Inspection Procedure 8: There is More Noise on Either AM or FM.
DIAGNOSIS PROCEDURE
There is much noise only on AM. Due to differences in AM and FM systems, AM is more susceptible to noise interference.
STEP 1. Check that there is noise under the following state(s).
- A motorcycle was passing.
- Lighting was flashing.
- A vehicle passed close by, but it appeared to be a vehicle generating a particularly large amount of noise radiation.
- Passed beneath a power line.
- Passed beneath a telephone line.
- Passed close by a signal alternator.
- Passed close by some other sources of electrical noise.
- Passed under a bridge.
Q.
Is there noise in the above states?
Go to Step 3.
Go to Step 2.
STEP 2. Continue to check for static; when static is detected, check for the conditions listed above.
Q.
Is there noise in the state described in Step 1?
Noise prevention on the radio side is difficult. If the problem is particularly worse than other radios, consult a service centre.
Go to Step 3.
STEP 3. Check noise prevention on the radio side is difficult.
Q.
Is the noise level worse than other radios?
Consult a service centre. Noise encountered during FM reception only. Due to differences in FM and AM systems, FM is not as susceptible as AM to interference from engines, power lines, lighting, etc. On the other hand, due to the characteristics of FM waves, there are sometimes cases of noise or distortion which are generated by typical noise interference (first fading and multipath). Noise (hissing) occurs in weak signal areas such as mountainous regions, but this is not due to Furthermore, the amount of interference will be comparatively less for vehicles equipped with a diversity antenna system*. If there is an equivalent amount of distortion in vehicles or radios of the same type, then differences will be because of differences in antenna systems, and this should be explained to the user. a problem with the radio. Furthermore, the amount of interference will be comparatively less for vehicles equipped with a diversity antenna system*. If there is an equivalent amount of distortion in vehicles or radios of the same type, then differences will be because of differences in antenna systems, and this should be explained to the user.
If the noise level is roughly the same as other radios, there is no action to be taken.