Marantz St-8mkII
¥ 135,000 (around 1980)
Commentary
Quartz lock tuner equipped with traditional gyro touch tuning and oscilloscope.
By applying the accurate reference signal of the crystal oscillation to the original gyro touch tuning, it is equipped with a quartz lock which controls the frequency at every 100 kHz. In addition to the front end, the signal is also detected from the IF final stage to enhance the tuning system.
In addition, the quartz lock employs an electro-touch type that is linked to the gyro-touch knob. When tuning is completed and the knob is released, it locks automatically.
A multi-work oscilloscope replaces the signal meter and the tuning meter.
This oscilloscope can display the precise tuning point, multipath and separation state, and can read the radio wave condition accurately.
You can also connect other devices to the scope and input jacks to monitor the separation characteristics of the deck or amplifier.
A low-noise dual-gate low-noise dual-gate MOS FET to improve performance. The IF stage is divided into a main IF circuit for sound quality and a sub IF circuit for multipath muting to improve both sound quality and reception performance.
In addition, a 4-pole linear phase LC filter and SQW (elastic surface filter) are used in the main section to reduce distortion.
The FM IF circuit has a built-in LC-type anti-noise filter to cut out the excess noise band, enabling playback with improved SN ratio and distortion factor when receiving FM Birdie.
In addition, a PLL pilot canceller circuit is mounted in the MPX stage to achieve stable stereo separation characteristics.
The linearity of the detection circuit is improved by broadening the bandwidth, and the signal-to-noise ratio is improved by using carefully selected silicon diodes.
Model Rating
Type | FM/AM Tuner | ||||
FM Tuner Section | |||||
Receiving frequency range | 76 MHz to 90 MHz | ||||
50 dB quadrature sensitivity | Mono : 14.1dBf/2.8 μ V Stereo : 34.2dBf/28 μ V |
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Chinese arrowhead etting slope | 58dB(20dBf) 64dB(25dBf) 76dB(40dBf) |
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Signal-to-noise ratio | mono:88dB stereo:80dB |
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Harmonic distortion factor |
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Effective selectivity | wide:50dB narrow:90dB |
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Capture ratio | wide:0.8dB narrow:1.2dB |
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Image rejection ratio | 120dB | ||||
Intermediate frequency interference ratio | 120dB | ||||
AM suppression ratio | 70dB | ||||
Frequency characteristic | 30 Hz ~ 15 kHz + 0.2 -1dB | ||||
Stereo separation | 48dB(100Hz) 55dB(1kHz) 45dB(10kHz) |
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<AM Tuner Section> | |||||
Receiving frequency range | 531 to 1602 kHz | ||||
Sensitivity | 10 μ V | ||||
Signal-to-noise ratio | 55dB | ||||
Selectivity | 60dB | ||||
Image rejection ratio | 80dB | ||||
<General> | |||||
Rated power consumption (Electrical Appliance and Material Control Law) | 30W | ||||
Pwer | 100 VAC, 50Hz/60Hz | ||||
External dimensions | Width 474x Height 172x Depth 335 mm | ||||
Weight | 10.3kg |