Hey Tom, these threads are great because they're not technically complex, 
but do have some depth and rationale involved which make them interesting to 
nearly everyone.
Many of us are responsible for our families vehicle maintenance and it's 
always good to know the logic or procedures behind vehicle related 
maintenance.
Some of us have very capable YL's, some of us have a far more stereotypical 
YL who wouldn't necessarily know the difference between a car battery and an 
air filter...so the info from this list is invaluable for many.

73
Colin, V A6BKX
--------------------------------------------------
From: "Tom Behler" <[log in to unmask]>
Sent: Saturday, October 25, 2014 8:21 AM
To: <[log in to unmask]>
Subject: Re: Best procedure for connecting and disconnecting a 12-volt 
battery

> Well, Steve, Mr. Murphy does pay a visit here every so often, so I guess 
> one
> of my reasons for bringing up the question was to keep him at bay if at 
> all
> possible.
>
> Also, of course, I'm always interested in doing things the correct way and
> understanding why it is the correct way.
>
> I've never been one just to automatically do what someone tells me to do,
> without trying to have at least some understanding of the procedure, and
> this question has always puzzled me.
>
> It just came up again yesterday, so I thought I'd ask it here.
>
> Thanks to all for tolerating this thread.  I think I've gotten what I 
> need.
>
> Tom Behler: KB8TYJ
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Steve Dresser
> Sent: Friday, October 24, 2014 9:56 PM
> To: [log in to unmask]
> Subject: Re: Best procedure for connecting and disconnecting a 12-volt
> battery
>
> Tom,
>
> From all I've seen in this thread, I guess the answer is that it depends =
> on why you're asking the question.  Often, what we do is determined by = 
> the
> things that can go wrong even though they shouldn't.  In short, Mr. = 
> Murphy
> rules the world.
>
> Steve
>
> ----- Original Message -----=20
> From: "Tom Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, October 24, 2014 21:32
> Subject: Re: Best procedure for connecting and disconnecting a 12-volt =
> battery
>
>
>> Steve:
>>=20
>> My XYL didn't give a definite reason for liking the opposite approach,
>>although I suspect she saw someone do it somewhere, and found that her
>>internet source confirmed what she suspected.  For the record, I still
>>=
> tend
>> to agree with you.
>>=20
>> It's interesting that there apparently are different views on this =
> question.
>>=20
>> And, I appreciate all of the answers I have gotten here.
>>=20
>> If I taught an electronics course, I'd definitely bring it up as a =
> question
>> for debate.
>>=20
>> Maybe it would be interesting to discuss as a tech question at a =
> future
>> meeting of our local ham club.
>>=20
>> Guess it's just the professor in me.
>>=20
>> Tom Behler: KB8TYJ
>>=20
>>=20
>> -----Original Message-----
>> From: For blind ham radio operators =
> [mailto:[log in to unmask]]
>> On Behalf Of Steve Dresser
>> Sent: Friday, October 24, 2014 5:23 PM
>> To: [log in to unmask]
>> Subject: Re: Best procedure for connecting and disconnecting a 12-volt
>>battery
>>=20
>> Tom,
>>=20
>> Although I don't know for certain, I would probably connect the ground
>>=
> =3D
>> first and disconnect it last.  My thinking is that if I connected the
>> =
> =3D
>> positive terminal first, I might end up becoming part of the path that
>> =
> =3D
>> completes the circuit when I connected the ground.  I'm interested to
>> =
> =3D know
>> why your XYL likes the opposite approach.  For all I know, she =3D =
> might be
>> right.
>>=20
>> Steve
>>=20
>> ----- Original Message -----=3D20
>> From: "Tom Behler" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Friday, October 24, 2014 16:37
>> Subject: Best procedure for connecting and disconnecting a 12-volt =3D
>>=
> battery
>>=20
>>=20
>>> Hi, all.
>>>=3D20
>>>=3D20
>>>=3D20
>>> I am sure that, to some, this question might seem to be very =3D
>> elementary,
>>> especially for someone like me who holds an Extra class license.  So,
>>> =
>
>>> =3D
>> please
>>> bare with me, and understand why I am asking the question.  As a =3D
>> college
>>> professor, I always try to teach my students not to simply
>>> memorize=20 procedures or concepts just for the sake of doing so.  I
>>> tell them =
> =3D
>> that real
>>> learning involves understanding the procedures and/or concepts and =
> the=20
>>> reasons behind them.  I also stress that true learning involves being
>>> =
>
>>> =3D
>> able
>>> to apply what you have learned to real life situations.
>>>=3D20
>>>=3D20
>>>=3D20
>>> Anyway, here's my question:
>>>=3D20
>>>=3D20
>>>=3D20
>>> Earlier this afternoon, my XYL and I were in the process of getting =
> =3D
>> our
>>> summer camping trailer winterized for the season, and taken to a =
> local=20
>>> facility for winter storage.  As we worked, it came time to =
> disconnect=20
>>> =3D
>> the
>>> house battery from the unit, so that it can be put on a trickle =3D
>> charger
>>> during the winter months.
>>>=3D20
>>>=3D20
>>>=3D20
>>> Before we disconnected the battery, we were discussing the best =
> and/or =20
>>>safest procedure for doing so.  We never worried about this with the
>>>=20 drivable RV we used to have, because it was always kept in our =3D
>> driveway and
>>> plugged into our main house power all winter.
>>>=3D20
>>>=3D20
>>>=3D20
>>> Anyway, my proposed approach was this:
>>>=3D20
>>>=3D20
>>>=3D20
>>> When disconnecting the battery, disconnect the positive side first, =
> =3D
>> and then
>>> the negative.  The idea here is that you always have the negative or
>>> =
> =3D
>> ground
>>> connected when you're working with the battery.
>>>=3D20
>>>=3D20
>>>=3D20
>>> When re-connecting the battery, I proposed connecting the ground =3D
>> terminal
>>> first, once again, to give you a ground to start from, and then =3D
>> connect the
>>> positive terminal last.
>>>=3D20
>>>=3D20
>>>=3D20
>>> My XYL's approach was the opposite:
>>>=3D20
>>>=3D20
>>>=3D20
>>> She argued that when disconnecting the battery, disconnect the =3D
>> negative
>>> terminal first, and then the positive.  . When connecting, connect =
> the =20
>>>positive first, and then the negative.
>>>=3D20
>>>=3D20
>>>=3D20
>>> As a smart person who has much faith in my XYL's judgment, I decided
>>>=
> =3D
>> to go
>>> along with her proposed approach, and happily, we are both still here
>>> =
>
>>> =3D
>> to
>>> talk about it.
>>>=3D20
>>>=3D20
>>>=3D20
>>> However, I know that I have connected and disconnected many a battery
>>>=
>
>>>=3D
>> using
>>> my initial approach, and I've survived that as well.  Perhaps I just
>>> =
> =3D
>> got
>>> lucky, but I always thought I was proceeding with care, and with the
>>> =
> =3D
>> correct
>>> procedure.
>>>=3D20
>>>=3D20
>>>=3D20
>>> Once again, I hope nobody minds this question, but I consider =
> everyone=20
>>>=3D
>> here
>>> to be knowledgeable on many things, and I trust that you will all be
>>> =
> =3D
>> able to
>>> go with the idea that the only stupid question is a question that =
> goes =20
>>>un-asked.
>>>=3D20
>>>=3D20
>>>=3D20
>>> Your wisdom on the topic would be most appreciated.
>>>=3D20
>>>=3D20
>>>=3D20
>>> Thanks for listening.
>>>=3D20
>>>=3D20
>>>=3D20
>>> Tom Behler: KB8TYJ
>>>=3D20
>>>=3D20
>>>=3D20
>>>=3D20
>>>=3D20
>>>=3D20
>>>
>>