Audio Database

The

Accuphase T-109
150,000 yen(December, 1993 release)

Description
 
FM stereo tuner which aimed at the ultimate grade as a tuner for the music fan who asks for the highest sound quality.

The alignment for tuning can align with the office of choice with high precision with a crystal oscillator, most gaps by time or a temperature change cannot be found, and it locks at the point of the distorted minimum and sensitivity highest.
Moreover, the abnormal-conditions distortion or noise by external vibration are not made for electronic tuning.

Before amplifying in a front end in an antenna circuit, the antenna double tuning circuit which lets a selection circuit pass is adopted as it, and the intermodulation generated by amplifying directly at the time of the Dainyuu power is prevented.
FET of cascode amplifier (circuit which connected two amplifiers to cascade and improved frequency response) composition with little feedback is adopted as high frequency magnification. The Attenuator by a PIN diode is prepared in the gate of this input, this Attenuator is turned on and off with a microcomputer with an antenna input level, and the excess Dainyuu power in the area where a transmitting tower is near is coped with.
Moreover, the balanced mixer circuit by push pull FET was adopted as the mixer, generating of higher-harmonic-wave distortion was suppressed in it, and the disturbance signal is eliminated in it.

The Advanced DGL detection circuit which added an extensive improvement for the DGL (Fifferential Gain Linear) circuit which is not adjusted [ high performance, quantity reliability, and ] to the base is newly carried. In the input unit of this circuit, beat disturbance is made for there to be nothing at a 2.4MHz broadband amplifier using the high-speed comparator. Moreover, stability is raised to the delay circuit using 24 high speed C-MOS IC.
The principle of operation has the composition that the delay circuit delayed the degree of phase angle 114 degrees so that the distorted minimum and the signal to noise ratio might become the maximum by 24 ICs paying attention to the delay time of the output of a high-speed logic IC. This delay signal and incoming signal are applied to an exclusive OR circuit, the electric potential between two signals is chosen, and a circuit is opened and closed. The compression wave produced by abnormal conditions at this time was detected in digital one, and the audio signal is taken out.
This system has a linear region of a delay circuit as large as ±2.4MHz, and, moreover, the differentiation profit straight line characteristic of it having been stable and having excelled can be acquired for no adjusting.

IF stage has adopted the two-step change of Normal and Narrow.
Usually, the sharp reception focused on a selection degree is possible by using NORMAL of broadband reception, and changing to NARROW, when interference with an adjoining broadcasting station is intense.

In the stereo recovery part, the internal oscillating circuit was locked by the PLL circuit (fixation), and the exact 38kHz switching signal has been acquired.
In T-109, the system which combined the positive/negative variable reactive circuit controllable on control voltage with the ceramic resonance child is adopted as the internal oscillating circuit of this PLL. Thereby, an exact switching signal is acquired in the lock frequency range narrower than before.
In this circuit, since the lock frequency range which does not almost have change of the separation rate by adjust[ no ]-izing of a stereo recovery circuit and reservation of long-term stability, change of a temperature change and line voltage, etc. is narrow, there are the features, like there is little beat disturbance in high frequency.

If a 16-game memory is carried and the memory is carried out beforehand, it can call with a button in an instant.
Moreover, in accordance with a situation, the memory of each functions, such as Selectivity, Meter, Filter, Muting, and Mono, can be carried out according to an electric wave state.
The microcomputer of Accuphase original is used for these functions, and the clock frequency has taken the bowl clock system which carries out a divide from the PLL frequency of an electronic tuning circuit, and is suppressing beat disturbance.

Besides memory tuning, the manual alignment machine by the rotating knob of a pulse tuning system is carried.
The disc which was attached to the shaft of a rotating knob and in which the slit was cut radiately generates a pulse by passing a phase detector (non-contact [ by light ]), and this has structure which inputs this pulse into a microcomputer and controls the alignment frequency of PLL.
Rotation of a knob will tell change of frequency by generating of a beep sound.

The balance circuit is carried in the audio output, the noise ingredient of a signal cable or an earth line is eliminated, and noise-free high-quality sound transmission is possible.

The check of an antenna incoming signal level and a multipass is possible for meter by a changeover switch.
a multipass is peculiar to an FM broadcast and is generated by a multiple reflection wave (ghost) -- it is distorted. Since this can be prevented by direction of an antenna, it chooses a broadcasting station so that a multipass may become the minimum in meter, or adjusts the direction of an antenna.
The antenna incoming signal can check the intensity of an electric wave depending on how depending on which meter sways, and the signal to noise ratio becomes good, so that the deflection of a needle is large.

The muting switch which removes the noise filter which reduces the noise of the weak stereo office of an electric wave as an attached function, and the noise between offices, the mono-switch compulsorily used as a monophonic recording, and the output level control are carried.

Tuning and various functions are controllable with an attached remote commander.

Internal
Attached
Front

Rating of a mode
Form FM stereo tuner
<Monophonic characteristic>
Received frequency 76.0MHz - 90.0MHz
Practical speed 11dBf(IHF)
S/N 50dB sensitivity 17dBf(IHF)
Standing-wave ratio 1.5
S/N (80dBf input, A compensation) 90dB
THD
(at the time of 80dBf input, ±75kHz deflection, and Normal)
20Hz:0.02%
1kHz:0.02%
10kHz:0.02%
IM distortion (80dBf input, ±75kHz deflection) 0.01%
Frequency response 10Hz-16000Hz+0 -1.0 dB
The degree (IHF) of 2 signal selection
Disturbance wave Normal Narrow
400kHz 70dB 100dB or more
300kHz 30dB 100dB
200kHz 10dB 40dB
Capture ratio 1.5dB
RF inter-modulation 80dB
Spurious disturbance ratio 120dB
Image ratio 100dB
AM oppression ratio (65dBf input) 80dB
Subcarrier oppression ratio 70dB
SCA disturbance ratio 80dB
Output voltage (±75kHz deflection) 1.0V
<Stereo characteristic>
Sensitivity S/N 40dB sensitivity: 29dBf (IHF)
S/N 50dB sensitivity: 37dBf (IHF)
S/N (80dBf input, A compensation) 85dB
THD
(at the time of 80dBf input, ±75kHz deflection, and Normal)
20Hz:0.04%
1kHz:0.04%
10kHz:0.04%
IM distortion (80dBf input, ±75kHz deflection) 0.03%
Frequency response 10Hz-16000Hz+0 -1.0 dB
Stereo separation 100Hz:50dB
1kHz:50dB
10kHz:40dB
Stereo change inlet pressure 20dBf
<Synthesis>
Antenna 75-ohm disequilibrium
Alignment system Quartz synthesizer system
16-game random memory tuning
Detection system Advanced DGL system
Output load impedance
Balanced (balanced XLR type) : 200ohms (100ohm/100ohm)
Unbalanced (disequilibrium) Fixed (fixed output): 200ohms
Controlled(variable output): 1.25kohm (maximum)
Meter Signal strength, a multipass change type
Power supply voltage AC100V, 50Hz/60Hz
Power consumption 15W
The maximum Dimensions Width 475x height 140x depth of 402mm
Weight 9.5kg
Attachment: Remote commander RC-12
Remote control system Infrared pulse system
Power source DC3V
Battery SUM-3 type (IEC name R6) two-piece use
The maximum Dimensions 64mm[ in width ] x height 149x depth of 18mm
Weight 145g (battery included)