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"My God, man! Drilling holes in his head isn't the answer! Now put away your butcher knives and let me save this
patient before it's too late!" Those classic words were uttered by Dr. McCoy in Star Trek IV:
The Voyage Home, after Lt. Chekov (promoted from Ensign after the
TV series) sustained brain damage as a result of falling from a 'nuclear
wessel' when 20th century naval surgeons were about to open his skull to relieve
pressure from swelling. Look at these images from a 1932 article
on using radio waves "to produce protective fever in killing germs of
a number of diseases." 10 to 30 meters was a popular wavelength band
at a power of about 500 watts. The patient's body part to be treated
is placed between the plates to act "as a dielectric" while the liquids
are heated via induced oscillations similar to how a microwave oven
works. How did the doctors know when the treatment was complete? A thermometer
in the mouth was monitored for a temperature rise of about 1 degree
Fahrenheit. Yikes. Anyone out there think that the opinions of a consensus
of 'experts' should never be challenged?
I have been informed by website visitor Eric J. that shortwave
diathermy is still
used in modern medicine! The FCC has allocated shortwave frequencies
13.56 MHz, 27.12 MHz, and 40.68 MHz for its use. Although
the machines are modernized and automated, they fundamentally don't
look a lot different from the ones in the article. I wonder if the new
models include a thermometer for placing in the patient's mouth to monitor
the body temperature rise? Apologies to shortwave diathermyologists(?)
for poking fun at their medieval-looking machines.
How High-Frequency Electric Fields are used in Modern Medicine to Produce
By Irving J. Saxl, Ph.D.
A Patient Undergoing Treatment In this
machine the patient is rolled in blankets and laid upon a rubber
air-cushion between the two large condenser plates. In the right
foreground is the control board for adjusting the machine
Photos Courtesy Amy, Aceves and King
Radio sciences, heretofore used primarily for communication in various
forms, have opened a new field beneficial to humanity. The author tells
of recent investigation in using short radio waves in connection with
their therapeutic effects in raising the body temperature to produce
protective fever in killing germs of a number of diseases
it is possible, with the use of radio waves produced by machines similar
to radio transmitters of the short-wave type, to heat up the human body
and to give it the therapeutic benefit of raised temperature (fever)
in a purely physical way, without the use of chemicals. A new and valuable
tool is thus presented by the physicist to the physician; a clean process
which can be easily controlled without the aid of the drug store and
What is fever? Fever is an increase of the normal
body temperature, together with a general functional derangement, a
higher pulse rate, etc. A body with raised temperature has marked changes
in its metabolism; for instance, it is able to eliminate poisons, destroy
bacteria and other destructive elements of the body at an increased
This is of tremendous importance for maintaining health.
For instance, in a body infected with bacteria, the heat-regulating
mechanism automatically raises the temperature in such a way that the
disease virus finds less favorable living conditions at the new temperature.
But the diseased body cannot always help itself in a sufficient
degree. It has been found necessary in many instances to raise the temperature
of the body by chemical means, e.g., the injection of proteins, malaria
and other germs, which in producing the curative fever often produced
other unfavorable reactions.
Fever in a Limited Area
Radio-Thermic Apparatus in Full View Figure
1. This photograph shows the construction of the high-frequency
tube generator used in the fever machine. At the extreme left
is the step-up transformer. The inductance coil and vacuum tube
are show at center, as well as the sliding frame in which the
condenser plates are let down when not in use.
If there was only a small part of the body which should have been raised
to a higher temperature, it was necessary to heat the entire body, although,
naturally, a limited area can stand a much more severe temperature increase
than a general treatment.
Now radio has made it possible to
heat up the desired limited areas to temperatures far above those obtainable
by chemical means, and under fully controllable conditions.
What is this wonder instrument which can perform these effects, and
how does it work? This so-called fever machine, in its essential parts,
consists of a transmitter similar to a radio transmitter for short waves.
A high-frequency field is generated by this transmitter, but the energy
is not radiated into space by an aerial system, but concentrated between
two or more condenser plates. In this high-frequency field, without
any galvanic contact, the body of the patient is placed, the body acting
as a dielectric between these plates.
Every electric current,
direct current as well as alternating, heats up the body it passes into.
For the body to stand a satisfactory amount of current with an analogous
temperature increase, without undue changes in its physiological and
chemical composition, a high-frequency current has to be used. Only
if frequencies of the order of millions of cycles per second are used
do the excitation of muscular contractions, known as faradization, and
of chemical reactions due to polarization, known as galvanization, cease.
Figure 1 shows a general picture of a so-called fever machine,
or radio-thermic oscillator. The short-wave transmitter is located in
the lower part of the case. The high-frequency oscillations are obtained
from a simple short-wave transmitter which is fed by a push-pull circuit,
delivering about 500 watts.
Two tubes of the vacuum type are
employed, each delivering about 250 watts. About 380 to 400 milliamperes
in plate current is consumed. In the radio-thermic oscillator shown
above two tubes, type 504-A or its equivalent type UV-204-A, are used.
The transmitter works on 110 to 115 volts, alternating current,
of 50 to 60 cycles, and requires about 15 amperes input from the current
The plate voltage is produced by a transformer shown
at the left side of the picture in Figure 1. The high-tension current
is rectified by two full-wave mercury-vapor rectifiers, and the voltage
variations are smoothed out by filters.
The inductance of the
high-frequency circuit consists of about nine windings, with coils of
about 10 inches diameter. The capacity in the transmitter circuit are
the two plates located at the top of the cabinet, and the patient is
placed between them as a dielectric.
The Circuit Essentials
The Oscillator Circuit Essentials Figure
2. The schematic diagram for the push-pull generator used in
perusing the high-frequency currents in the machine developed
by Amy, Aceves and King
This apparatus is about 6 feet long. 36 inches wide and 30 inches high.
The condenser plates slide down into slots without removal. The instruments
for controlling the current intensity and the wavelength at the right
side of the picture) are placed in such a way that they are easily accessible.
This machine delivers about 10 megacycles, corresponding to
a wavelength of about 30 meters. Figure 2 gives a diagram of this machine.
The diagram, together with the data mentioned before, is self-explanatory.
V1 and V2
are rectifier tubes in a full-wave circuit, from which the plate voltage
is taken for the operation of the vacuum tubes V3
and V4. These operate upon
the self-inductance coil L4 in push-pull and create the high-frequency
field applied around the plates of the condenser C10,
between which the patient is placed.
Apparatus of a similar
type is also used by A. Gosset, G. Lakhowsky and others in France, and
by Esau in Jena. The General Electric Company also has entered this
field. Gosset and his collaborators had an adaptable apparatus which
was able to work on wavelengths as short as 2 meters.
is measured by a small oscillating wavemeter circuit, consisting of
an inductance, a condenser and a little flashlight bulb in series with
it. For determining the wavelength, the condenser is turned slowly until
the filament starts lighting. Then the wavemeter is removed as far s
possible, thee condenser being regulated so that the filament of the
lamp just glows.
The exact wavelength of the main radiation
is at that point where the filament just glows up for a single condenser
reading. Care has to be taken not to burn out the lamp by moving the
condenser too quickly while the wavemeter is near the transmitter, as
the increase in power "grows" swiftly as the condenser approaches the
point of resonance.
For working with high sensitivity, the wavemeter
has to be removed from near the oscillator, so that the filament just
shows a faint glow.
The machine developed by Amy, Aceves and
King, Inc., in cooperation with Dr. Ramirez, of the French Hospital,
New York City, uses an air mattress, upon which the patient is laid
between the condenser plates; rubber and air being an excellent insulator,
so that the high-frequency field is not lessened and can work within
the body of the patient.
Method of Treatment
European Type of Apparatus Figure 3. This
fever machine was developed by Professor Esau, and works on
ten meters. The high-frequency field can be concentrated between
the two small condenser plates shown at the end of the treatment
tube. It makes possible a much more intensive treatment with
the short waves over an area of the body that can be kept relatively
For heating up the patient, the entire apparatus, which is on rollers,
is removed from any location near walls which contain steel, as this
naturally would tend to induce high-frequency currents within the structural
material. The patient is rolled in blankets and placed between the condenser
plates. It has proven practical to dress the patient, first, in a woolen
union suit. Thus perspiration is removed automatically and cannot accumulate,
in drops, upon the skin. This is important, as these fluid drops heat
up quicker than the body and cause burns upon the skin ."
position of the patient is important. If we place one hand between
the condenser plates, and the current is put on, the hand will feel
the heat quicker if the hand is held in an imaginary plane which connects
the condenser plates. The temperature increase, however, is less under
equal current conditions when the hand is held parallel to the plates.
This experiment can be performed easiest with one of the small condenser
machines described later in this article. For heating up the patient
more quickly, his feet and shoulders are arranged so that they touch
The apparatus is arranged so that about one
degree temperature increase takes place in 15 minutes, the temperature
being measured by a thermometer in the mouth of the patient. The patient
is heated and kept in his warm blankets after the current has been turned
off. It is interesting to note, in this connection, that the pulse rate
increases for some time after the patient has been removed from the
high-frequency field. The fever does not stop immediately after the
patient is taken out of the condenser. Thus he keeps his "fever" temperature
for several hours. Warm lemonade and tea are given him to replace the
loss of fluid substance and to increase perspiration. If the fever does
not stop by itself after a prescribed time, ice bags are administered.
This method produces less strain on the heart of the patient and is
certainly more effectively controlled by the physician than with quinine
and other chemicals after malaria or protein injections.
showing the temperature increase have been prepared by Dr. Ramirez,
as shown in Figure 4. These also give data for the changes of the pulse
rate and the respiration during the fever treatment.
Blood Pressure and Other Reactions
An Experiment with the Esau Device Figure
5. Mounted between the operating electrodes are glass cells
filled with a fluid resembling body fluids. Thus a study is
made of the effect of high-frequency fields upon a "phantom"
organism. Temperature is recorded; automatically by means of
calibrated electric thermocouples .
There are decided changes which take place in the blood picture of the
treated patient and in his other reactions. Experiments on animals have
been made showing that the temperature returns to normal quite rapidly
as long as the animal has not been heated over 42 degrees Celsius.*
Animals heated above that temperature for a longer period of time have
been killed. A decided loss of weight takes place, ranging from about
two to ten percent of the body weight, according to the length and intensity
of the treatment. Also it makes a great difference whether the sweating
and feverish body is allowed to replenish its loss of water. There are
also marked changes in the different steps of metabolism and in the
non-protein nitrogen of the blood. According to Knudson and Schaible,
this increased in several instances up to 200 percent. Red blood cells
and total white cells are increased too, and, in addition, the microscopic
analysis of the blood shows a number of immature forms of red blood
Figures 3 and 5 show another improved form of machine
for localized fever treatment. This is the machine of Esau and Schliephake,
of Jena. The high-frequency oscillator is entirely built-in within a
metal cabinet connected to the ground, thus protecting the oscillating
circuit from any capacity influence of body parts near it. By using
these small electrodes instead of the large ones, it is possible to
produce fever in a limited area of the body and to avoid the dangerous
and exhausting effects of a general fever even with physical apparatus.
The G. E. Co. has lately produced a fever machine which was
demonstrated at the last convention of the New York Electrical Society,
at the Engineering Auditorium. The plates of this machine are about
twice as large as those of Schliephake, giving a somewhat less localized
With this machine Dr. C. F. Tenney, Jr., attending physician
of the Fifth Avenue Hospital, treated 580 cases of rheumatism since
last April, with results which were so encouraging that several patients
who had come on crutches were able to discard them after a number of
treatments. Whether this fever machine will give a permanent cure in
severe cases of arthritis is still too early to determine. But certainly
the cures already effected are almost as miraculous as the "wonder cures
of the saints." The wonders of the twentieth century are thus seen coming
from the laboratories!
At the short-wave experiments performed in Vienna, the physicians
and other people having to do with the machines during their operation
wear metal-coated laboratory coats and caps. Metal-weave ribbons were
sewed upon the outside of these garments, as electromagnetic frequencies
of this range do not penetrate such shieldings.
Figure 5 shows
an interesting experiment made by Dr. Esau. Between the plates of the
high-frequency generator a number of cells are placed which resemble,
in a rough way, parts of animal tissues. These cells are filled with
a fluid of similar electric characteristics as the cell content of body
tissues. The temperature is controlled automatically in different parts
of the fluid by thermo-elements inserted in the cells. Thus data can
be read directly on the meter on top of the instrument, with reference
to the heating effect of different frequencies under various conditions.
For the mathematical determination of the heating of a body
of primarily dielectric properties it has been found that it depends
primarily from the composition of the electrolyte, from its concentration,
from its size and form and from the wavelength."
the classical field theory of James Clerk Maxwell, the characteristic
wavelength of a body is determined by
Hereby λ the wavelength, ε the dielectric constant
and x the conductivity of the substance. Taking the reciprocal value
of equation (1), we derive the following expression:
In introducing in this equation (2) specific data, Paetzold†
gave the following formula as an expression for the wavelength under
which a body might expect its strongest heating effect:
where f = the frequency (reciprocal to the wavelength)
= the conductivity of the substance (the same as x) l = the length
of the body q = the cross-section of the body a = reciprocal
expression of the various equivalent capacitances involved in the arrangement
k = the dielectric constant of the body (the same as ε)
This means that the characteristic frequency for a substance
has to be high if the dielectric properties of the substance are small.
The frequency will be lower if the substance has a minor electrical
How the Human Body Reacts Figure 4. Diagram
showing the changes in pulse rate, blood pressure, body temperature
and respiration of a woman patient, age 53, who took the radio
There are many other biological applications possible and it may be
expected that the radio sciences will open up a much wider field in
influencing biological tissues than thought of today. For instance,
an experiment has been made in Italy, where caterpillars of the silkworm
were exposed to ultra-high-frequency fields. All of these silkworms
hatched sooner and gave more silk than the untreated ones. However,
this treatment is still too expensive today for practical use.
One of the interesting experiments which have been made with this
ultra-short-wave generator was to place flies in a glass body contained
in ice. Ordinarily these flies died after a very short period of time.
If, however, subjected to the influence of the radio-thermic oscillations,
the flies continued to live in between the ice blocks. At a later date
rooms might be heated with a radio-thermical process, using no caloric
heat production but having the temperature raised in the body as induced
by its dielectric properties in the field of high-frequency oscillations.
At both ends of a room wires or metal plates might be built in in the
walls, filling the space between them with high-frequency energy and
thus heating up the persons in the room between the plates.
The application of radio transmitting apparatus for the science of medicine
promises to be a valuable tool in fighting disease. The application
of radio waves, beginning with ultra-short waves with quasi-optical
characteristics, up to normal short waves of about 30 meters wavelength,
has opened unusual possibilities for the physician and new hopes for
Arthur Knudson and Philip Schaible, Archives of Pathology, Volume II,
pp. 728 to 743, 1931.
** J. Kowarschik: Electrical Short Waves
and Their Importance in Medicine, Wiener Klinische Wochenschrift, Volume
30, pp. 957-962, July, 1931.
† J. Paetzold: The Temperature Increase of Electrolytes
in a High-frequency Condenser Field and Its Importance for Medicine.
Zeitschrift fuer Hochfrequenztechnik, Volume 36, September, 1930, p.