Leak stereofetic fm tuner owners manual

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LEAK

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Advanced design techniques to get the best
from an F.M. signal

The frequency modulated (FM) Signals transmitted
by the major broadcasting organisations are capable
of producing very high quality speech and music
when fed into Hi-Fi amplifier systems.

The Stereofetic FM Tuner has been carefully
desrgned to add the minimum of horse and
distortion on to the high quality broadcast srgnal,
unlike many F.MV tuners which do not allow these
srgnals to realise their full potential,

The Stereofetic uses the latest components and
Circuit techniques in order to achieve these ends:

Field effect transrstors (FtET's) in the input stages
to reduce overload distortion and norse;
Integrated circuits (| CS) in both the IF strip and
decoder to Increase the rejection of ignition

Interference and to improve the separation
between right and left audio channels;

0 Ceramic filters in the |.F. stages to improve the
selectrvrty and reduce the distortion of stereo
Signals;

o A specral peak reading tuning indicator to help the

operator tune to absolute minimum distortion;

0 A specral doubleeaction muting crrcuit to
eliminate inter-station horse and reduce the
in-and-outtuning 'plops';

o A special designed wide band ratio detector to

reduce distortion and noise on the detected audio

Signal;

0 Three 19 kHz and two 38 kHz band stop filters to

eliminate whistles when usrng the tuner in
conjunction with a tape recorder;

c A new desrgn philosophy (which we have called
quasi-stereo) to reduce the background norse on

distant stereo programmes wrthout losrng the
stereo effect.

In addition to these special features the Stereofetic

F.M. Tuner has eliminated the irritation of the
multi-position mains voltage selector by usrng a
simple two-position plug-it is set either to
100-130 volts or to 200-250 volts. arc.

Operating the Stereofetic FM Tuner
The Stereofetic F.M. Tuner has been designed as a
dual-purpose instrument:

1 i

For 'casual listening' to local stations during the
daytime chores. When tuning the Stereofetic to
local stations for background music the
right-hand three push-buttons should be
pushed in. (See illustration below)

Only those broadcasts with a received signal
strength above 12 microvolts will now be heard.
and the automatic frequency control (A.F.C.)
will ensure that the tuner locks in to station as
soon as the aerial signal exceeds that level.

For the Hi-Fi enthusiast who wants minimum
distortion, low noise and long distance reception.
With no mute or A.F.C. buttons operated, input
signals as low as 2% microvolts will produce a
reasonably noise-free and low-distortion output

signal.

The Tuning Indicator
The tuning indicator acts as both a tuning meter and
as a stereo beacon. When mono signals are being
received, or when the Mono Lock' button is
pushed in, the pointer will stay in the black region
(figures 1 and 2). When stereo signals are being
received, the pointer will be in the red region
(figures 3 and 4).

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- - STEREO
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1.

'Casual listening' tuning.

Distortion less than 1%
at average modulation
levels,

2. 'Hi-Fi' tuningt

Distortion less than
25% at average
modulation.

"3"

my

Stereo casual' tunings
Distortion less than 1%
at average modulation
levels. Separation
better than 24 dB at

1 kHz

'Hi-Fi' stereo tuning.
Distortion less than
.2596 at average
modulation levels
Separation better than
30 dB at 1 kHz