Marantz ST-50BL
¥ 35,000 (around 1989)
Commentary
A digital synthesizer tuner that thoroughly pursues both reception performance and sound quality.
A dual-gate MOS FET is used for the front end of the pure electronic four stage configuration, especially considering the distortion factor.
This minimizes input distortion and eliminates intermodulation interference and beat interference, resulting in low-noise and low-distortion reception performance.
In addition, the use of a quartz PLL synthesizer ensures accurate reception frequency settings, enabling stable reception.
A ceramic filter with excellent delay characteristics is selected and used in the IF amplifier that amplifies the intermediate frequency, enabling high-fidelity reception and ensuring clear sound quality.
In addition, it is equipped with a switch that can be switched between wide and narrow by a long distance weak electric field and a short distance strong electric field, so it can be used in a wide range of applications.
As well as the IF stage, the detection circuit, which has a significant influence on audio characteristics, employs a unique ultra-wideband ratio detection method.
This eliminates harmonic distortion and realizes wide frequency characteristics.
Two antenna terminals are installed.
Since switching is possible, the channel can be easily selected even when two antennas with different directions are set up.
You can preset up to 20 stations at random, including AM/FM reception band, IF band, mono / stereo FM mode, and antenna switching.
Model Rating
| Type | Digital synthesizer tuner |
| FM Tuner Section | |
| Receiving frequency | 76 to 90 MHz |
| Practical Sensitivity (75 Ω monaural) | 11.3dBf/1.0 μ V |
| SN 50 db Sensitivity | Mono : 19.2dBf/2.5 μ V Stereo : 39.2dBf/25 μ V |
| Harmonic distortion factor (1 kHz) | Mono ・ Wide : 0.08% Stereo ・ Wide : 0.1% |
| Signal-to-noise ratio | mono:85dB stereo:76dB |
| Capture ratio | Wide:1.5dB |
| Execution selectivity | Wide:40dB Narrow:75dB |
| Stereo Separation (1 kHz) | Wide:50dB |
| Frequency characteristic | 30 Hz to 15 kHz, + 0.5 -1.5 dB |
| Image interference ratio | 78dB |
| IF interference ratio | 90dB |
| Spurious interference ratio | 95dB |
| AM suppression ratio | 60dB |
| Subcarrier suppression ratio | 60dB |
| Output level / impedance (100% modulation) | 940mV/1.5k Ω |
| <AM Tuner Section> | |
| Receiving frequency range | 531 to 1602 kHz |
| Practical sensitivity (LOOP) | 500 μ V/m |
| Harmonic distortion factor (1 kHz) | 0.3% |
| Signal-to-noise ratio | 52dB |
| Selectivity | 30dB |
| Image interference ratio | 40dB |
| IF interference ratio | 60dB |
| Output Level / Impedance (30% Modulation) | 280mV/1.5k Ω |
| <General> | |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption (Electrical Appliance and Material Control Law) | 10W |
| External dimensions | Width 420x Height 104x Depth 353 mm |
| Weight | 3.8kg |