Sony ST-5090
A solid-state FM/AM stereo tuner from Sony with high sensitivity and dual output options, finished in Lawrence Oak.
Overview
The Sony ST-5090 is an FM/AM stereo tuner manufactured by Sony, designed for high-fidelity audio systems. It offers improved cost performance over the earlier ST 5070 model. The unit features a large backlit tuning meter, front-panel output level control, and a high blend switch for adjusting stereo imaging. Finished in Lawrence Oak, it was built to match other components in Sony’s audio lineup of the mid-1970s.
Specifications
| Model Rating Type | FM/AM Tuner |
| FM Tuner Section Antenna terminal | 300 Ω Balanced Type, 75 Ω Unbalanced Type |
| FM Practical sensitivity | 2.2 μ V (IHF standard) |
| FM Sensitivity | 1.7 μ V (SN ratio = 30 dB) |
| FM Signal-to-noise ratio | 68dB |
| FM Capture ratio | 1.5dB |
| FM Selectivity | 55dB(IHF) |
| FM Image interference ratio | 45dB |
| FM IF interference ratio | 95dB |
| FM Spurious interference ratio | 75dB |
| FM AM suppression ratio | 45dB(IHF) |
| FM Frequency characteristic | 30 Hz to 15 kHz +1, -3dB |
| FM Distortion factor Mono | 0.5% at 400 Hz with 100% modulation |
| FM Distortion factor Stereo | 0.8% at 400 Hz with Main 45%, Sub 45%, Pilot 10% modulation |
| FM stereo separation | 35 dB or More (400 Hz) |
| FM Output Voltage / Impedance Normal Output | 750mV / 4.5k Ω |
| FM Output Voltage / Impedance High output | 1.5V / 3.3k Ω |
| AM Tuner Section Antenna | Ferrite bar antenna, With External Antenna Terminal |
| AM Sensitivity | 48dB/m (when bar antenna is used), 100 μ V (when external antenna is used) |
| AM Signal-to-noise ratio | 50dB |
| AM Image interference ratio | 45dB(1,000kHz) |
| AM Distortion factor | 0.6% |
| Power | 100 VAC, 50Hz/60Hz |
| Power consumption | 18W |
| External dimensions | Width 416 x Height 120 x Depth 284 mm |
| Weight | 4.8kg |
Design
The ST-5090 uses a JFET in the high-frequency amplifier circuit and an FET in the mixer circuit. The IF section incorporates two solid-state filters in a single package. A sealed coil unit in the MPX circuit improves stereo separation and reduces aging effects. The FM tuner uses a frequency linear type varicon, while the AM section employs a triple-tune IFT for enhanced selectivity and low distortion. The unit includes a backlit tuning meter, front-mounted output level control, two sets of output jacks (Normal and High), and a high blend switch. It features a Lawrence Oak wood finish.
Context
The Sony ST-5090 was positioned as offering higher cost performance than the ST 5070.
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.