Difference between phone and line (modem)

S

Shiva

Hi,

What's difference between the phone and line socket of a telephone modem?
It seems to me that both can be used for connecting to the internet through
an analog line.

Thanks in advance!
 
R

Rene

Shiva said:
Hi,

What's difference between the phone and line socket of a telephone modem?
It seems to me that both can be used for connecting to the internet
through
an analog line.

The phone connector is for connecting Your telephone. That way, if You are
online and pick up the phone by accident, Your connection won't get
"damaged"; the phone is disconnected when the modem is using the line
through the line connector.

Hoping to have been of help to You!
Sincerely,
Rene
 
D

David Maynard

Shiva said:
Hi,

What's difference between the phone and line socket of a telephone modem?
It seems to me that both can be used for connecting to the internet through
an analog line.

Thanks in advance!

The second, 'phone', jack provides a place to plug your phone into, hence
the name, since you used up the one on the wall with the modem cord. The
'phone' jack is also disconnected when the modem goes off hook to prevent
you from screwing up the connection by mistakenly trying to use the phone
at the same time.

As such, no, you can't use both. If you try to use the 'phone' jack for the
modem connection to the wall you'll never get a dial tone since it's
disconnected simultaneously with the modem going off hook. You'll get:
click_________________________________________________________________
 
M

MCheu

Hi,

What's difference between the phone and line socket of a telephone modem?
It seems to me that both can be used for connecting to the internet through
an analog line.

Thanks in advance!

Line connects to the wall socket - the phone LINE. The socket labeled
"phone" is a pass through connection so that you can still connect up
an actual phone to use when you aren't using the modem.
 
J

John Doe

Line connects to the wall socket - the phone LINE. The socket
labeled "phone" is a pass through connection so that you can still
connect up an actual phone to use when you aren't using the modem.

I am surprised, apparently few have used dial-up modems which allow
connecting through either modem jack. I seem to recall having more
than one modem which would allow that.

The likely explanation is that they use interchangeable metal plates
which are all printed/stamped for modems you describe. That is very
common, to use interchangeable parts. Also, I suppose a perfectionist
might get confused if he (or she) isn't told which jack to plug into
the wall.

For what it's worth. I was curious about something similar with
respect to speaker connections. Why do they have a plus sign and a
minus sign on the connections. After asking, I was told that
reversing speaker polarity doesn't cause electrical problems, but can
cause acoustic problems when using more than one speaker.
 
S

Shiva

The second, 'phone', jack provides a place to plug your phone into, hence
the name, since you used up the one on the wall with the modem cord. The
'phone' jack is also disconnected when the modem goes off hook to prevent
you from screwing up the connection by mistakenly trying to use the phone
at the same time.

As such, no, you can't use both. If you try to use the 'phone' jack for the
modem connection to the wall you'll never get a dial tone since it's
disconnected simultaneously with the modem going off hook. You'll get:
click_________________________________________________________________

Thanks to all of you! From now on, I will always use the line jack for
connecting to the internet as suggested by the manual of my modem (but they
didn't explain why:))
 
W

Wayne Fulton

Also, I suppose a perfectionist
might get confused if he (or she) isn't told which jack to plug into
the wall.

That reason must be the most of it. The two connectors are just a phone
line splitter, a simple Y connection. The joint of the Y is the same
phone line, and it doesnt matter which leg you use for what.

It certainly cannot hurt to use them as marked, but it simply doesnt
matter which you use for what. You can be a conformist, or a rebel. :)
 
M

MCheu

That reason must be the most of it. The two connectors are just a phone
line splitter, a simple Y connection. The joint of the Y is the same
phone line, and it doesnt matter which leg you use for what.

It certainly cannot hurt to use them as marked, but it simply doesnt
matter which you use for what. You can be a conformist, or a rebel. :)

It may vary by the model. My current AOpen modem is as you and JD
describe, but some of the models in the past had the connectors very
different in operation. Having them backwards on those would give me
a dead phone, and an error complaining about no dial tone. Given
there are at least two variations that I know of, it just seemed safer
to suggest a method that works for both the variations I'm aware of.
Anyways, plug it in any way you want, if it doesn't work, you can
always swap the cables later.
 
J

John E. Carty

MCheu said:
It may vary by the model. My current AOpen modem is as you and JD
describe, but some of the models in the past had the connectors very
different in operation. Having them backwards on those would give me
a dead phone, and an error complaining about no dial tone. Given
there are at least two variations that I know of, it just seemed safer
to suggest a method that works for both the variations I'm aware of.
Anyways, plug it in any way you want, if it doesn't work, you can
always swap the cables later.

My old SupraMax modem is the same, you will get 'no dial tone' errors if you
plug the line into the phone side :)
 
W

Wayne Fulton

It may vary by the model. My current AOpen modem is as you and JD
describe, but some of the models in the past had the connectors very
different in operation. Having them backwards on those would give me
a dead phone, and an error complaining about no dial tone. Given
there are at least two variations that I know of, it just seemed safer
to suggest a method that works for both the variations I'm aware of.
Anyways, plug it in any way you want, if it doesn't work, you can
always swap the cables later.


Yes, it conceivably might vary, in that modems in the old days did often
use a relay to disconnect the phone jack when the modem was in use, to
prevent extraneous sound from interfering. Obviously that relay would make
a big difference to use of that jack.

But todays modems are constructed much cheaper, and dont spend money on
such relays which are not actually required, and so which jack is used wont
matter today.
 
D

David Maynard

Wayne said:
That reason must be the most of it. The two connectors are just a phone
line splitter, a simple Y connection. The joint of the Y is the same
phone line, and it doesnt matter which leg you use for what.

It certainly cannot hurt to use them as marked, but it simply doesnt
matter which you use for what. You can be a conformist, or a rebel. :)

There may be some el-cheapos that just 'Y' the connectors (super cheap ones
don't even put the second jack on) but most disconnect the 'phone' jack
when the modem goes off hook to prevent the user from screwing up the
connection with the phone.
 

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