LUXMAN T-50A
¥ 69,000 (released in October 1979)
Commentary
An AM/FM stereo tuner that thoroughly pursues the basic performance of a tuner and incorporates a tuning circuit to maximize the performance.
The CLL-type tuning system (Closed Loop Locked System) is adopted.
This is a tuning system that locks the front end, IF stage (intermediate frequency amplification stage), and detection stage to the transmission frequency of the FM station, ensuring stable reception performance.
The CLL circuit also has a built-in re-lock circuit (Dynamic Kick System) so that you don't have to re-tune the tuner when you turn off the power.
To achieve more accurate tuning, it is equipped with an Accu-Touch mechanism.
The control voltage of the CLL circuit is used to detect an accurate center point and to mechanically lock the tuning knob. When the tuning knob is turned at the normal speed, the knob is temporarily locked (for approximately one second) as well as the response.
The front end uses a MOS FET for the RF stage (high-frequency amplification stage), and by adopting a low-distortion local oscillator circuit, excellent interference rejection characteristics and current modulation characteristics are obtained.
In addition, the IF stage is equipped with a two stage switching of bandwidth to achieve both low distortion rate characteristics and high selectivity characteristics. In addition, a beat prevention circuit is added to strengthen measures against interference during narrow operation.
The detector stage uses NEW Racea ICs that provide broadband and low-distortion characteristics, and the stereo demodulation stage uses PLL ICs that provide separation characteristics.
The AM tuner section emphasizes input resistance to strong electric fields. In addition, the IF stage is equipped with a ceramic filter with high selectivity.
It is equipped with an FM muting level control which can freely set the electric field strength applied to muting, a signal strength indicator which displays the signal strength in 5 stages, and a center indicator which displays whether the FM station is accurately captured.
Model Rating
Type | AM/FM stereo tuner |
FM Tuner Section | |
Practical sensitivity of IHF | 1.8 μ V/10.3 dBf |
50 dB quieting sensitivity | 3.3 μ V/15.6 dBf |
Signal-to-noise ratio | 75dB |
Frequency characteristic | 30 Hz to 15 kHz ± 0.5 dB |
Distortion factor (wide, 1 kHz) | mono:0.07% stereo:0.1% |
Capture ratio | wide:0.9dB narrow:1.8dB |
2 signal selectivity (± 400 kHz) | wide:40dB narrow:80dB |
Spurious characteristic | 80dB |
Image ratio | 55dB |
Amplitude modulation suppression | 60dB |
Stereo Separation (wide) | 100Hz:45dB 1kHz:50dB |
Muting threshold | 10 μ V ~ 300 μ V |
<AM Tuner Section> | |
Practical sensitivity of IHF | 250 μ V/m |
Image ratio | 50dB |
IF interference rejection ratio | 40dB |
Signal-to-noise ratio | 50dB |
Distortion factor | 0.6% |
<General> | |
Output voltage | FM : 1V/100 Ω AM:0.3V |
Accessory circuit | CLL circuit Tuning lock mechanism IF bandwidth switching Center indicator FM muting switch FM muting level control |
Power supply voltage | 100 VAC, 50Hz/60Hz |
Power consumption | 8W |
External dimensions | Width 466x Height 120x Depth 350 mm |
Weight | 7kg |