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For U.S.A. & Canada model
Ver. 2
SERVICE MANUAL Please refer to the
DRA-397
MODIFICATION NOTICE.
MODEL
DRA-297
DRA-37
AM-FM STEREO RECEIVER
For purposes of improvement, specifications and
design are subject to change without notice.
Please use this service manual with referring to the
operating instructions without fail.
Some illustrations using in this service manual are
slightly different from the actual set.
TOKYO, JAPAN
Denon Brand Company, D&M Holdings Inc.
X0282V.02 DE/CDM 0701
DRA-397/297/37
SAFETY PRECAUTIONS
The following check should be performed for the continued protection of the customer and service technician.
LEAKAGE CURRENT CHECK
Before returning the unit to the customer, make sure you make either (1) a leakage current check or (2) a line to chassis
resistance check. If the leakage current exceeds 0.5 milliamps, or if the resistance from chassis to either side of the power
cord is less than 460 kohms, the unit is defective.
CAUTION Please heed the points listed below during servicing and inspection.
Heed the cautions! Inspect for safety after servicing!
Spots requiring particular attention when servicing, such as Check that all screws, parts and wires removed or discon-
the cabinet, parts, chassis, etc., have cautions indicated on nected for servicing have been put back in their original posi-
labels or seals. Be sure to heed these cautions and the cau- tions, inspect that no parts around the area that has been
tions indicated in the handling instructions. serviced have been negatively affected, conduct an insulation
check on the external metal connectors and between the
Caution concerning electric shock! blades of the power plug, and otherwise check that safety is
ensured.
(1) An AC voltage is impressed on this set, so touching inter-
nal metal parts when the set is energized could cause
(Insulation check procedure)
electric shock. Take care to avoid electric shock, by for ex-
Unplug the power cord from the power outlet, disconnect the
ample using an isolating transformer and gloves when
antenna, plugs, etc., and turn the power switch on. Using a
servicing while the set is energized, unplugging the power
500V insulation resistance tester, check that the insulation re-
cord when replacing parts, etc.
sistance between the terminals of the power plug and the ex-
(2)There are high voltage parts inside. Handle with extra care ternally exposed metal parts (antenna terminal, headphones
when the set is energized. terminal, microphone terminal, input terminal, etc.) is 1M or
greater. If it is less, the set must be inspected and repaired.
Caution concerning disassembly and assembly!
Though great care is taken when manufacturing parts from
sheet metal, there may in some rare cases be burrs on the
edges of parts which could cause injury if fingers are moved CAUTION Concerning important safety parts
across them. Use gloves to protect your hands.
Many of the electric and structural parts used in the set have
Only use designated parts! special safety properties. In most cases these properties are
difficult to distinguish by sight, and using replacement parts
The set's parts have specific safety properties (fire resis- with higher ratings (rated power and withstand voltage) does
tance, voltage resistance, etc.). For replacement parts, be not necessarily guarantee that safety performance will be pre-
sure to use parts which have the same properties. In particu- served. Parts with safety properties are indicated as shown
lar, for the important safety parts that are marked ! on wiring below on the wiring diagrams and parts lists is this service
diagrams and parts lists, be sure to use the designated parts. manual. Be sure to replace them with parts with the designat-
ed part number.
Be sure to mount parts and arrange the
wires as they were originally! (1) Schematic diagrams ... Indicated by the ! mark.
For safety reasons, some parts use tape, tubes or other insu- (2) Parts lists ... Indicated by the ! mark.
lating materials, and some parts are mounted away from the
Using parts other than the designated parts
surface of printed circuit boards. Care is also taken with the
could result in electric shock, fires or other
positions of the wires inside and clamps are used to keep
dangerous situations.
wires away from heating and high voltage parts, so be sure to
set everything back as it was originally.
2
DRA-397/297/37
ADJUSTMENT
Idling Current
Required measurement equipment: DC Voltmeter
1. Preparation
(1) Avoid direct blow from an air conditioner or an electric
fan, and adjust the unit at normal room temperature 15