TRIO ST-777T
¥ 139,000 (around 1966)
Commentary
This is the first stereo component in Japan that employs an all-transistor amplifier using a mesa-type silicon transistor.
Receiver section
The amplifier uses an OTL-ITL system with an all-transistor configuration.
It is equipped with a protective circuit and takes all possible measures.
The FM tuner is equipped with a pure electronic FM mono-stereo automatic switching system developed by Trio.
In addition, a 3-row varicon is used for the FM front-end part, and a luxurious design of 5-stage IFT is adopted.
Player part
The player has a tri-auto-start, auto-stop, and full-stop mechanism to fully automate the three operations from the start to the end of the performance.
The turntable uses an aluminum die cast with a diameter of 30 cm, and the drive motor uses a 4-pole synchronous motor that does not require fine speed adjustment.
The tone arm uses a pipe arm that reads needle pressure directly, and the cartridge is equipped with a MM type cartridge.
Speaker part
3-way 3-speaker configuration.
A 25 cm cone woofer with a strong magnet is mounted in the low range, and a 16 cm cone scoker is mounted in the middle range.
A horn type tweeter is installed in the high-frequency range.
A 12dB/oct LC-type network is used for the network section.
The enclosure is hermetically sealed.
Model Rating
| Type | Stereo component | |
| Receiver Section | ||
| Tuner Section | ||
| Receiving frequency | FM | 76 MHz to 90 MHz |
| AM | 535 kHz to 1,605 kHz | |
| Sensitivity | FM | 2.5 μ V (30% modulation, S/N20dB) |
| AM | 6.0 μ V (30% modulation, S/N10dB) | |
| Image ratio | FM | 50 dB or more |
| AM | 40 dB or more | |
| Frequency characteristic | FM | 20 Hz to 20 kHz ± 1 dB |
| Signal-to-noise ratio | FM | 70 dB or more (100% modulation, 1 mV input) |
| Distortion factor | Not more than 1% | |
| Separation | 35 dB or More (400 Hz) | |
| Amplifier Unit | ||
| Output | 26W (13W + 13W, Music Power, 1% distortion) | |
| Frequency characteristic | 20 Hz to 30 kHz ± 1 dB | |
| Input sensitivity | MAG:1.5mV Tape Play:100mV |
|
| SN ratio (maximum volume adjustment, flat tone control) | MAG : 60 dB or more Tape play : 72 dB or more |
|
| Residual noise | 2mV | |
| Entire Receiver Section | ||
| Accessory function | FM mono-stereo automatic switching device SCA Filters Tape monitor Headphone jack MPX Noise Filter |
|
| Semiconductors used | Transistor : 38 Diode : 27 units |
|
| Pwer | 100 VAC, 50Hz/60Hz | |
| Power consumption | 45VA | |
| <Player Part> | ||
| Model Name | ST-777TP | |
| Cartridge Section | ||
| Cartridge | MM Type | |
| Output voltage | 5 mv (1 khz, 5cm/sec) | |
| Needle tip | 0.7 mil diamond needle | |
| Frequency characteristic | 20 Hz to 21 kHz ± 2 dB | |
| Separation | 25 dB or More (1 kHz) | |
| Output voltage difference | Within ± 1 dB | |
| Needle pressure | 2 ~ 4g | |
| <Turntable portion> | ||
| Drive motor | 4-pole synchronous motor | |
| Turntable | 30 cm Aluminum Die Cast | |
| Number of revolutions | 3 Speed | |
| Wow | Not more than 0.2% | |
| Tone Arm Section | ||
| Format | Static balanced type pipe arm Needle pressure direct reading type 4-terminal plug-in type |
|
| Speaker Unit | ||
| Model Name | ST-777TS | |
| Method | 3-Way, 3-Speaker, Airtight System, Floor Type | |
| Units Used | For low band : 25 cm cone type For Medium Range : 16 cm cone type For High Frequency : Horn Type |
|
| Frequency characteristic | 45 Hz to 19 kHz | |
| Max Input | 15W | |
| Impedance | 8 Ω | |
| Crossover frequency | 800 Hz, 5 kHz (12dB/oct.) | |
| <General> | ||
| External dimensions | Width 1,740x Height 700x Depth 445 mm | |
| Weight | 80kg | |