The Fisher AD-840 is a vintage HiFi CD player from the 1980s technical specifications for this model:

1. **CD Compatibility**: Supports playback of standard compact discs (CDs) including CD-DA (Compact Disc Digital Audio) and CD-R/RW discs.

2. **Digital-to-Analog Converter (DAC)**: Equipped with a high-quality DAC for converting digital audio signals from CDs to analog audio output.

3. **Playback Modes**: Offers various playback modes such as repeat, random, program, and intro scan for versatile listening experiences.

4. **Sampling Rate**: Typically supports CD audio playback with a standard sampling rate of 44.1 kHz and 16-bit resolution.

5. **Frequency Response**: Provides a wide frequency response range, typically from 20 Hz to 20 kHz, ensuring faithful reproduction of audio signals.

6. **Signal-to-Noise Ratio (SNR)**: Delivers a high signal-to-noise ratio for clear and distortion-free audio playback, commonly around 90 dB or higher.

7. **Dynamic Range**: Offers a wide dynamic range, typically exceeding 90 dB, allowing for detailed reproduction of soft and loud audio passages.

8. **Output Connectors**: Features analog audio output connectors such as RCA jacks for connecting to amplifiers, receivers, or powered speakers.

9. **Display**: Includes a fluorescent or LED display panel for showing track information, playback status, and other relevant details.

10. **Remote Control**: Comes with a remote control unit for convenient operation from a distance, enabling functions such as play, pause, stop, skip, and volume control.