Audio Database

TU-S55
Commentary

An FM/AM tuner that improves the sound quality of not only FM but also AM.

The FM section has a servo lock function.
The LED indicates the direction of the deviation. Two lamps light up when the unit is in a just-tuned state. At the same time, the servo lock is engaged. Even if the knob is touched, the lock will not be released to ensure the best tuning.

In the front-end section, an FET with excellent frequency and noise characteristics is used for the top. In addition, a 3-row variable capacitor and a high-Q cap tuning coil are used to realize high sensitivity and high SN.

Double-tune quadrature detector IC is used for the detector, and PLL / MPX / IC is used for the MPX.

Uses an auto-blend circuit that automatically adjusts the amount of blending according to the antenna input level.
By controlling the amount of blending, you can reduce the degradation of separation and increase of noise that occurs with the conventional high blend type.

The AM tuner uses a floating circuit system.
Noise is reduced by completely floating the input of the antenna and the output of the tuner.

Model Rating
Type FM/AM Tuner
FM Tuner Section
Receiving frequency 76.0 mhz to 90.0 mhz
Practical sensitivity (IHF) Mono : 10.5 dB (old IHF, 1.8 μ V)
50 dB quieting sensitivity (IHF) stereo:36.5dBf
Signal-to-noise ratio Mono : 82 dB or higher
Stereo : 77 dB or more
Frequency response (stereo) 30 Hz ~ 15 kHz + 0.3 -1.0 dB
Distortion Factor (IHF, 65 dBf)
mono: 0.08% or Less (100 Hz)
0.08% or Less (1 kHz)
0.08% or Less (6 khz)
stereo: 0.09% or Less (100 Hz)
0.09% or Less (1 kHz)
0.09% or Less (6 khz)
Capture ratio 1.0 dB or less
Selectivity (IHF) 60 dB or More (400 kHz)
Spurious response ratio (IHF) 75 dB or More (83 MHz)
Image Response Ratio (IHF) 50 dB or More (83 MHz)
IF Response Ratio (IHF, Balanced) 85 dB or More (83 MHz)
AM suppression ratio (IHF) 65 dB or more
Stereo Separation (1 kHz) 50 dB or more
Antenna input impedance 300 Ω equilibrium
75 Ω unbalance
<AM Tuner Section>
Receiving frequency 530 kHz to 1600 kHz
Practical sensitivity (IHF, loop antenna) 56dB/m (630 μ V/m)
Selectivity (± 9 kHz) 30 dB or more
Signal-to-noise ratio 45 dB or More (80dB/m)
Distortion factor (30% modulation, 80dB/m) Not more than 0.5%
Image Response Ratio (IHF) 45 dB or More (1000 kHz)
IF Response Ratio (IHF) 35 dB or More (1000 kHz)
<General>
Rated power consumption (Electrical Appliance and Material Control Law) 14W
External dimensions Width 430x Height 76x Depth 272 mm
Weight 3.5kg