Marantz Model125
¥ 84,900 (released in 1975)
Commentary
An FM/AM tuner developed with the most advanced technology and materials at present.
The front end is fed from an RF-amplifier using a dual-gate MOS-FET through a 3-stage tuning Butterworth type RF-tank circuit and then to the mixer stage of the dual-gate MOS-FET. A unique direct connection method is adopted between the front end and the mixer stage to cope with adverse effects of PC board and solder flux and to improve performance.
In addition, in the mixer stage, we pay attention to the thermal and electrical characteristics of the local oscillator and minimize the drift (mistuning) to eliminate the AFC circuit which causes the sound quality degradation.
The IF stage is equipped with a newly developed ultra-high performance LC type linear phase IF filter.
This filter consists of one 6-pole filter and three 4-pole filters. The phase of the filter is linear within the 200 kHz band path centered at 10.7 MHz, and it has sharp cutoff characteristics. This allows the phase linearity to eliminate distortion in the high-frequency range and prevents degradation of stereo separation.
The MPX circuit uses an integrated PLL circuit.
Since this system automatically locks the phase of the subcarrier oscillator to the pilot signal of the broadcasting station, stability is higher than that of conventional coil and condenser systems, and low distortion and high separation are realized.
Equipped with an output level control knob.
The wood cabinet in the picture was sold as an option to be sold separately and there were 2 types, mahogany and walnut.
Also, there was an optional rack mount adapter sold separately.
Model Rating
| Type | FM/AM Tuner |
| FM Tuner Section | |
| Tuning frequency range | 76 MHz to 90 MHz |
| Sensitivity (30 dB Quadrature) | 1.4 μ V |
| Selectivity (IHF) | 80dB |
| Capture ratio | 1.0dB |
| Image rejection ratio | 100dB |
| Signal-to-noise ratio | mono:70dB stereo:60dB |
| Distortion factor | mono:0.15% stereo:0.3% |
| Frequency response (50 μ sec, de-emphasis) | 30 Hz to 15 kHz ± 1 dB |
| Stereo separation | 42dB(1kHz) 30dB(10kHz) 36dB(200Hz) |
| <AM Tuner Section> | |
| Tuning frequency range | 535 kHz to 1,605 kHz |
| Sensitivity | 20 μ V |
| Selectivity | 30dB |
| Image interference ratio (1,400 kHz) | 70dB |
| Signal-to-noise ratio | 50dB |
| Frequency response (-3dB down) | 50 Hz to 4 kHz |
| Distortion factor | 1% |
| <General> | |
| Pwer | 100 VAC, 50Hz/60Hz |
| Power consumption | 25W |
| External dimensions | Width 390x Height 146x Depth 300 mm (Width and height are panel dimensions) |
| Weight | 8kg |
| Sold Separately | Mahogany Cabinet WC-1AN (¥ 12,000) Walnut Cabinet WC-3 (¥ 5,900) Rack Mount Adapter RA-2 (¥ 5,900) |