SONY ST-5300
¥ 39,800 (around 1969)
Commentary
An FM/AM tuner that not only has high sensitivity but also pursues sound quality in order to respond to the era of multiple FM stations.
It uses the direct FET mixer method made possible by the newly developed low-noise FET.
Without using any active elements such as transistors that cause cross-modulation in the high-frequency region, three tuning circuits using a precision four link varicon directly feed radio waves into the FET mixer to improve sensitivity, interference rejection characteristics, and strong electric field characteristics.
A newly developed 6-element solid-state filter is used in the IF stage, enabling stable reception of weak radio waves immediately adjacent to strong radio waves.
In addition, as it is a completely non-adjustable type, there is no secular change, and no long-term tuning deviation occurs.
Equipped with an automatic high blend circuit, when the radio wave is weak and the S/N of the stereo broadcast transmission is insufficient, the high blend circuit automatically operates to make it easier to hear.
It also has a reset button.
In addition to the input meter, which shows the strength of radio waves, the center 0 meter, which can be accurately tuned, is used.
A five stage limiter circuit, including a three stage symmetrical diode limiter, is robust against pulsed noise and improves the capture ratio.
A low-pass filter prevents beat interference to the tape recorder.
FET and solid-state filter are also used for the AM part, and the sensitivity and S/N are improved without distortion even in a strong electric field of 1 V.
A muting circuit using FET is adopted.
Uses a large dial with green edge light illumination.
There are two types of output terminals, fixed and variable.
.JPG)
Model Rating
| Type | FM/AM Tuner |
| Circuit system | Superheterodyne system |
| FM Tuner Section | |
| Antenna terminal | 300 Ω Balanced Type 75 Ω Unbalanced Type |
| Receiving frequency | 76 MHz to 90 MHz |
| Intermediate frequency | 10.7MHz |
| Practical sensitivity | 2.0 μ V (IHF) |
| Sensitivity | 1.6 μ V (S/N 30 db) 1.3 μ V (S/N 20 dB) |
| Signal-to-noise ratio | 70dB |
| Capture ratio | 1.8dB |
| Selectivity | 70dB(IHF) |
| Image interference ratio | 75dB |
| IF interference ratio | 90dB |
| Spurious interference ratio | 100dB |
| AM suppression ratio | 50dB(IHF) |
| Frequency characteristic | 30 Hz to 15 kHz, ± 1.0 dB |
| Distortion factor | Mono : 0.3% at 400 Hz, 100% modulation Stereo : 0.5% at 400 Hz, 100% modulation |
| FM stereo separation | 38 dB or More (400 Hz) |
| 19 khz and 38 khz suppression ratio | 60dB |
| Output Voltage / Impedance | Fixed output : 750mV/10k Ω Variable output : 0 V ~ 2V/1k Ω (at maximum output) |
| <AM Tuner Section> | |
| Antenna | Ferrite bar antenna With External Antenna Terminal |
| Receiving frequency | 530 kHz to 1,605 kHz |
| Intermediate frequency | 455kHz |
| Sensitivity | 48dB/m (when bar antenna is used) 20 μ V (when external antenna is used) |
| Signal-to-noise ratio | 46 dB at 5 mV input |
| Image interference ratio | 60dB(1MHz) |
| IF interference ratio | 46dB(1MHz) |
| Distortion factor | 0.8% (at 5 mv input) |
| <General> | |
| Semiconductor used | Transistor : 22 pcs (16 receiving circuits, 6 attached circuits) FET : 6 pcs (3 receiving circuits, 3 attached circuits) Diode : 29 units |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 13W |
| External dimensions | Width 422x Height 148x Depth 340 mm |
| Weight | 7.2kg |
| Attachment | One fader antenna for FM Connection code RK-74x1 Polishing Cloth x1 |