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Tap into a totally clean source of AC energy, free from distortion and high-
frequency noise. Revolutionary waveform shaping technology enables highly
precise compensation, providing a pure energy source with 120 V AC ± 2%
(or 230 V AC ± 2%). Audio or video equipment with a total power consumption
of up to 510 VA can be connected, for a drastic improvement in sound and
picture quality. Monitoring of output power, input/output voltage, and input/
output distortion is possible.
The PS-500V is a revolutionary product which
removes the noise components from the AC power
line and improves signal quality by continually
monitoring and shaping the power supply waveform.
As a result, sound and picture quality of audio and
video equipment is drastically improved.
The AC power lines in ordinary homes as well as in
office buildings or recording studios invariably suffer
from high amounts of noise and waveform distortion.
The ideal wavefor m of the power supply is sinusoidal,
but when various electrical devices are connected to
the same power source, unwanted voltage fluctuations
will occur. In addition, appliances containing digital
circuits, such as computers or telephones, emit high-
frequency noise components that can enter audio or
video components via the power supply and severely
affect sound or picture quality by causing
intermodulation noise and distor tion. Only when such
noise interference is removed and totally clean power
is supplied are audio and video components able to
develop their full potential. This is especially true for
high-end equipment. Consequently, upgrading the
quality of the AC power source is bound to result in a
drastic improvement in the overall performance of your
audio/video system.
The PS-500V constantly monitors the input voltage
waveform and adds or subtracts exactly the required
amount of compensation to achieve a perfectly
regular, sinusoidal waveform. The compensation
required by this innovative technique typically is only
a fraction of overall power. The PS-500V therefore
operates with high efficiency and produces little heat,
allowing it to be designed as a fairly compact and
lightweight unit. Because the output impedance of its
AC outlets is extremely low, any combination of
components with a total power consumption of 510
VA maximum can be connected. Since it contains no
oscillators or switching circuitry, the PS-500V itself
does not act as a source of spurious high-frequency
noise.
AC Voltage Stabilizer Based on Waveform Shaping
Technology
The PS-500V accepts AC power on the input side,processes it using internal control circuitry, and
supplies it as clean AC power on the output side. Most
of the AC energy from the input is carried over to the
output. The loss introduced by the PS-500V is very
small, since it consists only of the power required for
waveform compensation. Compared to conventional
AC voltage stabilizers, efficiency is much higher and
excess thermal energy is low, allowing the unit to be
made relatively small and lightweight. Since the power
supply frequency is synchronized to the input, an
inter nal oscillator is not required. Therefore the unititself does not
generate any
high-frequency
noise.
Figure 1 shows a
block diagram of
the unit. The
signal from the
secondary
winding S
1 of the
transformer
reaches the
adding/sub-
tracting circuit
and appears at
the output as
output voltage
(e
0). A par t of the
output voltage is
routed to the -“
input of the
wavefor m
comparator for
wavefor m
comparison. The
S2 signal from
the transformer goes to the reference waveform
generating circuit where it becomes the high-precision
sine waveform (e
i) synchronized to the input frequency
of 50/60 Hz. This sine wave signal is then routed to
the + input of the waveform comparator to be used
as the reference signal. By comparing the two input
signals, a differential component is extracted. Based
on this information, the adding/subtracting circuit can
provide exactly the required amount of compensation
for turning the output into a high-precision sine
wavefor m.
Almost every electrical device used in an household converts the
AC supplied by the outlet into DC current for powering its internal
circuits. This task is performed by a rectifier. As shown in photograph
, the rectifier load current has a pulse waveform with a large
current flowing momentarily in the vicinity of the voltage peak.
This causes a voltage drop, resulting in clipping of the voltage
waveform, as shown in photograph
. A clipped waveform with a
high amount of distortion contains many unwanted frequency
components, or harmonics. When entering the audio circuitry of
an amplifier through the power supply, such harmonic components
can interfere with the audio signal and cause intermodulation
distortion, which has a highly detrimental effect on sound quality.
When passing through the PS-500V, the deformed waveform
is restored to its original sine wave pattern, as shown in
photograph
.
Power supply waveform and PS-500V output waveform
Photo Current waveform of rectified
load
Photo
Voltage waveform of AC line
(distortion approx. 3%)
Photo
PS-500V output waveform
(distor tion approx. 0.2%)
Frequency spectrum of power line
(photo )Frequency spectrum of PS-500V
output (photo )
Frequency spectrum of power line
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Superior Waveform Compensating Power
When the input voltage is 110 V (220 V), the voltage
at the secondar y side of the transformer will also be
110 V (220 V). To bring this to 120 V (230 V), 10 volts
must be added, as shown in Figure 3 (a). Conversely,
if the input is 130 V (240 V), 10 volts must be
subtracted to yield 120 V (230 V), as shown in Figure
3 (b). In actual operation, the peak value of 10 V,
namely 14.1 V is added or subtracted.
Comparing a precise sine wave synchronized to the
input frequency with the output voltage yields a
compensation waveform which is imposed on the
output voltage. Consequently, for an input voltage
range of 108-132 V AC (200-253 V AC) and a constant
load of 510 W, the output voltage is kept constant at
120 V ±2% (230 V ±2%), with a maximum distor tion
ratio of 0.3%. These values demonstrate the
outstanding waveform compensation ability of the
PS-500V.
Note: The above explanation is for the 120 V AC
version of the PS-500V. Figures in brackets refer to
the 230 V AC version.
Highly Effective Interference Rejection
The input side of the PS-500V is
equipped with a line
filter forremoving any high-frequency noise components
present in the power line, such as generated by digital
equipment. The primary and secondary windings of
the power transformer are kept totally separate, and
the fully shielded design shuts out any externally
induced noise.
Since the PS-500V uses the AC feedback principle,
output impedance is extremely low. This prevents any
possibility of mutual interference between components
connected to the outputs of the PS-500V.
Built-in Meter Allows Monitoring of Output Power,
Input/Output Voltage, Input/Output Distortion.
Overload Is Indicated by Flashing Meter Illumination.
The meter of the PS-500V lets the user see at a glance
how much power (VA) the connected equipment is
consuming at any given time. This is especially helpful
for components such as integrated amplifiers or power
amplifiers whose power consumption differs
considerably depending on the volume setting and
actual music signal. The maximum output power rating
of the unit is 510 VA. When this is exceeded, the meter
illumination flashes as a warning indication.
Excellent Current Capability
The power amplifier which performs waveform
compensation is configured as a pure complementary
symmetrical circuit using current feedback forunsurpassed
operation stability.
The output stage
uses transistors
rated for a
maximum current
of 10 amperes.
These devices are
connected in a
10-parallel
complementary
push-pull arrange-
ment, which boasts excellent current capability.
Elaborate Protection Features Assure Total
Operation Safety
When a problem occurs during operation, the circuit
breaker integrated in
the power switch
immediately shuts
off the power, to
protect the unit and
any connected
components.
Assembly with protection
circuitry
Assembly with output stage with 10-
parallel push-pull multi-emitter devices
mounted to large heat sink, waveform
compensation amplifier for addition/
subtraction, comparator for reference
waveform and output waveform,
deviation detector, etc.
Assembly with input voltage/
distortion monitoring circuitry