Cd Rom in a Cielo?

navin · 28th October 2005, 09:41

dude i had a portable CD player fitted in my car in 1986 thats how old that is.

eagle_f1 · 28th October 2005, 12:11

All this stuff is not that easy as it looks !!!!!!!!!!

Sam Kapasi · 28th October 2005, 12:46

Today MOST portable CD players have anti skip. The discussion is however on Computer CD roms in the car. And I havent seen one with anti skip yet!

Sam Kapasi · 28th October 2005, 12:49

Quote:

Originally Posted by techn0l0gist

somethine similar and better is described here(with pics!):
http://www.sorgonet.com/trashing/enhancedcdplayer/
http://www.sorgonet.com/trashing/Com...ioCDCarPlayer/

:

I do not agree with this post. The CD rom for a computer is designed to run at a regulated 12V, which is generated from the SMPS in the pc. Using the 7805 will definitely generate the 5V required but the 12V will be unregulated. An average running car varies generates 11.8V to 14.4V at the lighter socket (for example)
I believe you will also need to regulate the 12V to the CDrom to never cross 12V. A simple alternative is to use the LM7812 as well.
You see the CD rom needs BOTH 12V and 5V to run.

Sam Kapasi · 28th October 2005, 12:49

Quote:

Originally Posted by eagle_f1

All this stuff is not that easy as it looks !!!!!!!!!!

Thats what everyone told me when I was younger...

Digital Vampire · 28th October 2005, 13:32

Quote:

Originally Posted by Sam Kapasi

I believe you will also need to regulate the 12V to the CDrom to never cross 12V. A simple alternative is to use the LM7812 as well.
You see the CD rom needs BOTH 12V and 5V to run.

If the CDROM Drive can work below 12 V, I agree with using a 7812 Voltage regulator. Though it provides an upper ceiling of 12V, it requires a minimum voltage around ~14.5 volt and higher to give an accurate 12 Volt output. This is due to the internal dropout of roughly 2.5 V in the regulator itself.

So if the 7812 is fed with 12V, the output is going to be much less than 12 V. If the CDROM Drive can tolerate low voltages, no issues.

Also make sure you put oodles of heatzink on the 7805 regulator since its going to get heated up quite high.

Best would be to use some Low-Drop out regulator or better still a switchmode regulator configured in buck-boost mode.

Rtech · 28th October 2005, 13:38

As the whole purpose of this exercise would be to have a cheap DVD player int he car, why not just pick up some cheap Chinese DVD HU instead of trying these tricks?

And aren't CD-ROMS very susceptible to any movement? Any buffering would be a function of the actual music software you use to play it on your PC, so it will have zero shock resistance or buffering when used in a car.

Sam Kapasi · 28th October 2005, 14:17

Quote:

Originally Posted by Rtech

As the whole purpose of this exercise would be to have a cheap DVD player int he car, why not just pick up some cheap Chinese DVD HU instead of trying these tricks?

Well, we're limited to 12v in a car arent we? So if we pick up a cheap chinese dvd (I assume you mean the home kind), that will probably run on 230V, not 12V. That would mean either extensively modifying the internal power supply of the dvd player, or making/buying an invertor that will convert 12VDC to 230V AC.
That kind of again brings us to more spending

Quote:

Originally Posted by Rtech

And aren't CD-ROMS very susceptible to any movement? Any buffering would be a function of the actual music software you use to play it on your PC, so it will have zero shock resistance or buffering when used in a car.

Absolutely

Rtech · 28th October 2005, 14:45

Actually I meant a chinese HU for the car. I've seen some real cheap ones on ebay.

Sam Kapasi · 28th October 2005, 14:48

Quote:

Originally Posted by Rtech

Actually I meant a chinese HU for the car. I've seen some real cheap ones on ebay.

Havent seen them here yet. Anyone?

navin · 28th October 2005, 14:57

Geez. a few weeks ago you guys baulked at changing a cap inteh XO and now you are attempting this!

Ok now that you guys get my attention this is what i know about using a DVD ROM in your car.

1. computer based DVD ROMs are very suseptable to viabration. I mean that some of themy are so bad that even a badly tuned diesel engine can make them skip while idling even the best aren't much better

2. To add any sort of skip protection would require some knowledge of digital electronics and although ready chip sets to do this are available pretty freely it is easier said than done (and guys i got my 1st soldering iron in 1974 or sometime thereabouts).

3. All computer DVD roms require regulatd 12 and 5V signals. In fact I believe they require +12, +/- 5 and GND.

The only advatange (and this advantage can really offset the above disadvantages) of doing this is to have a very funky looking DVD player in your car. That said Rtech, how cheap are the chinese DVD players?

Rtech · 28th October 2005, 15:18

They pop in and out of there. Price? Dunno, but i remember seeing a 5 or 6 followed by a few zero's! I'm the last guy to ask about audio equipement, you guys should know that!

navin · 28th October 2005, 16:07

a few zeros. 3 zeros is 5000! and maybe Rtech you and me should have a little heart to heart. Actually the real evangilist on this forum is Sam. I am a kinder, gentler version. I assure you 30 mins with Sam will change you opinion. :-)

Rtech · 28th October 2005, 16:17

Quote:

I assure you 30 mins with Sam will change you opinion. :-)

Actually it was the other way around. Sam spent one hour with us and he looking more serious than ever. And ever since I've noticed Sam being all serious on the forum! Hmm..I wonder if Rudra's driving had anything to do with that!

mclaren1885 · 28th October 2005, 16:20

Quote:

Originally Posted by Rtech

Actually it was the other way around. Sam spent one hour with us and he looking more serious than ever. And ever since I've noticed Sam being all serious on the forum! Hmm..I wonder if Rudra's driving had anything to do with that!

haha..is it..rudras driving !!!! imagine what psychos driving did to sam...well thats a story i better keep mummm about..or else sam will surely run behind me with a hammer...
PS: btw RT u saw sams video???

28th October 2005, 09:41	#16
navin Team-BHP Support Join Date: Mar 2004 Location: Mumbai Posts: 25,321 Thanked: 9,500 Times	dude i had a portable CD player fitted in my car in 1986 thats how old that is.
	() Thanks

28th October 2005, 12:11	#17
eagle_f1 BHPian Join Date: Dec 2004 Location: Bangalore Posts: 142 Thanked: 13 Times View My Garage	All this stuff is not that easy as it looks !!!!!!!!!!
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28th October 2005, 12:46	#18
Sam Kapasi Distinguished - BHPian Join Date: Jul 2005 Location: Mumbai (but wat Posts: 7,000 Thanked: 2,451 Times View My Garage	Today MOST portable CD players have anti skip. The discussion is however on Computer CD roms in the car. And I havent seen one with anti skip yet!
	() Thanks

28th October 2005, 13:38	#22
Rtech Team-BHP Support Join Date: Apr 2004 Location: Bombay Posts: 5,770 Thanked: 365 Times View My Garage	As the whole purpose of this exercise would be to have a cheap DVD player int he car, why not just pick up some cheap Chinese DVD HU instead of trying these tricks? And aren't CD-ROMS very susceptible to any movement? Any buffering would be a function of the actual music software you use to play it on your PC, so it will have zero shock resistance or buffering when used in a car.
	() Thanks

28th October 2005, 14:45	#24
Rtech Team-BHP Support Join Date: Apr 2004 Location: Bombay Posts: 5,770 Thanked: 365 Times View My Garage	Actually I meant a chinese HU for the car. I've seen some real cheap ones on ebay.
	() Thanks

28th October 2005, 14:57	#26
navin Team-BHP Support Join Date: Mar 2004 Location: Mumbai Posts: 25,321 Thanked: 9,500 Times	Geez. a few weeks ago you guys baulked at changing a cap inteh XO and now you are attempting this! Ok now that you guys get my attention this is what i know about using a DVD ROM in your car. 1. computer based DVD ROMs are very suseptable to viabration. I mean that some of themy are so bad that even a badly tuned diesel engine can make them skip while idling even the best aren't much better 2. To add any sort of skip protection would require some knowledge of digital electronics and although ready chip sets to do this are available pretty freely it is easier said than done (and guys i got my 1st soldering iron in 1974 or sometime thereabouts). 3. All computer DVD roms require regulatd 12 and 5V signals. In fact I believe they require +12, +/- 5 and GND. The only advatange (and this advantage can really offset the above disadvantages) of doing this is to have a very funky looking DVD player in your car. That said Rtech, how cheap are the chinese DVD players?
	() Thanks

28th October 2005, 15:18	#27
Rtech Team-BHP Support Join Date: Apr 2004 Location: Bombay Posts: 5,770 Thanked: 365 Times View My Garage	They pop in and out of there. Price? Dunno, but i remember seeing a 5 or 6 followed by a few zero's! I'm the last guy to ask about audio equipement, you guys should know that!
	() Thanks

28th October 2005, 16:07	#28
navin Team-BHP Support Join Date: Mar 2004 Location: Mumbai Posts: 25,321 Thanked: 9,500 Times	a few zeros. 3 zeros is 5000! and maybe Rtech you and me should have a little heart to heart. Actually the real evangilist on this forum is Sam. I am a kinder, gentler version. I assure you 30 mins with Sam will change you opinion. :-)
	() Thanks