Gotta keep 'em regulated
Some circuits like only pure DC and the digital side can spit the dummy with any noise riding on the DC, as in ripple due to poor filtering/feed back loops
I got a mate telling me this story of how his car died because the timing belt failed. Something ceased causing the teeth to rip off the belt. He then reckons his stereo volume turned down, and the music from the CD player slowed, like slowing down a tape. He was obviously referring to his alternator failing, but I never knew it was possible to slow down the speed of a spinning CD to make the sound also slow. I reckon he's full of shit, but I can't find any cases of this happening before.
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Gotta keep 'em regulated
Some circuits like only pure DC and the digital side can spit the dummy with any noise riding on the DC, as in ripple due to poor filtering/feed back loops
Reality is an invention of my imagination.
ಠ_ಠ
Smacca (02-03-11)
Can't say i've ever heard of a carcd player slowing down. Your right he must be full of sh!t.
Mickstv
HoleyGrail (26-05-11),Smacca (02-03-11)
Hmm, it could have lagged the processing side of it, after reading the CD. I dunno. He tends to exaggerate the shit out of things.. I'm just not buying this one. I've had plenty of CD players/drives that just won't read a thing if the spin speed is failing or being played with.
Firstly timing belts run the camshafts off the crank, having one fail leads to immediate engine failure.
Yes teeth can rip off but once that happens the engine may or may not backfire through the intake or exhaust but it will stop.
The timing belt does not run the alternator, a v pully or v grooved belt does.
It could be he used the wrong words, his so called timing belt may have been a toothed v pulley belt or glimer belt used to drive the alternator (not a actual timing belt), the car would have run off the battery power not having a working charging system till the battery died.
I would have thought the vehicles ignition system would have failed long before the power needed to drive a CD played was used up.
It is possible... But not at a hardware level... corrupted processing could cause it though - say by a leaky alternator diode causing ripple on the 12V, coupled with shitty regulation in the CD player
Reality is an invention of my imagination.
ಠ_ಠ
Godzilla (02-03-11)
I would have expected the data errors if occuring would be causing symptoms similar to a scratched disc.
Mickstv
Reality is an invention of my imagination.
ಠ_ಠ
Your right though the Quality of the unit could very well be suspect.
Suspect laser ? ?
I'm a little off topic but anyway.
I remember years ago I repaired a Panasonic home CD player. It had bad hiss on both outputs but still played disc's ok. The hiss was caused by bad ripple on the rails from the mains transformer due to faulty caps.
Mickstv
Last edited by mickstv; 02-03-11 at 11:11 PM.
It all happened in a matter of a minute. Timing belt lost grip, alternator stopped working, stereo turned down and slowed music for around 10 seconds then died. I think it's a Pioneer, no idea about the model. Probably about 6 years old now.
He said the timing belt sheared due to a protruding seal somewhere causing friction somewhere. It's a Toyota Camry XV10, so not sure where the alternator/fan belt comes into play, be he reckons its related to the timing belt losing its teeth. He's got it in the shop now, will know the exact cause tomorrow.
Last edited by Smacca; 02-03-11 at 10:22 PM.
My first car had an alternator problem, I noticed it when driving at night with the headlights on, It would struggle to do 80kmh. I had a good battery so the problem lasted for a while before it finally died on me during the day. The stereo i had was alright, amp/sub i noticed at night time the headunit would dim to the beat (as would the other lights in the car) when it started getting real bad the headunit would cut in and out, the speed of playback never slowed down at all, that's something I'd expect from cassette and records players.
godz is correct...
your mate is full of rubbish. at the most the unit would start becoming intermittent...
was he on acid by any chance?
I have witnessed it in battery powered cassette players but digital electronics are a bit different, in that when the correct voltages are no longer present things become intermittent or stop working (can someone clarify??)
but i could be wrong as i am no electronics engineer but have a fair knowledge of things.
Isuzu MU
Yes, you could well be wrong.
The Alternator is is 3 phase. If diodes short and the regulator can't handle it, then you have high frequency ripple super imposed on the DC.
If that ripple is beyond the capabilities of the shitty regulation circuitry inside the deck, then the 5v rails will not be true.
If the 5V logic pulses start getting the odd 3.7~4.2 V supply rather than a true 5V, then the calcs the logic circuits perform will be erroneous.
This can lead to errors in the phased lock loop reading the servo feedback. In fact, the error can snowball as the dodgy logic levels, due to a dirty supply with ripple, provide faulty feedback
Reality is an invention of my imagination.
ಠ_ಠ
Wouldn't the load of the battery help to smooth some of the ripple produced by the alternator ?
Please if I'm wrong explain why because I don't know everything and the more info I find out the better.
Mickstv
It depends on battery size and condition.
It is a bit hard to say without being there at the time, but I wouldn't go writing him of as a loony or a liar.
If, for example, it was the belt turning the alternator breaking , the direction of the alternator may have stalled or reversed. That could cause a back EMF pulse, taking the path of least resistance via god knows what. The stereo maybe?
Reality is an invention of my imagination.
ಠ_ಠ
mickstv (03-03-11)
Thats a fair call.
This thread actually reminded me of a little story. Was going to bendigo one weekend with a mate. Anyway the alternator went crazy all dash lights headlights stereo lights all going from dim to blinding bright and it was boiling the battery. The old ute had a JVC head unit, it never missed a beat on CD or USB inputs.
I can definately see your point regarding poor internal regulation relating to the quality of the headunit.
Mickstv
Sorry KC soft but i also may well be wrong.
What Fernbay is explaining may well be correct.
THIS is why i hang out here, what Fernbay is on about is what i didnt know, you need to be a electronics whiz to know this, most grease monkeys would not have known it.
Interesting and educational information to note.
My thoughts are a simplistic mechanics view of the problem, sometimes the real answer is a little more complex.
i call bs
timming belt sheared = motor stopped
cd player running on battery power only
sorry godz i meant ur correct about the mech stuff.
all in all i feel i've stuffed about with enough cd players and such for it to be my (humble) opinion that a 'slowdown' of the music seems to be pretty much bs.
fernbay, wouldn't this produce a sort of white noise or skipping effect??? not a slowdown of music????????Originally Posted by Fernbay
or would it not read the disc at all as the logic is disrupted wouldn't the ic's controlling the disc reading gear (laser focus, etc) also be affected???
anyone have some cheap cd players they'd care to destroy in the name of experimentation???
i'd really like someone to prove that a slowdown of music playback caused by a power related event is possible on a cd player, that would be really cool!
Isuzu MU
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