|53,000yen(around the 1973 time)
The FM/AM tuner which adopted high-integrated IC
equivalent to 203 elements, and the phase linear ceramics filter.
front end part, the dual gate MOS FET of a low noise is selected carefully, it
is adopted as RF stage and the mixer stage, and practical speed is raised.
Furthermore, radio-interference exclusion capacity is raised by the tuning
circuit which uses a 4-unit variable condenser.
The buffer circuitry is
established in the local oscillator circuit, also when the office where field
strength is strong adjoins, it drew by work of a buffer circuitry and the event
with an unstable event etc. is prevented.
Original IC for IF which
summarized 203 elements to one with the technology of Pioneer is adopted as the
Furthermore, it excelled in the linearity over the wide band in
the detection circuitry, and little quadrature detection is adopted.
Moreover, the phase response in a passband was thought as important and the
phase linear ceramics filter is adopted.
The SCA beat interference and
the separation were coped with, high-integrated IC is adopted as a MPX
circuitry, and the property is improved by adoption of a double balance type
differential demodulation scheme.
Moreover, since the low pass filter which
cuts a harmful remains carrier (19kHz and 38kHz) is used, the carrier leakage
has also decreased.
The ceramics filter is adopted as IF stage of AM
tuner part, a sharp slope property is acquired with moderate bandwidth, and the
modification of selectivity and a tone quality is measured.
stability at the time of a strong input is raised by adoption of high-integrated
IC developed only for AM.
Furthermore, there is no distortion in a local
oscillation wave at adoption of a balance type mixer, and the spurious
characteristics is also good.
The AM section is also improving the image
stonewalling ratio and IF stonewalling ratio by adoption of the 1 step of
aligned type RF amplification which uses a triple variable condenser.
The muting circuit is carried, the transitional pop noise at the time of
tuning stops by the double action effect by the combination of semiconductor
switching and a reed relay, and the unpleasant shocking noise at the time of a
syntony is stopped.
The signal meter of a new method is adopted.
input signal is taken from each limiter stage, and an input signal until it
results in the Dainyuu power from a small input is correctly followed for the
scheme which adds a signal with a sufficient linearity to meter in a loose curve
through detection and direct-current amplifier with a level detector.
The amplifier for headphone has adopted the OTL amplifier of a
Darlington connection, and a loudness level of sound can be controlled in the
It is used, when the multipath termination is carried and
the fewest orientation of an antenna of the cross interferencee by the multipath
reflection of an elastic wave is chosen.
By connecting stereo display-device
subset-dependency-100 and an oscilloscope, the best point of the orientation of
an antenna can be searched for easily.
The MPX noise filter which omits
a noise at the time of a reception of FM stereophonic broadcasting is carried.
The output-terminal carries a fixture and two variable lines, and FM and
AM can adjust independently the Output voltage of a variable output-terminal.
||AM/FM stereo tuner
|<FM tuner part>
||One step of MOS FET RF, a 6 steps of 4-unit
variable condenser limiter
|Practical speed (IHF)
|Capture ratio (IHF)
|Effective selectivity (IHF)
|Image stonewalling ratio (82MHz)
||90dB or more
|IF stonewalling ratio (82MHz)
||100dB or more
|Spurious stonewalling ratio
||100dB or more
|AM supression ratio
||mono: 0.2% or less
stereo: 0.4% or less
|Frequency characteristic (stereo)
||20Hz-15kHz+0.2 -2.0 dB
||1kHz : 40dB or more
50Hz-10kHz : 30dB or more
|Carrier leakage supression ratio
||300-ohm balance type
|MPX noise filter
|<AM tuner part>
||1 step of aligned type RF triple variable
|Practical speed (IHF, bar antenna)
|Practical speed (IHF)
|Image stonewalling ratio
||65dB or more
|IF stonewalling ratio
||85dB or more
||Ferrite bar-antenna adjunct
|An Output voltage/impedance
||Fixed: 650mV / 4.7kohm
Variable: 70mV -
Headphone: 150mV (8ohm)
|The semiconductor used
||Transistor: 19 pieces
FET: Two pieces
IC: Four pieces
Diode, others: Nine pieces
||Power-switch un-interlocking.: One line
||Width 430x height 138x depth of 345mm