National/Technics SA-53
¥ 79,800 (around the late 1960 s)
Commentary
Integrated amplifier with ITL-OTL circuit.
The main amplifier uses ITL and OTL circuits with no transformer for both input and output to reduce distortion.
An all-silicon transistor configuration is adopted, and noise is reduced by using silicon transistors even for the PNP driver circuit.
It has terminals for the output of the preamp section and the input of the main amplifier section, and can be used independently.
By using an FET in the FM tuner section, high sensitivity and selectivity are obtained, and cross-modulation and spurious interference are eliminated to enable more stable reception.
In addition, 5-stage amplification and 2-stage direct-coupled limiter in the IF stage prevent external noise and Radio noises.
The FM multiplex section uses a ceramic filter with excellent moisture resistance and heat resistance to prevent malfunctions caused by inter-station noise.
By applying a forward AGC to the high-frequency stage of the AM tuner section, the disadvantage of the transistor-type AM receiver can be covered. In addition, the built-in ceramic IF filter uses its mechanical resonance to expand the receiving band and increase selectivity.
Ferrite antenna is used for the antenna.
Model Rating
| Type | Stereo integrated amplifier |
| Circuit system | Quasi complimentary service SEPP-ITL-OTL |
| Main Amplifier Section | |
| Music Power (IHF) | 30W + 30W (4 Ω) 27.5W + 27.5W (8 Ω) |
| Effective power | 20W + 20W (4 Ω) 21W + 21W (8 Ω) |
| Total harmonic distortion factor | 0.5% or Less (1 kHz at Rated Output) |
| Output bandwidth | 15 hz to 70 khz -3dB |
| Damping factor | 50 (8 Ω) |
| Frequency characteristic | 20 Hz ~ 90 kHz + 0 -3dB |
| Residual noise | 2 mv or Less (8 Ω) |
| Preamplifier Section | |
| Frequency characteristic | Aux : 30 Hz to 50 kHz ± 3 dB |
| Input Sensitivity / Impedance | Phono : 3mV/47k Ω Aux : 230mV/35k Ω Tape : 250mV/35k Ω |
| Signal-to-noise ratio | Phono : 65 dB or more Aux : 80 dB or more |
| Equalizer | (NF Type) Phono : RIAA |
| Tone control | Bass : ± 10 dB (50 Hz) Treble : ± 10 dB (10 kHz) |
| Loudness control | 100 Hz : + 7 dB, 10 kHz : + 3.8 dB |
| Input terminal | MAG, Ceramic, Aux, Tape FM antenna terminal AM antenna terminal |
| Output terminal | Headphones, Tape Speaker (2 systems) AC outlet |
| DIN connector | Route 1 |
| FM Tuner Section | |
| Receiving frequency | 76 MHz to 90 MHz |
| Sensitivity (IHF) | 1.8 μ V |
| Distortion factor | Mono : 0.5% or less (400 Hz, 100% MOD) |
| Signal-to-noise ratio | 60 dB or More (1 kHz, 100% MOD) |
| Image interference ratio | 80 dB or More (84 MHz) |
| Stereo separation | 40 dB or More (1 kHz) |
| <AM Tuner Section> | |
| Receiving frequency | 525 kHz to 1,605 kHz |
| Sensitivity (IHF) | 20 μ V |
| Signal-to-noise ratio | 60 dB or more |
| Image interference ratio | 60 dB or More (1,000 kHz) |
| Antenna | Ferrite antenna |
| <General> | |
| Semiconductor used | Transistor : 51 FET : 2 Diode : 29 units |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 120W at maximum output |
| External dimensions | Width 500x Height 129x Depth 357 mm |
| Weight | 12.5kg |