Grundig Marlborough 3028 Service Manual

Page 1

118 RADIO SERVICING

GRUNDIG MARLBOROUGH Model 3028/W/3D

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General Description: Six-valve (including tuning indicator), four-
waveband (L. W. /M. W. / S W. /V. H. F. ), combined A. M. /F. M. table receiver
with four independent tone controls and three dynamic loudspeakers.
Rotatable ferrite-rod aerial and provision for external aerials Diode socket
for use with tape recorder.

Power Supp lies: A. C. mains, 110 and 190-250 volts.

Valves: (V1) ECC85; (V2) ECH8I; (V3) EM34; (V4) EF89; (V5)
EABCSO; (V6) EL84.

Servicing Notes: R15 provides overload protection for the I. F. trans-
formers and should not be replaced with a resistor rated above13 watt. A
check point is provided for the V. H. F. oscillator, this 13 a small piece of wire
behind C5, C19 from which the negative grid bias can be measured with an
Avo model 8 (20,ooo-ohms/volt) meter (should be approximately 2-5 volts).