Audio Database

The

DIATONE DA-F630
47,000yen(around the 1979 time)

Description
 
It is a FM/AM tuner in which pre-set of eight FM/AM in all is possible.

The Quartz synthesizer system is adopted. By this system, electronic tuning is enabled by changing the capacity of the amount diode of good changes using PLL and a microcomputer. In order to determine received frequency based on the standard frequency (FM0.1MHz, AM1kHz) obtained from a crystal oscillator, there are no worries about alignment gap.

By storing frequency in a microcomputer, pre-set up to eight games is possible in all.
Since the power source of a memory is a capacitor backup system, even if a power switch is turned off, the memory circuit is operating. Moreover, even if a power source is shut off to a power failure, absence recording, etc., the preset state is maintained for about 48 hours.
A setup of pre-set pushes a memory button, while receiving the broadcasting station of hope first. Then, while the memory indicator is on, it can set up by pushing the preset button of hope.

The manual tuning by a UP/DOWN button is possible.
Whenever it pushes each button once, as for FM, 0.1MHz changes and, as for AM, received frequency changes at a 1kHz step. Moreover, fast forward tuning is also possible by continuing pushing a button.

The new Quadrature wave detector which put the phase coil and the detection transformer into the same case is adopted as FM detection circuit.
Furthermore, PLL IC is adopted as a MPX circuit and a low distortion and high separation-ization are attained.

The digital display of the frequency is carried out by LED.


Rating of a mode
Form FM/AM tuner
<FM tuner part>
Practical speed 1.9 microvolts (10.8dBf)
The degree of effective selection 60dB
Capture ratio 1.5dB
S/N ratio stereo:72dB
mono:75dB
Image disturbance ratio 60dB
IF disturbance ratio 80dB
Spurious disturbance ratio 80dB
THD (1kHz) stereo:0.3%
mono:0.2%
Stereo separation 40dB(1kHz)
Frequency response 30Hz-15kHz±3dB
<AM tuner part>
Practical speed 300microvolts/m
S/N ratio 50dB
The degree of effective selection 25dB
Image disturbance ratio 40dB
THD 1.0%
<Synthesis>
Dimensions Width 424x height 140x depth of 236mm
Weight 3.4kg