SANSUI TU - α 707 Extra
¥ 54,700 (around 1989)
Commentary
An FM/AM tuner with improved quality using an original super-linear system.
The front end is equipped with a SLRC (Super Linear Receiving Circuit) that simultaneously acquires high sensitivity reception capability at weak input and interference rejection capability at strong input.
The antenna input section uses an AGC circuit that employs a PIN diode and a dual-gate MOS FET to automatically carry out optimum gain control according to the input electric field strength, minimizing distortion that occurs in strong electric field areas.
In addition, the IC double-balanced mixer circuit eliminates high-frequency interference and reduces noise.
The IF section is equipped with a WIDE/NARROW band width switching mechanism by SLSIC (Super Linear Selection IF Circuit). For WIDE, a low-distortion wide-band ceramic filter is used. For NARROW, a high-selectivity narrow-band filter with excellent adjacent interference rejection is used.
This makes it possible to receive high-quality signals at a low distortion rate in WIDE mode, while in NARROW mode, interference from neighboring stations in strong electric field regions is sharply cut.
The detection section is equipped with a newly developed SLDC (Super Linear Detector Circuit) for linearly detecting audio signals from FM waves. By incorporating a distortion correction circuit into a VDO (voltage controlled oscillator), linearity over a wide band is achieved.
The digital MPX section is equipped with SLDD (Super Linear Digital Decoder) unique to SANSUI.
Since this circuit carries out demodulation by digital processing, it does not have unnecessary harmonic components that cause demodulation of adjacent stations, and it can perform high-precision stereo demodulation of only the signal of the desired station, thereby greatly improving separation.
In addition, there is no need for an anti-interference filter to cut adjacent station Birdie, and phase and frequency characteristics have been improved.
The power supply unit supplies power to the audio, RF and control systems independently to minimize interference between the stages.
The antenna input has two systems, A and B, and can be switched.
This makes it possible to respond to the direction of arrival of each FM station, enabling optimum reception.
It is equipped with a direct input function that allows you to directly select the desired station by entering the desired frequency with the 10 keys.
It is also equipped with a preset memory that allows one touch channel selection, a memory scan that allows quick selection of preset stations, and a LAST-2 memory function that allows recording of two broadcast stations without a program.
There was a side wood sold separately.
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Model Rating
| Type | Synthesizer FM/AM tuner |
| FM Tuner Section | |
| Practical sensitivity | 10.8dBf |
| SN50dB Sensitivity | mono:16.2dBf stereo:37.0dBf |
| Practical selectivity | wide:60dB narrow:75dB |
| Signal-to-noise ratio | mono:88dB stereo:91dB |
| Distortion Factor (1 kHz) | stereo:0.0095% |
| Separation (1 kHz) | 60 dB or more |
| Image interference ratio | 80dB |
| Spurious interference ratio | 120dB |
| IF interference ratio | 120dB |
| Antenna impedance | 75 Ω |
| Preset memory | 10 stations |
| <AM Tuner Section> | |
| Practical sensitivity | 48dB/m |
| Effective selectivity | wide:30dB narrow:50dB |
| Signal-to-noise ratio | 50dB |
| Distortion factor | 0.3% |
| Preset memory | 10 stations |
| <General> | |
| Rated power consumption | 12W |
| External dimensions | Width 430x Height 98x Depth 315 mm |
| Weight | 5.1kg |
| Sold Separately | Real Side Wood SW-TU1 (¥ 10,000) |