DENON TU-950
¥ 49,800 (around 1985)
Commentary
FM/AM tuner equipped with SSS (Super Searcher system).
SSS is a system developed to eliminate RF intermodulation interference without affecting the quality of radio waves to be received. It consists of a newly developed band suppress circuit built into the antenna input section and a noise level indicator that displays the interference level. This circuit is a filter that rapidly attenuates one of the strong input radio waves that cause spurious signals. The attenuation frequency can be changed by the SSS controller.
When interference occurs, the SSS is turned ON and the controller minimizes the noise level, eliminating interference and enabling clear reception.
The front-end section consists of a high voltage varactor diode (equivalent to a four string varistor) and a dual gate MOS FET.
In addition, the S/N ratio is improved by setting the comparison frequency of the PLL that locks the tuning frequency to 25 kHz, which is out of the audible band.
We have improved various characteristics by adopting a static control method for the frequency-display circuit, an IF stage that can be switched between wide and narrow, a ceramic filter with constant delay characteristics (when IF is wide), a pilot canceler, and an anti Birdie filter.
Four tuning methods are available : eight FM / AM one touch random preset tuning, auto tuning, manual tuning, and last channel memory tuning.
It is equipped with a quality indicator that the LED gives a green sign in good reception.
This indicator does not light when sufficient SN ratio cannot be obtained due to insufficient input of radio waves or RF intermodulation interference. Therefore, it can be used for antenna and interference check.
A loop antenna is installed to improve AM sensitivity and S/N.
Built-in oscillator for recording level check.
Model Rating
| Type | FM/AM Tuner |
| FM Tuner Section | |
| Receiving frequency | 76 MHz to 90 MHz |
| Antenna terminal | 75 Ω (Terminal Type) |
| Practical sensitivity | 0.9 μ V/10.3 dBf |
| S/N50dB sensitivity | Stereo : 21 μ V/37.7 dBf Mono : 1.8 μ V/16.4 dBf |
| Image interference ratio | 90dB |
| IF interference ratio | 100dB |
| AM suppression ratio | 65dB |
| Effective selectivity | Wide : 50 dB (± 400 kHz) Narrow : 60 dB (± 300 kHz) |
| Capture ratio | 1.0dB |
| Frequency characteristic | 20 Hz to 15 kHz + 0.2 -1.5 dB |
| Signal-to-noise ratio (weight A) | stereo:82dB mono:88dB |
| Total harmonic distortion rate (1 kHz) | Stereo : 0.04% at 90% modulation Mono : 0.03% (at 100% modulation) |
| Stereo separation | 57dB(1kHz) |
| Output level | 0.6 v (at 100% modulation) |
| <AM Tuner Section> | |
| Receiving frequency | 522 to 1,611 kHz |
| Antenna | Terminal type with loop antenna |
| Practical Sensitivity (S/N20dB) | 18 μ V |
| Selectivity | 50 dB (± 9 kHz) |
| Image ratio | 45dB |
| Signal-to-noise ratio | 55dB |
| Total harmonic distortion factor | 0.3%(1kHz) |
| Output level | 0.2 V at 30% modulation |
| Level check Signal | |
| Frequency | 440 Hz sine wave |
| Output level | 0.3 v (at 50% modulation) |
| <General> | |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 11W |
| External dimensions (including knob, leg and terminal) | Width 434x Height 66x Depth 281 mm |
| Weight | 3.6kg |