TRIO KT-4005
¥ 37,500 (around 1972)
Commentary
The FM/AM tuner incorporates an independently developed double-switching and de-modulator system to improve sound quality.
In the double switching de-modulator method, the outputs of the main switching circuit and the auxiliary switching circuit are symmetrical and opposite in phase, and the leakage signal is canceled by adding the outputs of both switching circuits. A phase correction circuit is mounted in front of the auxiliary switching circuit so that the phases of the main signal and the leakage signal match.
This prevents the deterioration of the separation caused by the phase difference between the main signal and the auxiliary signal at the IF stage.
A frequency linear type varicon with linearly variable capacity is adopted, and a scale that is easy to select channels is realized by adopting an equally spaced scale.
It uses an LC-type filter developed by a unique method, and achieves a carrier suppression almost equal to the SN ratio.
It also prevents beats from occurring when recording with a tape recorder with low oscillation bias and large leakage.
The tuner coil is resistant to temperature and humidity by adjusting the structure and winding method, adjusting the compounding agent of the core, and matching the temperature characteristics of the phenol resin covering the core and core.
.JPG)
Model Rating
| Type | FM/AM Tuner |
| FM Tuner Section | |
| Receiving frequency | 76 MHz to 90 MHz |
| Antenna impedance | 300 Ω equilibrium 75 Ω unbalance |
| Sensitivity | 1.9 μ V/84MHz |
| Chinese arrowhead's slope | 48 dB (3 μ V) 60 dB (10 μ V) 70 dB (50 μ V) |
| Distortion factor | 0.4% |
| SN ratio (100% modulation, 100 μ V input) | 70dB |
| Capture ratio | 2.0dB |
| Selectivity (IHF) | 60dB |
| Image ratio | 55dB(84MHz) |
| IF interference ratio | 90dB(84MHz) |
| AM suppression ratio | 55dB |
| Harmonic spurious response | 90dB |
| Multipath output | 0.15 V (both vertical and horizontal) |
| Multipath impedance | 20k Ω |
| <FM MPX Part> | |
| Separation | 40dB(400Hz) 35 dB (100 Hz to 8 kHz) |
| Carrier leakage | -60dB |
| Distortion factor | 0.7% |
| Signal-to-noise ratio | 65dB |
| Frequency characteristic | 50 Hz to 15 kHz + 0. 2-0. 5 dB 100 Hz to 10 kHz + 0.2 -1.5 dB |
| SCA interference ratio | 60dB |
| <AM Tuner Section> | |
| Receiving frequency | 520 kHz to 1610 kHz |
| Sensitivity | 18 μ V (IHF) 300 μ V/m (bar antenna) |
| Image ratio | 50dB |
| IF interference ratio | 40dB |
| Signal-to-noise ratio | 50dB |
| Selectivity | 30dB |
| Distortion factor | 1% |
| <General> | |
| Rated Output (400 Hz) | FM (100% modulation) : 1.5 V AM (30% modulation) : 0.15 V |
| Output impedance | 12.5k Ω |
| Power supply voltage | 100 VAC / 117 V, 50Hz/60Hz |
| Rated power consumption (Electrical Appliance and Material Control Law) | 15W |
| External dimensions | Width 435x Height 153x Depth 300 mm |
| Weight | 8.1kg |