|98,000 ( at the 1970 in-the-late time(?))
FM stereo tuner which adopted the Quartz nowait-lock
The Quartz nowait-lock scheme by a crystal oscillator is
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 tuning scheme by a LED indicator is
If a tuning knob is touched, the induced voltage will be detected
and the Quartz nowait lock will be canceled. At this time, a local frequency
changes linearly, and if it comes until the radio wave of choice has a near dial
pointer (}100kHz), the indicator of a sub- will light up. Furthermore, if a
pointer approaches the radio wave of choice, central green light emitting diode
will light up, and having aligned completely is shown. If a hand is lifted at
this time, it is shown that light emitting diode of Quartz locking-in Decatur
shone with green, and changed into the status of a nowait lock.
frequency linear-line type precision 5-unit variable condenser is adopted as a
front end part.
Moreover, in RT-2100, the three dual gates MOS FET are used
and a high sensitivity and stonewalling exclusion capacity to have excelled are
The IF section can switch two steps of bandwidth, and the
requirement setups according to receiving requirements is possible for it.
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 tape-deck level checking functionality is carried.
If a REC
CHECK switchpoint is turned on, 400Hz dial tone will come out. At the time of an
air check, this signal is set as criteria (0dB) for the level of the deck.
The multipath detection functionality is carried.
In RT-2100, the
degree of a multipath is displayed with a signal indicator.
blend switchpoint which demonstrates power is carried in the reception of a
||FM stereo tuner
||mono: 9.3 dBf/1.6 microvolts (S/N 26dB)
stereo: 36 dBf/35 microvolts (S/N 50dB)
|S/N ratio (IHF)
|Effective selectivity (IHF)
|Image stonewalling ratio
|IF stonewalling ratio
|AM supression ratio
||Width 482x height 143x depth of 328mm