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Post by 6HP502C on Jan 28, 2010 11:59:42 GMT
Just curious - sometimes whilst it is speaking, there is a background whine. The pitch of the whine varies in proportion to the amount of torque the bus is putting out. So it the driver is flooring it in a low gear, the whine will be very high, whereas if they are flooring it at a higher speed, it is lower. The less throttle the driver is applying, the lower the whine is.
Is it used to record throttle application and speed?
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Post by londonbusboy on Jan 28, 2010 17:29:18 GMT
iBus has nothing to do with the engine i think. That whine sounds like the gearbox and im guessing the bus is a voith gearbox as they whine.
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Post by greeny253 on Jan 28, 2010 19:28:15 GMT
We get this sometimes on our buses and we use ZF not Voith so it's not isolated. It could be that some of the wires for the iBus equipment are a bit too close to something mechanical but I couldn't say what. The only other thing iBus is linked to is the ignition - turning it off sends the MDT into "Self Holding" mode with a message telling us to activate the ignition to return to normal operation  |
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Post by eggmiester on Feb 4, 2010 16:43:14 GMT
The noise you hear is electrical interference. Its cause by high frequency electrical current (not voltage) and usually affects single core sound/audio cables and coaxial transmission cables. This only happens to devices that use DC Current (Direct Current).
Basically what happens is the electrical field generated by a High Frequency cable, usually a live power feed cable from a Fuse Board or Battery/Alternator terminal penetrates the shield (rubber/plastic coating) of an adjacent Single core or Coaxial (coax) cable, this only happens if the cables are run next to each other. The Penetration generates a very tiny electrical current (usually way less than 0.1mA) in the affected cable. If the cable is connected to a speaker it will generate noise, based on the frequency range the noise will either be a whine or a buzzing sound. If the cable is coax cable the noise will either be dissipated by eletrical ground loop isolation circuits in the consumer unit or amplified if no ground loop is fitted, thus also generating noise.
To rid of this 'noise' a Ground Loop isolator must be fitted, or the offending cables moved away from the main live cable. The whine or buzzing noises will amplify 'go up and down' with engine rev's because the frequency changes as the engine alternator generates more power at higher revs. When an engine is running the alternator takes control of the on board electrical system from the batteries as well as charging them. Thats why some vehicles which are fitted with very high power demanding equipment may be fitted with two alternators.
This is why many car audio equipment installers and those who have installed In Car enteratainment systems will always run the power cables for amplifiers/aux equipment down one side of the vehicle and the audio signal cables down the opposite side.
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Post by Madstuntman on Feb 4, 2010 17:10:54 GMT
The noise you hear is electrical interference. Its cause by high frequency electrical current (not voltage) and usually affects single core sound/audio cables and coaxial transmission cables. This only happens to devices that use DC Current (Direct Current). Basically what happens is the electrical field generated by a High Frequency cable, usually a live power feed cable from a Fuse Board or Battery/Alternator terminal penetrates the shield (rubber/plastic coating) of an adjacent Single core or Coaxial (coax) cable, this only happens if the cables are run next to each other. The Penetration generates a very tiny electrical current (usually way less than 0.1mA) in the affected cable. If the cable is connected to a speaker it will generate noise, based on the frequency range the noise will either be a whine or a buzzing sound. If the cable is coax cable the noise will either be dissipated by eletrical ground loop isolation circuits in the consumer unit or amplified if no ground loop is fitted, thus also generating noise. To rid of this 'noise' a Ground Loop isolator must be fitted, or the offending cables moved away from the main live cable. The whine or buzzing noises will amplify 'go up and down' with engine rev's because the frequency changes as the engine alternator generates more power at higher revs. When an engine is running the alternator takes control of the on board electrical system from the batteries as well as charging them. Thats why some vehicles which are fitted with very high power demanding equipment may be fitted with two alternators. This is why many car audio equipment installers and those who have installed In Car enteratainment systems will always run the power cables for amplifiers/aux equipment down one side of the vehicle and the audio signal cables down the opposite side. Oooooh!! Get you Mr. Know-it-all-pants |
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Post by eggmiester on Feb 4, 2010 19:18:29 GMT
Its amazing what you know!!! Ive worked with mobile sound systems for years and installed many in car systems. I even installed a car stereo for a colleague in BX car park once!!
I did have a peek at wikipedia though to check certain bits of info!
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Post by Madstuntman on Feb 4, 2010 20:19:40 GMT
I did have a peek at wikipedia though to check certain bits of info! Ahhh the truth comes out!!! I know what you mean though I'm useless information on legs!! (funny though... my wife tends to drop the word "information" from that description!!) |
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Post by greeny253 on Feb 4, 2010 21:34:35 GMT
The noise you hear is electrical interference. Its cause by high frequency electrical current (not voltage) and usually affects single core sound/audio cables and coaxial transmission cables. This only happens to devices that use DC Current (Direct Current). Basically what happens is the electrical field generated by a High Frequency cable, usually a live power feed cable from a Fuse Board or Battery/Alternator terminal penetrates the shield (rubber/plastic coating) of an adjacent Single core or Coaxial (coax) cable, this only happens if the cables are run next to each other. The Penetration generates a very tiny electrical current (usually way less than 0.1mA) in the affected cable. If the cable is connected to a speaker it will generate noise, based on the frequency range the noise will either be a whine or a buzzing sound. If the cable is coax cable the noise will either be dissipated by eletrical ground loop isolation circuits in the consumer unit or amplified if no ground loop is fitted, thus also generating noise. To rid of this 'noise' a Ground Loop isolator must be fitted, or the offending cables moved away from the main live cable. The whine or buzzing noises will amplify 'go up and down' with engine rev's because the frequency changes as the engine alternator generates more power at higher revs. When an engine is running the alternator takes control of the on board electrical system from the batteries as well as charging them. Thats why some vehicles which are fitted with very high power demanding equipment may be fitted with two alternators. This is why many car audio equipment installers and those who have installed In Car enteratainment systems will always run the power cables for amplifiers/aux equipment down one side of the vehicle and the audio signal cables down the opposite side. you are wasted as a bus driver man!  |
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Post by lc1 on Feb 5, 2010 0:08:02 GMT
The noise you hear is electrical interference. Its cause by high frequency electrical current (not voltage) and usually affects single core sound/audio cables and coaxial transmission cables. This only happens to devices that use DC Current (Direct Current). Basically what happens is the electrical field generated by a High Frequency cable, usually a live power feed cable from a Fuse Board or Battery/Alternator terminal penetrates the shield (rubber/plastic coating) of an adjacent Single core or Coaxial (coax) cable, this only happens if the cables are run next to each other. The Penetration generates a very tiny electrical current (usually way less than 0.1mA) in the affected cable. If the cable is connected to a speaker it will generate noise, based on the frequency range the noise will either be a whine or a buzzing sound. If the cable is coax cable the noise will either be dissipated by eletrical ground loop isolation circuits in the consumer unit or amplified if no ground loop is fitted, thus also generating noise. To rid of this 'noise' a Ground Loop isolator must be fitted, or the offending cables moved away from the main live cable. The whine or buzzing noises will amplify 'go up and down' with engine rev's because the frequency changes as the engine alternator generates more power at higher revs. When an engine is running the alternator takes control of the on board electrical system from the batteries as well as charging them. Thats why some vehicles which are fitted with very high power demanding equipment may be fitted with two alternators. This is why many car audio equipment installers and those who have installed In Car enteratainment systems will always run the power cables for amplifiers/aux equipment down one side of the vehicle and the audio signal cables down the opposite side. you are wasted as a bus driver man! Well good job he's good at something as it sure ain't bus driving  |
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