Technics SA-103
¥ 49,800 (released in 1981)
Commentary
This is an FM/AM stereo tuner amplifier that combines a 20W + 20W amplifier and a tuner in a slim size.
The FM front-end is designed with high sensitivity by adopting a junction FET and a high-precision 3-row varicon in the RF stage. In addition, two ceramic filters are used in the IF stage, and low distortion and high selectivity are achieved by the all-stage differential configuration with excellent limiter characteristics.
The MPX demodulation circuit employs a double differential switching system using a PLL IC.
Equipped with a tuning monitor mechanism that lights up orange when detuning and green when tuning.
The input stage of the main amplifier consists of a differential amplifier with a current mirror load capable of selecting a low-distortion operating current, and a low-impedance emitter follower drives the pre-drive.
The complimentary service stage consists of a two stage Darlington semi-output push-pull circuit.
The equalizer circuit of the preamplifier section employs a differential 2-stage amplifier circuit that combines a discrete configuration with low-noise transistors and an IC.
It is equipped with a pure electronic protection circuit to protect the amplifier from shorting of the speaker terminals.
The tuner and preamplifier are driven at a fully constant voltage to achieve stable operation.
Equipped with 2 types of speaker terminals that can be used for 2 pairs of speakers.
Equipped with FM mode switch, 5 LED signal strength indicator and loudness switch.
Model Rating
| Type | FM/AM Receiver |
| Amplifier Unit | |
| Effective output (both channel drive) | 20W + 20W (8 Ω, 20 Hz to 20 kHz) |
| Total harmonic distortion factor | 0.04% (20 Hz to 20 kHz at Rated Output) |
| Damping factor | 30 (8 Ω) |
| Input Sensitivity / Impedance | Phono : 2.5mV/47k Ω Tuner, Aux/TV, Tape : 150mV22k Ω |
| Signal-to-noise ratio | Phono:80dB |
| Frequency characteristic | Phono : RIAA standard curve ± 0.8 dB Tuner, Aux/TV, Tape : 5 hz to 70 khz -3dB |
| Tone control | Bass : ± 10 dB (50 Hz) Treble : ± 10 dB (20 kHz) |
| Load impedance | Main or remote : 4 Ω ~ 16 Ω Main + remote : 8 Ω ~ 16 Ω |
| FM Tuner Section | |
| Receiving frequency | 76 MHz to 90 MHz |
| Practical Sensitivity (75 Ω) | 10.8 dBf (1.9 μ V, IHF' 58) |
| SN ratio 50 dB sensitivity | Stereo : 38.3 dBf (45 μ V, IHF' 58) |
| Distortion factor | mono:0.15% |
| Signal-to-noise ratio | mono:75dB |
| Frequency characteristic | 20 Hz to 15 kHz + 1-2 dB |
| Effective selectivity | 68dB |
| Capture ratio | 1.2dB |
| Image interference ratio | 50dB(83MHz) |
| IF interference ratio | 80dB(83MHz) |
| Spurious interference ratio | 80dB(83MHz) |
| AM suppression ratio | 50dB |
| Stereo separation | 45dB(1kHz) |
| Antenna terminal | 75 Ω Unbalanced Type |
| <AM Tuner Section> | |
| Receiving frequency | 525 kHz to 1605 kHz |
| Practical sensitivity | 30 μ V/m |
| Selectivity | 30dB |
| Image interference ratio | 50dB |
| IF interference ratio | 40dB |
| <General> | |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 65W |
| External dimensions | Width 430x Height 86x Depth 297 mm |
| Weight | 5.5kg |