TRIO KT-700
¥ 39,800 (around 1982)
Commentary
AM/FM tuner with TRIO's unique clean reception filter.
A clean reception filter is used to eliminate harsh high-frequency beat interference caused by adjacent interference waves generated by intermodulation during stereo reception.
The high-frequency separation is also improved by the improvement of the filter circuit.
A newly developed low-noise quadrature detection IC is adopted, and the SN ratio is improved while maintaining a wide demodulation band by making the IC device itself low-noise.
An independent FET muting circuit is used to suppress noise generated during tuning, detuning, or power ON/OFF.
Together with noise-detecting muting, which cuts out the deep TV buzz that occurs during tuning and detuning, it realizes clear stereo playback.
A two stage linear phase type high-selectivity ceramic filter with excellent phase linearity is used for the IF band filter.
In addition, the differential amplifier circuit has a total of eight stages, two outside stages and six inside stages of the IC, and is designed to resist adjacent channel interference.
The front end section is a high-frequency amplification 1-stage 3-series varicon structure using a low-noise J-FET with excellent high-frequency characteristics.
A hybrid circuit is used for the MIX and local oscillator circuit to improve the stability.
The built-in REC CAL (test signal generation circuit) transmits the CAL signal at a stable level so that the recording level can be adjusted.
It uses a 2-color lighting tuning / lock indicator that reads tuning and detuning automatically and displays with LED (light emitting diode).
When the tuning knob is turned to enter the tuning range of the receiving station, the Tune/Lock LED turns red. Moreover, when the knob is released from the touch servo mechanism, the servo lock automatically differentiates to keep the best tuning point. At this time, the LED turns green to indicate the locked state.
The signal meter that indicates the antenna input is a 5-point LED display for both FM and AM.
A high-selectivity ladder-type ceramic filter is used in the AM receiver to improve adjacent interference rejection and frequency characteristics.
Model Rating
| Type | FM/AM stereo tuner | ||||
| FM Tuner Section | |||||
| Receiving frequency range | 76 MHz to 90 MHz | ||||
| Antenna impedance | 300 Ω equilibrium 75 Ω unbalance |
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| Sensitivity (75 Ω) | 0.95 μ V (IHF), 10.8 dBf (new IHF) | ||||
| SN ratio 50 dB sensitivity | Mono : 2.0 μ V (IHF), 17.2 dBf (new IHF) Stereo : 20 μ V (IHF), 37.3 dBf (new IHF) |
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| Harmonic distortion factor (100% modulation) |
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| SN ratio (100% modulation, 85 dBf input) | mono:84dB stereo:78dB |
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| Capture ratio | 1.5dB | ||||
| Effective selectivity | 65dB | ||||
| Stereo separation | 52dB(1kHz) 40 dB (50 Hz to 10 kHz) |
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| Frequency characteristic | 30 Hz to 15 kHz + 0.2 -1.5 dB | ||||
| Image interference ratio (84 MHz) | 55dB | ||||
| IF / Spurious Interference Ratio (84 MHz) | 95dB/90dB | ||||
| AM suppression ratio / subcarrier suppression ratio | 60dB/42dB | ||||
| <AM Tuner Section> | |||||
| Receiving frequency range | 520 kHz to 1650 kHz | ||||
| Sensitivity (IHF / loop antenna) | 15 μ V / 250 μ V/m | ||||
| Signal-to-noise ratio (30% modulation, 1 mv input) | 52dB | ||||
| Harmonic distortion factor (1000 kHz) | 0.4% | ||||
| Selectivity (IHF) | 58dB | ||||
| <Output Level / Impedance> | |||||
| FM (1 kHz, 100% Dev.) | Fixed : 0.75V/1.8k Ω | ||||
| AM (400 Hz, 30% Mod.) | Fixed : 0.15V/2k Ω | ||||
| <General> | |||||
| Rated power consumption | 10W (Electrical Appliance and Material Control Law) | ||||
| Pwer | 100 VAC, 50/60Hz | ||||
| External dimensions | Width 440x Height 78x Depth 390 mm | ||||
| Weight | 4.7kg | ||||