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





Mitsubishi M-F01 tuner


A miniature FM Stereo tuner with Mighty performance and Quartz-PLL synthesizer tuning.
The M-F01 FM stereo tuner not only guarantees absolutely free from tuning drift thereafter. Unlike conventional FM tuners, whose performance depends very largely upon how well they are tuned system ensures  that it can always without exception, give its very best performance.
The quartz PLL tuning system is the secret of how this exceptional performance is obtained. The quartz crystal gives an extremely accurate  64 MHz signal that is divided by 128 to give a basic 50 kHz frequency. Comparing this reference frequency with one-half the local oscilator frequency enables any phase difference between them to be eliminated, effectively locking them together, this circuit is the phase locked loop (PLL). Under its action, the local oscillator is limited to frequencies that are exactly 100 kHz apart - e.g. 98,7; 98,8; 98,9 MHz etc.
The total harmonic distortion is completely independent of detuning frequency over wide limits, unlike conventional tuners.
Like other members of the Microcomponent series, the M-F01 features unusually clear LED type indicators. Here the locktune indicator is linked with the dial illumination; normally the dial numbers are edge litin white , but as soon as a station is tuned and locked, this is replaced by a gentle green glow. The five Leds on the left indicate signal strength. The pointer lights on either side of the tuning lock indicator go on to show which way the tuning knob should be turned for perfect tuning. As soon as only the tuning lock LED is lit, tuning has been completed, and the stereo LED will go on if the fM station is broadcasting in stereo. Of course you can switch over to mono listening if the station is too far away for good stereo reception - although the M-F01 is so sensitive that this shouldn't happen too often.
Another useful control lets you mute out interstation noise and stations too weak for good reception, so that you only receive stations capable of top-quality reception.

Wide, Flat Frequency response
Most FM tuners have a filter to get rid of the unwanted pilot signal (at 19 kHz), but these also affect the musical signal with frequencies below 19 kHz. In the M-F01 the pilot signal is cancelled out completely without the use of a filter, so that frequency response is flat to within ±1db at 16 kHz.
High performance Front-end
The all-important front end , that captures and processes the signal uses the same high precision five ganged tuning condeser as the prestigious DA-F20. mitsubishi's top tuner, making for great accuracy and stability. The M-F01 rejects spurious signals very effectively thanks to dual gate MOS-FeT's in the RF amplifier and mixer stages, and utilizes four pole linear phase LC filters for low distortion. Outstanding temperature and humidity stability are ensured by the use of aluminium cored coils and teflon trimmer-capacitors in the local oscillator, and glass epoxy printed circuit boards, all representative of the state-of-the-art..
Recording level Check Signal
A test signal at 440 Hz corresponding to 50% modulation of the FM signal is provided for easy level setting when tape recording FM broadcasts.
Specifications
Usable Sensitivity:
Mono :  11,2 dBf (2,0 µV)
Stereo :  22,7 dBf (7,5 µV)
50 dB Quieting Sensitivity:
Mono :  19,2 dBf (5,0 µV)
Stereo :  39,2 dBf (50 µV)
Signal-to-Noise Ratio:
Mono :  80 dB
Stereo :  77 dB
Frequency Response: 30 - 16,000 Hz ±1 dB
Total Harmonic Distortion:
Mono :  0,08%
Stereo :  0,1%
Capture Ratio:  1,0 dB
Alternate Channel Selectivity:  70 dB
Image Response Ratio:  100 dB
IF Response Ratio:  100 dB
Spurious Response ratio:  100 dB
AM Suppression:  65 dB
Stereo Separation:
At 1 kHz :  50 dB
At 10 kHz :  40 dB
Subcarrier Product Ratio:  80 dB
Output Level/Impednce
Fixed :  150 mV/5 k  Ω
Variable ;  0 -500 mV/5 k Ω
Power Consumption:  10 W
Dimensions (W x H x D):  270 x 70 x 247 mm (10-5/8" x 2-3/4" x 9-3/4")
Weight:  3,5 kg (7 lb 11 oz)

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