SONY ST-JX4
¥ 39,800 (around 1981)
Commentary
FM/AM tuner equipped with an FM/AM direct random 8-station preset mechanism.
Up to eight FM/AM stations can be preset at random. In addition, a multi-process memory is used to simultaneously store the FM mode and the SENS switch ON/OFF setting for AM for each station.
It is equipped with a SENS switch that improves the actual sensitivity of AM. This function is effective in AM broadcasting when receiving a distant station with a lot of noise or when beat interference caused by strong radio waves from overseas. When the switch is turned ON (when DISTANT is displayed), the effective sensitivity can be improved by approximately 40% due to the effect of the active filter that cuts not only the high band but also the low band.
It uses non-volatile memory that does not require a backup power supply, and can be used for recording messages on weekly timer etc.
It also has a Last Station Memory that stores the last station received when the power switch is turned off.
Quartz lock digital synthesizer system is adopted.
A 4-stage varicap and a dual-gate MOS-FET are used for the front end.
It is equipped with CAL TONE.
Equipped with a 100 kHz beat cut filter.
Equipped with a fluorescent indicator.
Model Rating
| Type | FM/AM Tuner |
| Practical sensitivity | 1.8 μ V (IHF), 10.3 dBf (new IHF) |
| Stereo distortion factor | 0.08% |
| Effective selectivity | 85dB |
| Spurious interference ratio | 100dB |
| Separation | 50dB |
| Power consumption | 10W |
| External dimensions | Width 430x Height 55x Depth 330 mm |
| Weight | 3.6kg |
| Attachment | Station name display card |