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To
install dial up external modems, you don't have to know how to
disassemble a computer. If you
feel
uncomfortable opening up your computers cabinet to install a dial
up
internal
modem, then its probably best to purchase external
dial up
modems.
Dial up external modems data and power connections are on the
outside of the computer cabinet. Because of that internal pci
expansion
slots would be kept available for other hardware.
External modems
also have indicator lights on the case so you can see whether
or not you're connected to the
Internet. Being able to
easily remove an external dial up modem would help troubleshoot
both computer and dial up networking problems. |
Forms of dial up external modem
There
are many different types or "forms" modem. The form of modem
defines how modem plugs into the computer. Modem forms are not defined
by their internal processing circuitry. For
example, an internal modem fits inside the computer cabinet
into a
PCI expansion slot.
An expansion slot is an integral part of the
computers motherboard. Since dial up external modems rest
outside the
computer, their forms are defined by how the modems data connection is
plugged into the motherboard. There are only two forms of
external dial up modem. One is serial, the other is
USB. Serial
ports and USB ports are also integral parts of a motherboard.
Some motherboards are still being manufactured with a serial port,
although because of USB porting, serial ports are slowly
getting
phased out of production. |
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External serial modems
External
serial modems have been around the longest.
They earned a reputation for being very reliable early on in dial up
networking history. Not because they were serial ported, but because
external serial modems were hardware
controlled.
External serial
modems do not draw their power from the serial port and need an
external AC power supply. You can manually turn a serial modem on or
off via a switch located at the back. Switching a serial modem off then
on again with force it to reboot.
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A: On/Off power switch
B: A/C power supply
C: Serial port
D: Telephone line
E: Phone handset |
Rear view of a common 56k V.92
dial up external serial modem
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USB
dial up modem
A
USB
(universal serial bus) modem is so named because they connect to any
available USB port on a computer. They were initially available as
desktop models. The latest and more popular form of USB dial up modem
is called the mini usb dial up modem.
Because USB modems can draw their
power and data directly from a USB port it makes them convenient to
transport and share between desktop or laptop computers. USB modems can
be either controller based (hardware) or controllerless.
Make note of
the price of your USB dial up modem when shopping. Price is a good
indicator of the
architecture of a modem. Controller based (hardware) modems are
typically more expensive than controllerless modems. Do some research
before you buy. Check the technical specifications of the modem to see
if you are purchasing a hardware or controllerless modem.
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A: USB port
B: Indicator lights
C: Telephone line |
US Robotics mini USB dial up
external modem
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Regardless of what dial up modem you currently have or want to buy, it
would be
wise to buy a surge protector. Some will accept common residential
phone lines as well as
electrical
plugs. Modems can be damaged from power spikes from near by lightning
strikes. They will also help if you live in a residence that is prone
to other types of electrical power surge. Surge protectors
cost much less than new dial up external modems.
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