Any Electricians? Help n advice needed!

[Steve Smith]

I need to work out if my daughters portable DVD has a positive centre pin or negative for the power source. It does not have the symbol to illustrate what it should be. I have bought a universal car adaptor to replace the broken LG one and dare not get it wrong way around. As a rule is there a common one to use?
It is a LG371p model.

I am looking for a symbol like the one below but cannot find it.

+-0)- -

[Steve Smith]

Sorry if its in the wrong forum!

[N Dentressangle]

Centre pin's normally the positive, AFAIK

[philthy]

The centre pin is almost always the positive.
The reason I say that, is that in all the years I've been involved with them, I can only ever remember one that wasn't.

[NiceCupOfTea]

Casio keyboards were centre neg and all other ones were centre pos! Ended up with many blown keyboards in schools

Shouldn't most stuff have polarity protection? Surely you'd just need a diode or two?

[tubbystu]

Steve Smith said:

...replace the broken LG one......

How broken is it ? And have you got a multi-meter ?

Can you do a continuity test between the 13a plug and the dc socket on the old broken one ?

You only need one leg to respond to know.

[Steve Smith]

My daughter managed to unscrew the end causing the spring to ping the contense to distribute itself within the car. I found most but the retaining collar has vanished.

The good news is the universal one i bought from amazon works just fine, in some respects it is much better than the LG cable. I took a gamble based on your replies and hooked it up with a positive centre pin arrangment and all seems fine. Thanks