What is stereo?

There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.

H.H. Scott '59

Technics ST-8044

 The first requirement in an FM tuner that is designed to furnish high fidelity reception is accurate tuning.  If the tuning is off just a bit, there is an increase in distortion and decrease in stereo separation, two problems which can negative the virtues of even the best tuner designs.
In the ST-8044, the problem of inaccurate tuning was solved quite simply. First, Technics designers removed all needle-type mechanical meters, which are usually used to indicate signal strength  and center-of-channel tuning, and replaced them with responsive and easy-to-read LED's .  And once you've tuned in a ststion, the active servo lock will keep it from drifting despite temperature and humidity changes. In short, with the ST-8044, accurate tuning aids and the servo lock contribute directly to low distortion and stable stereo separation.
 Active Servo Lock
One way to prevent frequency drift and its accompanying distortion is to "lock" the local oscilator. But with this approach, the IF stage and FM discriminator cannot respond to temperature changes, which occur as the tuner "warms up", and other varying conditions. However, the Active Servo Lock in this tuner maintains precise, center-to-channel tuning under these conditions by preventing frequency drift not only in the local oscilator but also in the IF stage and FM discriminator. The big merit is that even a careless or hasty setting of the dial is sufficient to tune in the station accurately with the ST-8044. Where as you normally would have to  position the center-tuning meter rather carefully for low distortion and good stereo separtion. with  the active servo lock you can tune within ±75 kh on either side of the station's frequency. The active servo lock is then activated three seconds after the tuning LED's light up, and at the same time the "Servo Lock" indicator light goes on.
Just tune the ST-8044 to the general area of the station and the active servo lock will do the rest. If for any reason you want to defeat the servo lock, you can do so by pressing a switch.
 High-Sensitivity Front End
The RF stage benefits from, among other components, a junction FET for good selectivity, sensitivity, image and spurious rejection. Tuning is accomplished with a precision3-ganged variable tuning capacitor, and the figures tell the story of the high-sensitivity of this tuner; usable sensitivity is 1,9 µV (300 Ω). The more important 46 dB stereo quieting sensitivity is 2,5 µV (75 Ω).

High S/N Ratio and Wide, Stable Separation
In the IF stage, you'll find three flat-group-delay ceramic filters for high selectivity and a five-stage differential amplifier with excellent limiting characteristics. Selectivity is 75 dB; the S/N Ratio is 75 dB (IHF), and separation is a wide 45 dB at 1 kHz, MPX decoding is accomplished with a PLL (phase locked loop) circuit incorporated into a single IC.
 5 LED's Indicate Signal Strength
The number of LED's lit indicate signal strength in a linear progression. One LED means that the signal is very weak and is barely being picked up by the tuner. Two LED'ss mean that the station is weak and the program material will be difficult to hear. Three LED's ; the quality of the sound will not be very good, but speech can be readily understood and music will be listenable.  Four LED's ; the signal is strong enough for good musical fidelity. Five LED's; strong signal, bets possible reception with this tuner.
 Other Features
Quadrature detector with outstanding characteristics contributing to a wide, flat frequency  response and low distortion.
Easy-to-read 220 mm dial scale. The tuning knob's "positive" feel is enhanced by an oil-less sleeve and a dial rope coated with fluoro-resin.
Special muting circuit to reduce pop noise when detuning.
Fm Auto/Mono switch and FM muting to eliminate inter-station noise when tuning between stations.
High-quality AM section with 2-ganged variable capacitor and ceramic filter.
FM Tuner Section
Frequency range:  88 - 108 MHz
S/N 30 dB :  1,9 µV (300 Ω);  1,3 µV (75 Ω)
S/N 26 dB :  1,7 µV (300 Ω);  1,2 µV (75 Ω)
S/N 20 dB :  1,5 µV (300 Ω);  0,9 µV (75 Ω)
IHF usable Sensitivity:  1,9 µV (IHF '58)
IHF S/N 46 dB Stereo Quieting Sensitivity:  25 µV (75 Ω)
Total Harmonic Distortion (1 kHz):  0,15% (mono);  0,3% (stereo)
Signal-to-Noise Ratio:
Mono :  68 dB (75 dB, IHF)
Stereo :  65 dB (70 dB, IHF)
Frequency Response:  20 Hz - 15 kHz,  +0,5 dB -1,5 dB
Alternate Channel Selectivity:  75 dB
Capture Ratio:  1,0 dB
Image Rejection at 98 MHz:  55 dB
Spurious response Rejection at 98 MHz:  80 dB
AM Suppression:  55 dB
Stereo Separation:  45 dB at 1 kHz;  35 dB at 10 kHz
Carrier Leak:
19 kHz :  -35 dB (-40 dB, IHF)
38 kHz :  -48 dB (-40 dB, IHF)
Channel Balance:  250 Hz - 6300 Hz  ±1,5 dB
Limiting Point:  1,2 µV
IF Amplifier :  180 kHz
FM Demodulator :  1000 kHz
Antenna Terminals:  300 Ω (balanced), 75 Ω (unbalanced)
AM Tuner Section
Frequency Range:  525 - 1605 kHz
Sensitivity S/N 20 dB :  30 µV,  250 µV/m
Selectivity:  30 dB
Image Rejection at 1000 kHz:  50 dB
IF Rejection at 1000 kHz:  40 dB
Output Voltage:  0,6 V (fixed)
Power Consumption:  16 W
Power Supply:  Ac 110/120/220/240 V, 50/60 kHz
Dimensions (W x H x D):  430 x 142 x 254 mm (16-15/16" x 5-19/32" x 10")

Weight:  4,2kg (9,3 lbs)

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