Mitsubishi Electric 55624R(S)-MF Service Manual page 133

Is the antenna completely extended?
Does the problem appear only in certain locations
and only with certain stations?
Are connectors properly connected?
Does norse appear when the radio switch is
turned on while the vehicle is stopped and the
radio is struck while tuned away from a station?
Is the radio chassis correctly grounded?
Is the antenna correctly grounded?
(If noise appears when the antenna is moved this
means the ground is not securely connected.)
* A b o u t multipath noise and fading noise
Because the frequency of FM waves is extremely
high, it is highly susceptible to effects from geo-
l o g i c a l f o r m a t i o n s a n d b u i l d i n g s . T h e s e e f f e c t s
disrupt the broadcast signal and obstruct reception
in several ways.
l Multipath noise
This describes the echo that occurs when the
broadcast signal is reflected by a large obstruc-
No
No
Yes
Yes
TSB Revision
Refer to troubleshooting E- 1.
Yes + Due to electrical field conditions.
Check connector connections.
Static electricity noise:
Body static electric from the shock absorber
, rubber bushings used to prevent vibration, tires,
No
etc. occurs because of separation from the
ground, causing a buzzing noise. Since no mea-
sures can be taken on the radio side, steps
should be taken to discharge the static electricity
of the vehicle body.
No
Tighten the screw securely.
If rust is present of the antenna ground screw
clean and tighten the ground securely.
tion and enters the receiver with a slight time
delay
relative to the dierct signal (repetitious
buzzing).
l Fading noise
This is a buzzing noise that occurs when the
b r o a d c a s t b e a m i s d i s r u p t e d b y o b s t r u c t i n g
objects and the signal strength fluctuates intri-
cately within a narrow range.