Leak trough line 2 service manual v3

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H. Jr LEAK & CO. LTD.

TROUGH-LINE II EM. TUNER

INSTALLATION, OPERATION and MAINTENANCE

Connecting the RM. Tuner.

I, This unit may be used free-standing on a table, or it may be mounted on a panel of any thickness, through a cut-out
of 10%X 3% (27 cms. ><9~85 ems). To mount on a panel: remove the rubber feet by pulling smartly out of their
retaining holes; pass the body of the tuner through the cut-out until the front plate butts against the panel, then pass
the U-shaped bracket over the back of the tuner and fix it by passing the wing screw through the hole in the bracket
and into the threaded hand-bush in the centre of the rear panel on the tuner. Tighten the wing screw just enough to
prevent the metal backing on the front plate of the tuner from slipping on the panel.

2. The mains transformer primary is wound for voltages between 210 and 250 (50 to 60 c/s) or on the alternative model
for voltages between 110 and 124 (50 to 60 0/5). The circular voltage selector (situated at the back of the tuner)
should be withdrawn to its fullest extent, rotated to the voltage nearest to your supply and reinserted.

3. When used with a LEAK power amplifier the mains supply for the tuner can be obtained by inserting the A.C.
POWER plug into the AC. outlet socket on the power amplifier. The tuner is switched on by turning the volume
control.

4. The 300 ohm aerial input is balanced to earth. When using 300 ohm twin feeder, the conductors should be
connected to the outer aerial terminals. When using an unbalanced 70-80 ohm feeder, the inner central conductor
should be connected to either of the outside terminals and the outer screening connected to the centre chassis
terminal.

In many localities (covering perhaps 80% of the population) good reception of the BBC. transmissions will be
possible with an indoor aerial, but it should be remembered that the signal/noise ratio will always be better with an
efiicient outdoor aerial. Even with a very sensitive receiver such as this it is desirable to use an outdoor aerial
correctly orientated, the optimum position being indicated by maximum closure of the tuning indicator pattern

5. The output voltage from this tuner is approximately 1 volt. Due to the use ofa cathode follower output stage the
output impedance does not exceed 12,000 ohms. This means that up to 20 ft of low-loss co-axial screened cable

can be used to connect the tuner to its associated pre-amplifier without audible loss of high frequencies.

6 This tuner unit is earthed to its associated pre-amplifier via the screening of the AUDIO OUTPUT lead, and no
additional earth connection should be made to any part of the tuner.

REF. Iol

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Operating the RM. tuner.

7 The tuning indicator used on this FM. tuner is of the maximum closure type and only becomes operative when the
AFC is switched OFF. In order to tune in a station. it is therefore necessary to switch of? the AFC and adjust
the tuning control until a minimum gap exists between the two vertical light strips Switching the AFC ON" locks
the station in tune and removes the HT supply from the tuning indicator:

8: ln locations of very high signal strength, the sensitivity switch should be set to LOC: following this procedure
will suppress some of the unwanted inter-station noise.

Frequency Range:
Drift:

Sensitivity:

Aerial Impedance:

Audio Output:

Multiplex Output:

A.C. Power:

Valves:

Dimensions :

Weight:

SPECIFICATION
88-108 Mcst
3 kcis maximum with AFC VON".715 kc 5 maximum with AFC OFF".
2 micro-volts at the aerial terminals for full limiting
300 ohms balanced with centre tap earthed (7080 ohm unbalanced).

Cathode follower output delivers approximately 1 volt and facilitates the use of
long output leads with negligible high frequency attenuation.

For connection to a multiplex adaptor to obtain stereophonic reproduction from
stereo F.M. transmissions, when these are available.

200/250 volts, 50/60 cs 45 watts:
Alternative model 1105124 volts, 50560 cs 45 walls

2 X ECFSO, ECC84, ECC85, EF80, EM84, E280. 2 >< OA79,
I festoon lamp 6V 2 watt,

Front panel: 11%X4116" (29-2>< l [-2 cms.).

Chassis: |0%><3%"><7% (26-6><9-5>< l9-7 cms.).
Cut-out: 10§><33§ (27X9r85 ems).
I 1 lb, (Skgs.).