Audio Database

Commentary

FM/AM tuner that adopts the D. S. D. C. system.

The MPX section is composed of a combination of two circuit systems, PLL circuit and D. S. D. C. system.
In the D. S. D. C. method, the main switching signal and the auxiliary switching circuit output are symmetrical and opposite in phase, and the leakage signal is canceled by adding the outputs of both switching circuits, and the phase correction circuit is installed so that the phases of the main signal and the leakage signal match.
By combining this with a PLL circuit that suppresses the phase shift between the switching signal and the pilot signal, thereby suppressing the deterioration of separation, we have achieved excellent characteristics.

It has a tuning meter and a signal meter that can be used as a deviation meter or a multipath meter.
A deviation meter can be used to prevent over-input distortion during recording, and a multi-pass meter can be used when the antenna is installed correctly, enabling higher-quality recording.

The preamp section uses ± 2 power supply system, and the audio output circuit uses muting with FET switches to eliminate pop noise during power ON/OFF.
The Rec out uses a low output impedance design with a buffer stage.

The IF stage uses an IC, 5 transistors, and 3 element ceramic filter.
A MOS FET and four variable capacitor are used for the front end section, and a buffer stage with transistors is used for the local oscillation circuit.

Uses a 2-stage carrier leak filter with less ripple in the passband.

M-type coaxial connector is installed to connect 75 Ω cable securely.

Equipped with 4 ch DET OUT terminal.

Multi-path output terminal is mounted.

Equipped with FM muting circuit.

Since around 1975, carrying handles have been sold as a separately sold option.

Model Rating
Type FM/AM Tuner
FM Tuner Section
Receiving frequency 76 MHz to 90 MHz
Antenna impedance 300 Ω equilibrium
75 Ω unbalance
Chinese arrowhead's slope 55 dB (3 μ V)
65 dB (10 μ V)
70 dB (50 μ V)
Sensitivity (IHF) 1.7 μ V
Distortion Factor (400 Hz, 100% modulation) mono:0.15%
stereo:0.2%
Signal-to-noise ratio (100% modulation, 1 mv input) mono:72dB
stereo:67dB
Image ratio 90dB
Selectivity (IHF) 80dB
IF interference ratio 100dB
Harmonic spurious response 100dB
AM suppression ratio 60dB
Capture ratio 1.3dB
Stereo separation 50dB(400Hz)
42 dB (50 Hz to 10 kHz)
Carrier leakage -65dB
Multipath impedance H : 130k Ω
V : 30k Ω
Frequency characteristic 50 Hz ~ 10 kHz + 0 -0.7 dB
20 Hz ~ 15 kHz + 0 -1.5 dB
<AM Tuner Section>
Receiving frequency 520 kHz to 1610 kHz
Sensitivity 20 μ V (IHF)
300 μ V/m (bar antenna)
Distortion factor 0.8%
Signal-to-noise ratio (30% modulation, 1 mv input) 50dB
Image ratio 70dB
Selectivity (IHF) 35dB
IF interference ratio 70dB
<General>
Output Level / Impedance FM (400 Hz, 100% modulation) : 1.5 V maximum / 1.8k Ω
AM (400 Hz, 30% modulation) : 0.15 V maximum / 1.8k Ω
4 ch DET OUT : 0.15V/30k Ω
Multipath output : 0.13 v
Power supply voltage 100 VAC, 50Hz/60Hz
Rated power consumption (Electrical Appliance and Material Control Law) 24W
External dimensions Width 435x Height 157x Depth 300 mm
Weight 8.7kg
Carrying Handle D-9 (1 pair, ¥ 5,000)