Audio Database


108,000yen(August, 1978 release)

FM tuner of a laboratory reference series.

By adopting a CLL scheme original with a Lux, reservation of a high syntony precision and a stability is aimed at to all received frequencies.
By this scheme, it is based on the transmit frequency of the broadcast station controlled by the quartz crystal, and has become a total control system having included even from the front end of a tuner to IF stage and the detection stage. Thereby, it is strong on external requirements, such as a temperature, and the stable reception is enabled.
Since the CLL circuitry has a lock range for securing a capture range for uniting exactly, and a stable receive state in the center frequency of a broadcast station as well as the PLL circuitry which constitutes the feedback loop,If the radio wave of a broadcast station once goes into a capture range and locks this, maintaining the receive state which aligned correctly is continued by work of a powerful feedback circuit. For this reason, even if a drift (gap of a received frequency) arises by transition of external requirements, a feedback starts towards pursuing the transmit frequency of the broadcast station controlled by the quartz crystal, and the stable receive state is acquired.
Since the relock circuitry is built in the CLL circuitry, even if it turns OFF the power source of a tuner, it is not necessary to relock again.

The accu-touch organization is carried so that all the tuning circuits may be united with the center frequency of an exact broadcast station.
The accu-touch organization has detected exact Centrepoint using the control voltage of a CLL circuitry. A mechanical nowait lock is covered now over a tuning knob. If the tuning knob is turned by the usual speed, a knob is locked for about 1 second.

In IF stage, in order to reconcile the outstanding distortion property and the outstanding selectivity property, two steps of IF stage bandwidth switchovers, wide and narrow, are carried.
In the standard wide location, the wide band block filter considered as 2 sets of delay-characteristics serious consideration has realized the low-distortion property. In the narrow location, 2 sets of narrow-band ceramics filters were added, and the high selectivity property is realized.

In order to make front end demonstrate many properties which excelled after IF stage, the 5-unit variable condenser only for FM was adopted, and the selectivity of each RF amplifying circuit was raised, and sufficient stonewalling removal capacity is secured.

The quadrature wide band detection circuitry which low-distortion-izing and a high SN ratio can realize is combined with IF stage. Moreover, the phase response of a low pass filter is improved with adoption of a MPX circuitry with a pilot cancellar.
Furthermore, DC amplifier stream composition is adopted as the audio stage.

Rating of a mode
Form FM tuner
IHF practical speed 1.7 microvolts (9.8dBf)
50dB quieting sensitivity 3.2 microvolts (15.2dBf)
SN ratio 80dB
Frequency characteristic mono, stereo: 20Hz - -17kHz 0.5dB
mono: 0.05% (wide, 100Hz)
0.05% (wide, 1kHz)
0.07% (wide, 6kHz)
0.15% (narrow, 1kHz)
stereo: 0.07% (wide, 100Hz)
0.06% (wide, 1kHz)
0.1% (wide, 6kHz)
0.4% (narrow, 1kHz)
Capture ratio wide:0.8dB
2 signal selectivity (±400kHz) wide:30dB
Spurious characteristics 100dB
IF stonewalling removal ratio 100dB
Image ratio 100dB
Amplitude modulation suppression 62dB
wide: 45dB(100Hz)
narrow: 30dB(1kHz)
An Output voltage/impedance fix: 1V/100 ohm
variable: 0V-1V/100ohm-1.25kohm
Attachment Tuning nowait-lock organization
IF bandwidth switching
The circuitry for a multipath verification
The testing tone circuitry for a sound recording
Center indicator
Signal strength indicator
FM muting circuit
Muting level adjustment
Time muting circuit
Output level control
The coaxial connector for 75 ohm
Supply voltage AC100V, 50Hz/60Hz
Power consumption
(Electrical Appliance and Material Control Law)
Dimensions Width 442x height 101x depth of 400mm
Weight 7kg