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"The time has come for my retirement, don't forget to dream and reach
for the invisible."
"You will be touched ..."
Christopher
Last Update
12.25.07
Theremin Observations
A Theremin Journey of Discovery
"Dedicated to
the theremin pioneers that searched for more."
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This
Theremin Marvel is Lev's Gift
& a Law of Physics
Matching the
Piano Keyboard 12.25.04
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C1 to C4
are spaced
with perfect linearity at three
6 1/2" (16.5 cm) wide octaves.
Sine Sweep with
an ending Trill, try to hear the depth in the rate
of the linearity
Deep
Sine Trill (119k)
- OR - trill-keyboard.mp3
(65k) over 6 octaves at a 40" linear distance
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Make
the
Ultimate Antenna <=Perfect linearity "is"
accomplished with Lev's Antenna
and this is how I made it.
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"The LINKS antenna phenomenon is
the reason these RS Theremin WebPages had to exist, to reveal a better understanding of the "Termen Effect",
to demonstrate Lev's concept of his polyphonic theremin and most important the fulfillment
of one mans dream." Christopher
"LINKS"
Linear Interval of
Notes with Keyboard
Spacing (Theremin notes
matching the exact repeat of a piano's key spacing)
Linear Theremin Antenna Behavior
by Christopher
The mechanism used to swing the theremin's pitch (sound) is
assumed by most to be "Hand Capacitance" between the antenna,
the player and ground. Lev remained silent and
avoided expanding on this incomplete assumption. This kept "Perfect
Linear Pitch" (LINKS)
hidden where
fortunately today in the 21st Century he reveals it in the most unexpected
way.
Why has this perfect linearity
(LINKS)
phenomena gone unnoticed? Did Lev
Termen have an odd sense of humor or was he possibly cautious
about his involvement with RCA? LINKS
"Linear
Interval of Notes with
Keyboard Spacing"
a perfect theremin.
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The Termen Effect
Explore Lev's Antenna,
for perfect linear theremin pitch response
(LINKS)
of up to five octaves.
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"Beyond 4 inches (10cm)
the belief that hand
capacitance controls theremin pitch is a factoid."
This hand-capacitance misnomer
is used for a simple and logical way to explain things!
Beyond 4 inches (10cm) theremin pitch variations are caused from changes in the
"radiation resistance". This is the total RF electro magnetic power radiated divided by the square of the net current flowing into the antenna,
that causes the RF radiation. Can hand-capacitance be
demonstrated as not logical? Make the
$10 Lev Antenna and I will tell you how to adjust the pitch antenna
to create the intervals of the higher notes next to the antenna wider than
notes on the outside 18" away from the antenna, the
low notes. This
all exists in
the same continuous pitch field, in reverse of what hand-capacitance
logic would dictate.
Also
RF hand hoop volume controls can have a better response
range using the Lev antenna tuning principles.
Proper energy distribution and polarization of the antenna's radiation
field creates perfect linearity.
The
number of playable linear octaves is determined by the amount of energy from the pitch oscillator driving
the pitch antenna, not the antenna design specifically.
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Three components influence what is occurring "within" the pitch
antenna. These are inductance, capacitance and
resistance. It is difficult to distinguish
them from one another at high frequencies as their behaviors tend
to blur together.
The closer your hand is to the pitch antenna the denser the available
radiating energy.
The theremin players hand/arm has
less resistance
than the
air space
and the pitch hand absorbs energy into the Thereminist neutral body
mass which behaves as a "neutral reservoir" positioned within the emanating
RF
radiation field. Your body's ability to charge is demonstrated when you scuff your feet on the carpet
then get an electric shock when touching the
kitchen faucet.
Just as the earth is a neutral reservoir to electrical
charge so is your body
mass in a much smaller sense.
It is important for the theremin to have a good earth ground,
this fact is more important than grounding the Thereminist! If the
theremin earth ground is poor you will hear distortion in the
wave shape of theremin pitch. The theremin RF relies on
weak return ground currents and uses the
earth ground as part of the antenna system to accomplish this.
As the Thereminist hand approaches the pitch antenna, an
increase in the
energy transfer
occurs which allows for an increase in the net current
flow into the antenna.
This decreases the
"capacitance-reactance Xc" of the
L1 antenna side pitch oscillator.
This decreased capacitance-reactance has the same effect as increasing the capacitance
in the LC of the pitch oscillator on the pitch antenna side. The end result is the
theremin tone goes higher, simple eh?
Theremin RF
energy transfers near the speed of Light, "instantaneous change"
not really an energy flow.
Dual
LC oscillators that
are typically used in a theremin, tuned to the same frequency
with the coils in proximity and loosely coupled to one another will lock into
synchronization, lightly we hope. This creates the
"null point" where no theremin sound is heard.
Both oscillators are operating as usual, it is just there is no
difference in operating frequency which is the first step in
beating out the theremin tone.
This is also the "zero point"
where the difference in the reactance Xc &
XL of both oscillators
and their component reactance equal zero. The
moment of
breaking the null point is where the theremin demonstrates its
maximum sensitivity.
It could respond to your neutral body mass over two meters away or
lets say 6' to 8'. (Not very useful for music. lol)
The Theremin's audio frequency
(sound) is the frequency difference of the two RF oscillators.
This overall process of heterodyning allows for controlled
audible musical tones,
the Termen Effect.
When perfect pitch linearity occurs
(LINKS)
it's Lev's gift to you. .
. Clara's voice with transistors is a gift to me.
by
Christopher
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Air space implies remoteness from material objects
that could influence the propagation of electromagnetic waves but
includes air and humidity; which effect theremin behavior.
Theremin radiation energy
(Radio Waves) is
absorbed through your hand into your body mass
which acts as a reservoir collecting the RF energy expanding into the air
space from around the antenna. This is why your
large body mass behind your pitch hand has little effect on the pitch. Most of the available energy is
already absorbed through your forward
hand closer to the antenna. Observe the energy fingers in one of those
neon gas globes.
"A theremin operated in the vacuum of outer space would
continually transfer it's maximum
energy through it's dual
electrical/magnetic equilibrium, so the proximity
of your hand would not have any effect on the pitch. Also with no air no sound
(-' ."
If the fixed high frequency oscillator is operating at 1,000,500 hz and the
pitch antenna oscillator is pulled down to 1,000,060 hz the result is a secondary 440 hz
waveform heard as a tone.
This secondary 440 hz waveform can be seen imposed upon the outside edge
of the main oscillator frequency (carrier) using an oscilloscope.
The audio tone is detected and separated from the modulated waveform using a
diode. This very weak audio frequency is then amplified. 440 hz = note A4. Most
of the theremin sound or wave shape, especially the lower frequencies are
based upon
the effective beating of the two magnetic fields
through loose coupling angles in the coils. Diode detection is used to separate
the audio from the RF. It is after diode detection that
other natural analog circuitry is used to enhance the sound.
Notes of Interest:
A critical point to mention is the transistor junctions,
which are affected by temperature change. This is the main
culprit that causes "pitch drift".
Construction imbalances in the two oscillators like one having a trimmer capacitor and the other not
or certain unmatched component
tolerances will make the circuit more susceptible to drift. Pitch drift
is
mostly due from
temperature change or power supply fluctuations. This is why you
should regularly check your tuning during a playing session. The oscillators
can move away from their "null point",
caused predominately from capacitance changes in the circuit
components as they expand or contract due to temperature or voltage change. (Using
matching components
in the oscillator section is always the best!)
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If you're an RF
Enthusiast and you experiment with the unique Lev
Antenna, I would like to post your opinion why Lev's perfect
linearity occurs. Your clarity or a "different" perspective would be greatly appreciated.
Christopher
02.01.07
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Excellent Read
Mark Barton's
Observation of Antenna Linearity
(07.20.07)
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Why has this perfect linearity
(LINKS)
phenomena gone unnoticed? Did Lev
Termen have an odd sense of humor or was he possibly cautious
about his involvement with RCA? LINKS
"Linear Interval of Notes with Keyboard Spacing"
theremin@oldtemeculaX.com
<=Remove X from
your Email Address
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RS Theremin Conclusion: The Ultimate 2 operates as a basic
AM Radio Transmitters with a tuned control
antenna and a complimentary beat frequency oscillator. Radio waves
radiate from an electrically excited antenna, and ripple outwards near the speed of light. The controlled external transfer of energy
travels across the air (dual
electrical/magnetic equilibrium) which has a direct effect on the
"radiation resistance" within
the antenna. This has a direct effect on the "capacitance reactance" of the pitch oscillator.
This is not some circular path from the theremin => to the Thereminist
=> to the ground => back to the theremin. This is
electro-magnetic energy transferring out the theremin antenna forever!
Anyone who has sincerely explored the hand-capacitance theory
soon realizes the math breaks down.
As a matter of fact you begin to fudge, then close your eyes and assume
the pieces of the puzzle fit.
All of my webpages are a collection of my
thoughts and what I have observed. Though I demonstrate
several
phenomena's, some will remain unexplained so others might enjoy
searching for treasure in the sandbox.
Christopher
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Her name is Simplicity.
The circuit board is mounted under the center bracket.
Simplicity
Up Close & Personal
The full height of the vertical bamboo
area has linear behavior.
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Yes, this can be done!
"Placing note A2 just under thirteen inches (33 cm)
distance from A4 is
ordinary, but to place note A3 dead center between them is a
law of
theremin physics that startled me when it revealed itself. Interestingly,
Lev has held this
marvel of Linear Interval of Notes with Keyboard Spacing "LINKS" close to the vest." Christopher
12.25.04
The Ultimate
Antenna
As you move your own fingers
forward on the paper keyboard strip in the picture, all 24 notes,
three octaves C1
138.6
hz - C4
1108.7
hz will measure "perfect" when
validated with a pitch tuner. You can still go beyond A5
3.52 khz
approaching the antenna.
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C2
246.9hz - C5 2093hz
can also match 6.5" Linear Interval of Notes with Keyboard Spacing "LINKS". This line of play is directly
at the pitch antenna.
01.07.05
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This Lev Antenna works in a perfectly tuned balance with my Ultimate
2; which is a "true heterodyne
theremin" operating at
1000 kHz. An
Original Relaxed Theremin Sound
rstheremin_pure_voice3.mp3
(238k)
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"Those of you that read the
"Vision" and
wondered where all this was heading over the past year, for me it has been
the journey few experience in their lifetime. There are no words that
capture the "Vision". The main theremin
components are now revealed on my WebPages. Have a wonderful and creative New Year
my friends". Christopher
12.25.04 |