ref. pi-network tank coil.  The ferrite rods need only  a few
 hundred to a few thousand  ( 4000 turns in the picture below )  turns of wire for the pick-off
coil, rather than the  100,000 turns of a copper wire type SLF antenna / sensor.
   For many years , these large  new technology self resonant ferrite rods were only known
 and used by the military . They were mostly used in classified applications related to long range
underwater  submarine / signal  detection and in satellites as field and wave sensors. Larger rods
  have only been available  to the general public in more recent times. Ferrite rod antennas, when
used portable with preamps and upconverters , must be kept  10 or 15 feet away from a car or truck vehicle.
The computers and other electronic equipment , found in all modern vehicles, can cause severe
interference with the signals  detected with a ferrite rod antenna. ( see equipment picture below )
  A ferrite rod antenna / sensor can easily detect a  small magnet , tossed into the air , from a distance
of  5 to 9 feet away ( completely across a  normal sized room )  they are so sensitive.

( ferrite rod antenna with it's PVC protective outer shell  )


   
Recording , documentation and analysis of waves and signals , portable or mobile is fairly
easily  accomplished in several economical ways.  In both cases of wave / signal detection ,
r.f. direct conversion  ( antennas and preamps connected directly into an audio amplifier
to " hear " signals like earth sounds ... tweeks, whistlers, sferics for ULF r.f. frequencies between
 300 - 3000 hz  ) and  SLF / magnetic wave up conversion  (  antennas and preamps connected into
an  " up converting  "  < so humans can hear / see the wave > device like the Gauss Master  
for frequencies between 0 - 300 hz  and magnetic waves ) three simple and inexpensive methods
are available. 

Digital recorder :
 These days , there are a lot of inexpensive shirt pocket digital audio recorders available.  They
have various amounts of memory and are  easily found places like Ebay  at a very low cost.
They can be connected to the audio output of a direct conversion receiver ( see
" r.f. direct conversion " above ) or the output of a Gauss Master up converter with the
" audio output mod " .  A recorder with lots of memory, selectable recording quality and a
quick operating  " VOX " (  voice operated relay ) circuit are desirable. They are easy to use
in the field and provide a quality  means of capturing your discoveries for storage and analysis ,
later on, at home on your home computer using audio programs like " Spectrogram ".   These
recorders lend themselves well to mobile and portable applications .  Care must be taken
with these types of recorders as all of them generate SLF  r.f.  interference  ( much like the
motor drive in older  tape transport type cassette recorders )  and must be kept well away from
the antennas / sensors of mobile / portable detection equipment.  A ferrite core rod antenna
 with a preamp  and  up converter can hear / detect the electronic " ticks " from one of these
 pocket  digital audio recorders  as much as 5 to 9 feet away, easily .  

This pictures shows a typical ferrite rod antenna / sensor ,  into a signal preamp, into
a Gauss Master up converter , with the audio output connected into an inexpensive
 digital audio recorder.



Laptop computer :

Older laptop computers  are commonly available , nowadays , for  well under $75 .
Like  older outdated  desktop computers they are fairly plentiful.   Laptop computers
lend themselves well to portable and even mobile operation.  Tho, using them  " mobile "
and driving  at the same time can be dangerous !  They can be used " on the fly "
as  audio recorders using programs like " Audacity " and " Recall " , eliminating the need for
a separate digital audio recorder . They are also easily used for signal / wave analysis
as described  here  and on this site !  Keep in mind that nearly all computer sound cards
have a " cut off " below about 15 - 20 hz and cannot hear or record  signals or waves below
this frequency.  Using a " direct input "  ( as in a earth sounds tweeks receiving , mentioned above )
application with a laptop and trying to detect or locate waves / signals
below 15 - 20 hz , like Schumann waves  or geomagnetic type  waves ,  you must use an
 up converter ( like a Gauss Master ) into the laptop audio card. All of the software programs
 mentioned on this site work well with older , simpler computers. A desirable alternative to detecting
and recording / analysis of waves below the 15 - 20 hz cutoff of a typical laptop sound card
might be using  an inexpensive " Dataq " a/d chart recorder set up ( depending upon your needs
and applications )  ! This accessory costs under $25
and is great for seeing and analysis of low frequency waves / signals.

(  this picture is a  laptop computer using the Dataq setup with a ferrite core antenna with the IC preamp
mentioned elsewhere on this site )



This Picture is a typical example of a portable ULF -  SLF / magnetic  wave / signal  detection and
analysis equipment  installation.  In the foreground you can see a large 60,000u ferrite rod
antenna on an old  surplus el / az telescope mount. The the background , in the vehicle opening ,
you can see the laptop ( running spectrogram ) , Gauss Master up converters, digital audio recorder,
and various other equipment items ( as seen in a previous picture ) . There is a LONG cord between
the  ferrite sensor / antenna to  allow it to be positioned well away from the computers in the
vehicle. ( both the laptop and the car's computers / ignition  )   This type of " portable " operation
lends it's self well to " mountain topping " style of operation and to " going where the waves are "
and I don't mean surfing !!! h ah ah aha ha