Audio Database

The

ROTEL RT-2000
60,000yen( at the 1970 in-the-late time(?))

Description
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The FM/AM tuner which adopted the Quartz nowait-lock scheme.

The Quartz nowait-lock scheme by a crystal oscillator is adopted.
The Quartz nowait-lock scheme is always comparing exact 10.7MHz generated from a crystal oscillator, and 10.7MHz of a middle cycle amplification (IF). When a difference occurs here, the difference signal of plus or minus is made by a phase comparator, and the local oscillator is controlled through a low pass filter. In order that Quartz may not receive influence in a transition of humidity or a temperature, either, a frequency of oscillation remains locked and the drift after a syntony is eliminated.

Moreover, the touch nowait-lock-off scheme is adopted, while touching the tuning knob, a nowait lock is canceled, and the Quartz nowait lock works at the moment of lifting a hand.

The frequency linear-line type precision 5-unit variable condenser is adopted as a front end part. Moreover, the one dual gate MOS FET is used in RT-2000.

The IF section can switch two steps of bandwidth, and the requirement setups according to receiving requirements is possible for it.
A high selectivity property is acquired by choosing NARROW, when a radio-wave status is bad.

The carrier cancellar circuitry which omits a pilot signal (19kHz) is carried in the MPX section. Moreover, by adoption of LC block filter and PLL IC which paid attention to the damping of the subcarrier signal (38kHz), the high region fall was suppressed and a wide range is secured.

The multipath detection functionality is carried.
The pointer of a tuning meter displays in RT-2000.

The high blend switchpoint which demonstrates power is carried in the reception of a weak-electric-current community.

The 16 pin dual in-line IC puck circuitry is adopted as AM tuner part.


Rating of a mode
Form FM/AM tuner
<FM tuner part>
Sensitivity (IHF) mono: 9.8 dBf/1.7 microvolts (S/N 26dB)
stereo: 36 dBf/35 microvolts (S/N 50dB)
S/N ratio (IHF) mono:80dB
stereo:75dB
THD
mono wide:0.05%
narrow:0.15%
stereo wide:0.07%
narrow:0.2%
Capture ratio 1dB
effective selectivity (IHF) narrow:80dB
Frequency characteristic 30Hz-15kHz}0.2dB
Stereo separation 45dB(1kHz)
Image stonewalling ratio 100dB
IF stonewalling ratio 100dB
AM supression ratio 60dB
Muting 5 microvolts
<AM tuner part>
Sensitivity (IHF) 200microvolts/m
S/N ratio 55dB
Image stonewalling ratio 50dB
Selectivity 40dB
<Synthesis>
Dimensions Width 482x height 143x depth of 328mm
Weight 7.5kg