Roberts R757 Technical manual

R
ROBERTS
Sound for Generations
BY APPOINTMENT TO
HER MAJESTY THE QUEEN
SUPPLIERS & MANUFACTURERS
OF RADIO AND TELEVISION
ROBERTS RADIO LIMITED
Operating Instructions
3-Band
Portable
Radio

If you need any further advice, please
call our Technical Helpline on
020 8758 0338 (Mon- ri)
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Controls (top panel)
1. Headphone socket
2. On/Off and Volume control
3. Tone control button
4. Wa eband buttons
5. Tuning control
6. Telescopic aerial
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3
AC Adaptor
Revival Range
Classic Range

If you need any further advice, please
call our Technical Helpline on
020 8758 0338 (Mon- ri)
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General
Do not allow this unit to be exposed to water, steam or sand. Do not lea e the unit
where excessi e heat could cause damage such as in a parked car where the heat
from the sun can build up e en though the outside temperature may not seem too
high. It is recommended that the FM band be used were e er possible as better
results in terms of quality and freedom from interference will usually be obtained
than on the MW or LW bands.
Mains adaptor
Plug the adaptor into a 13A mains outlet. Plug the lead from the adaptor into the
DC socket, located on the rear of Revival models and on the left hand end on
Classic models. The battery will be automatically disconnected.
The mains adaptor should be disconnected from the mains supply when not in
use.
Battery
Revival models. Open the rear door by releasing the catch on the right-hand side
of the case.
Classic models. Remo e the battery co er on the base of the unit by unscrewing
the retaining stud using a suitable coin or screwdri er.
Fit the battery IEC 6F100 (PP9) to the connector.
Revival models. Close the rear door and fasten the catch.
Classic models. Replace the battery co er and refit the stud.
Reduced power, distortion, and a ‘stuttering’ sound are all signs that the battery
may need replacing.
If the radio is not to be used for any extended period of time it is recommended
that the battery is remo ed from the radio.
We would recommend for economy, this radio is used via the Mains
adaptor whenever possible with battery operation for occasional or stand-
by use only.

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Radio Operation
Your radio is equipped with three wa ebands to enable you to select the
programme of your choice. The FM band uses an external telescopic aerial
which should be fully extended and rotated for best reception. MW and LW
bands are recei ed by an internal aerial which is directional. To achie e the
best reception, it may be necessary to rotate the radio.
1. Switch on the recei er by rotating the olume control clockwise until a
click is heard.
2. Depress the appropriate wa eband button for FM MW or LW as
required.
3. Tune to the desired programme by adjusting TUNING control. On
MW and LW the tuning scale is marked in kilohertz (kHz) and on FM
in megahertz (MHz).
4. Adjust the olume and tone controls to the desired tone and sound
le el. Depressing the TONE control button reduces high frequencies
(treble).
Headphones
A 3.5mm socket is pro ided for use with either headphones or an earpiece.
Inserting a plug automatically mutes the internal loudspeaker.

If you need any further advice, please
call our Technical Helpline on
020 8758 0338 (Mon- ri)
6
Care
For external cleaning use only a soft clean cloth. Use a damp cloth to clean the
cabinet. A mild soap will help remo e grease or oil. Ne er use strong detergents,
spray cleaners, abrasi e powders, thinners or sol ents as these may cause
damage to the radio.
Specifications
Power Requirements 9.0V DC
Battery 1 x IEC 6F100 (PP9)
Battery Life Approx. 80hrs of listening for 4 hours a day at
normal olume.
Circuit Features
Semiconductors 3 Integrated circuits, 1 Voltage regulator.
Output Power 1watt RMS into 8ohms
Headphone socket 3.5mm dia
requency Coverage
FM 87.5 -108MHz
MW 522 - 1620kHz
LW 150 - 281kHz
The Company reserves the right to amend the specification without notice.

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Guarantee
This instrument is guaranteed for twel e months from the date of deli ery to the original owner against failure due to
faulty workmanship or component breakdown, subject to the procedure stated below. Should any component or part
fail during this guarantee period it will be repaired or replaced free of charge.
The guarantee does not co er:
1. Damage resulting from incorrect use.
2. Consequential damage.
3. Recei ers with remo ed or defaced serial numbers.
N.B. Damaged or broken telescopic aerials will not be replaced under guarantee.
Procedure:
Any claim under this guarantee should be made through the dealer from whom the instrument was purchased. It is
likely that your Roberts dealer will be able to attend to any defect quickly and efficiently, but should it be necessary
the dealer will return the instrument to the company’s ser ice department for attention. In the e ent that it is not
possible to return the instrument to the Roberts dealer from whom it was purchased, please contact Roberts Radio
Technical Ser ices Department at the address shown on the back page of this manual before taking further action.
These statements do not affect the statutory rights of a consumer.

ROBERTS RADIO TECHNICAL SERVICES DEPARTMENT
97-99 Worton Road
Isleworth Middlesex
TW7 6EG
Technical Helpline:-020 75 033
Issue 2