TRIO KT-1000

Commentary

Following KT-9900 and L-01T, an FM/AM tuner equipped with a pulse count in the detection part and a sampling hold in the MPX part.

The MPX section is equipped with a new sample-hold MPX that cancels beat interference from the SCA band without using an SCA filter.
The Sample-and-Hold MPX uses a pulse with no time width as a switching waveform and captures only the time with the maximum amplitude. This method does not mix in extra information such as distortion and improves the separation characteristics.
In addition, unlike conventional switching systems, it does not require a circuit for improving separation consisting of NFB and operation amplification, and achieves an excellent low distortion factor.
In addition, it has the following features : "stereo demodulation efficiency is approximately 30% higher than that of conventional switching systems and an excellent S / N ratio", "dynamic carrier leakage due to changes in the modulation level of voice hardly occurs", "static carrier leakage is suppressed to almost 0 by using an active filter and a pilot canceler using an operational amplifier", "instantaneous voltage changes are little, so the slew rate of the amplifier in the latter stage is little problem and distortion is little", and "since the input and output stages are driven by ± power supply from the input stage to the output stage, all input and output stages are directly connected and DC amplification is possible".

It is equipped with a new pulse count system composed of two newly developed ICs from the IF part to detection.
The system IC with built-in peripheral functions enables rational placement and realizes an FM demodulation system that can display the characteristics of pulse counting.

The RF circuit has a 2-stage switching function.
When the direct conversion system is selected, the input from the antenna is directly input to the mixer without RF amplification, and excellent two signal characteristics, high SN ratio and dynamic range are obtained.
In addition, the normal position is designed with high sensitivity so that sharp reception is possible even at small power stations.

It is equipped with an independent power source oscillator adopted in the L-01T. By separating the power source from the detector and MPX, mutual interference via the power source is prevented.

In order to prevent popping noise during tuning and detuning, we have adopted the Roman グニファイ system, which automatically detects that the hand has been released from the knob after tuning and extends the spectrum to ultra-low frequencies.

The AM tuner uses two stage switching of the IF band.
In the wide position, a wide-band ladder filter with sharp attenuation characteristics is adopted to improve sound quality. In the area where radio wave conditions are unfavorable, a low position with an emphasis on selectivity characteristics is selected, and adjacent interference is eliminated by a 4-element ladder filter and a 2-element ceramic filter.

High sensitivity is obtained by using a large loop antenna of 160x100mm for AM.

It is equipped with a servo lock mechanism to improve the tuning accuracy. By using the tuning knob as a sensor, it locks accurately when the tuning knob is released after tuning.

Model Rating

Type	FM/AM Tuner
FM Tuner Section
Receiving frequency range	76 MHz to 90 MHz
Antenna impedance	75 Ω unbalance
Sensitivity (75 Ω)	Normal (75 Ω) : 10.3 dBf (New IHF) / 0.9 μ V (IHF) Direct (75 Ω) : 23.3 dBf (New IHF) / 4.0 μ V (IHF)
SN ratio 50 dB sensitivity	Normal (mono): 16.4 dBf (New IHF) / 4.0 μ V (IHF) (stereo): 29.3 dBf (New IHF) / 1.8 μ V (IHF) Direct (mono): 37.3 dBf (new IHF) / 20 μ V (IHF) (stereo): 49.5 dBf (New IHF) / 83 μ V (IHF)
Harmonic distortion factor (100% modulation)	mono stereo Wide 100Hz: 0.03% 0.04% 1kHz: 0.03% 0.04% 6kHz: 0.05% 0.06% 15kHz: 0.04% 0.4% 50 Hz to 10 kHz : 0.08% 0.12% Narrow 100Hz: 0.04% 0.3% 1kHz: 0.15% 0.3% 6kHz: 0.3% 0.3% 15kHz: 0.07% 1.0% 50 Hz to 10 kHz : 0.3% 0.6%
Signal-to-noise ratio (100% modulation, 1 mv input)	mono:90dB stereo:85dB
Image interference ratio (84 MHz)	90dB
Selectivity (IHF)	wide:45dB narrow:65dB(300kHz)
IF Interference Ratio (84 MHz)	110dB
Spurious interference ratio (84 MHz)	120dB
AM suppression ratio	70dB
Capture ratio	wide:0.8dB narrow:2.0dB
Subcarrier suppression ratio	73dB
Stereo separation	wide 1kHz: 60dB 50 Hz to 10 kHz : 47dB 15kHz: 40dB narrow 1kHz: 50dB 50 Hz to 10 kHz : 35dB
Frequency characteristic	15 Hz to 15 kHz ± 0.5 dB
<AM Tuner Section>
Receiving frequency range	520 kHz to 1650 kHz
Sensitivity	10 μ V (IHF) 200 μ V/m (loop antenna)
Distortion Factor (1000 kHz)	0.2%
Signal-to-noise ratio (30% modulation, 1 mv input)	52dB
Image interference ratio (1000 kHz)	70dB
Selectivity (IHF)	wide:30dB narrow:50dB
<Output Level / Impedance>
FM (1 kHz, 100% modulation)	Fixed : 0.75V/2.2k Ω Variable : 1.5V/2.2k Ω
AM (400 Hz, 30% modulation)	Fixed : 0.25V/2.2k Ω Variable : 0.5V/2.2k Ω
<General>
Power supply voltage	100 VAC, 50Hz/60Hz
Rated power consumption (Electrical Appliance and Material Control Law)	20W
External dimensions	Width 440x Height 123x Depth 388 mm
Weight	6.5kg