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External components of a Mac or a PC

The different external components are:

Input peripherals

Graphic tablet
Touch screen
Audio/Video input card

Output peripherals

Video display
Fax modem
Network interface

External storage

Hard disks
Removable storage devices
Floppies and similar storage devices
Flash drives
CD/DVD burners

External connectors

Input peripherals: Haut

They are used to input information: keyboard (text input), scanner or camera (image input), microphone (sound input).

Keyboards Haut

Due to the lack of direct vocal encoding, the keyboard is THE input device for text.

The best of the keyboards: 10 years of hard working before death ;-)
This an Apple pro keyboard: more than 300 euros ten years ago.
Two ADB connectors: one on the left, one on the right -> we can put the mouse where we want!

The worst ADB Apple has never produced: awfull key rendering, noisy, ADB connector on the rear... :-(

USB keyboard of the early iMacs: connectors on left and right... back to user friendly design :-)

The transparent PRO one: big function keys... but very quickly dirty.

A Macally keyboard. Very good.

And now, one can find wireless keyboards or one can use USB PC keyboards.

Mouses Haut

From left to right: a MacPlus mouse, one of the last Aplle ADB mouse, the first Apple USB mouse and the Apple basic optical mouse.

If you have to change your mouse, I would suggest the optical choice... but not the Apple one.
Optical because no wheel, no dust...
Not Apple because the Apple one is expensive, delicate, has a very short cable..and only one button.
For instance Logitech brand mouses are very good...

... here it is.
The "plus": light, optical, long cable, 3 buttons (avoid to use CTRL-click to bring up the contextual menu), a wheel (for text scrolling)... and around 20 euros.

One can alos find wireless mouses. Either optical one (infrared) or Bluetooth based (radio frequency).
In both cases, the mouse must analyze signal it receives -> the mouse must be powered: batteries (rechargeable or not).

A USB trackball.

A USB graphic tablet. Many people who has one does not use the pen... and are happy: (1) not have a wire to the mouse and (2) not be forced to use batteries!


This peripheral is used to scan a image lied down on a glass and memorises it in the computer.
The image can therefore be manipulated by special tools: for instance a photo manipulation software or a software being able to extract text from an image (OCR).

In the past, they had a SCSI connector. Now they use USB or Firewire.

Several points can help to select a scanner to buy:
[1] Its resolution.
The higher it is, the easier the scanner will have to zoom parts of the image you want to import. It is important to pay attention to the scanner's real resolution: sometimes, salesmen speak about an (computed) interpolated resolution. The scanner computes new points to artificially increase its resolution (for zomming for instance) but the more it does that, the lower is the quality of the result.
[2] Next point is the scanner's abilty to take the high and low lights into account.

Audio/Video input devices Haut

Such devices help you to enter images/fims or sound form several sources (TV, camera, ..) into the computer.
Either they are "pro" (and therefore expensive), either they have a limited use (home use) and they cannot handle a huge amount of data.

Output peripherals: Haut

They allow to extract information from the computer and send it on the screen, on a printer, on a fax, on a modem or a network.

Video displays

At the very beginning, Apple use a proprietray DB 15 connector system which forces mac lovers to pay expensive prices for display monitors. For instance, in '91, a 13'' display monitor cost 800 euros. i.e. the actual price of a low end eMac !

Then next, Steve starts to think... -> the VGA connector, the same as the Empire has, is used on Mac. More, the DVI one is also used: this Digital Video Interface transmits numerical signal and not analogic one!

Then, Apple comes back to its bad "proprietray" pratices: the ADC strikes back -> so to connect a modern display monitor to a (?modern?) Mac, we have to insert a DVI -> ADC adapter (150 euros).
ADC = DVI + power wire in the same cable...the big disavantage is to require special graphic cards... which, on Macs, cost twice the price of the equivalent graphic card on PC... just for a different ROM !

-> So, before using a new monitor, check the connectors!

Fortunately, on modern Apple monitors, standard DVI connectors come
back !

Printers Haut

Printers were first connected through a serial cable (mini-din 8) or through a LocalTalk network. With iMacs, arrives the USB standard...while the ethernet was still wisdzly used;-). Once upon a time, on Mac machines, one cwas able to use infrared connection to print, but now this type of connection has disappeared: Bluetooth connection is the "up-to-date" fashion.

We have inkjet or laser printers:
1. Inkjet printers are cheaper..but cartridges are expensive.
2. Laser printers are more expensive to buy (especially color laser) but are less expensive to use. Unfortunately, colors laser printers commonly over saturate the colors.

Modem/fax Haut

In the past, they were external devices, connected on the serial port and expensives (let's say, 8 years ago, 250 euros for a 14.400 bauds modem... 4 times slower than the standard RTC modem you can fine in iMacs). Now, all of the modems are connected to the USB: either they are really USB ones, either they need a USB to serial adapter.

To send a fax, you need a modem but also a standard phone line: fax cannot be sent through a DSL or cable modem!

Network interfaces Haut

Always, the Mac was a communicating machine. First we have AppleTalk protocol in a localtalk network: easy but not quick, one can share files or printers.

Then come network cards, first in BNV with coaxial cables.
This system is based on a token ring. Main disavantage, if transmissions in cable are interrupted, the network is down :-(

Then the base-10 RJ-45 , followed by the base-100 and base-1000 network.
A star based network with a hub/concentrator in the center: if one machine has a problem, other ones are not affected.

Now, we have wireless networks: with airport 802.11b (11 Mbps in theory..6 in pratice !) and airport extreme 802.11g (54 Mbps in theory... 30 in reality !). They are based on radio frequencies in the range of the 2.4 GHz. Machines in a radius of 300 meters can be connected to the same station.

There is also the Bluetooth system (1 Mbps in theory) but not so far network minded: more for cellular phones, peripherals (printers,..), ...

And now Apple is focusing its attention onto FW-based networks.

External storage Haut

To store data for backup, exchange data from one machine to another or simply to have an extra capacity.

Hard disks

Short description. There are 3 types of external hard disks:

  • USB
  • Firewire
  • SCSI

SCSI: very expensive.
FW: 400 and 800 (around 30 Mo/s).
USB: USB2 (60 Mo/s in theory; 15 Mo/s in reality) and USB 1 (1 Mo/s; too slow; forget it as far as external disks are concerned).

Note that, in general, USB & FW external drives are not totally USB & FW but contain a EIDE-> USB/FW internal bridge !

4 types of external disks: from top to bottom: an 2.5'' in a FW box, a 3.5 '' EIDE in a FW/USB1 box, an SSCI one in a powered box and finally anothe SCSI disk.

Face view. About capacity:

  1. 10 gigas
  2. 60 gigas
  3. 1 giga
  4. 500 megas

  1. FW (firewire)
  2. USB 1
  3. SCSI 50 pins
  4. power conector
  5. ON/OFF switch
  6. SCSI terminator
  7. SCSI Id selector

Removable storage devices Haut

The most commonly used removable storage devices (tapes drives, less used for domestical purposes, are not shown):

  1. Floppy: here an HD (1.4 Mb); before floppies were 5'' flexible supports; no longer used since iMacs!
  2. ZIP(Tm) (100 Mb, 250 Mb): "supper" floppies; delicate and flexible.
  3. Magneto-optical cartridge: sure, big capacity but slow; for backup purposes; same as actual CD-RW.
  4. SYQUEST(Tm) (44, 88 and 200 M); a hard disk plateau within
    an cartridge!
  5. JAZZ(Tm) (1 or 2 G).

The only removable storage devices which has survived is the ZIP... despite all its weaknesses.

Compact Flash USB reader (with a 64 Mb card). That's the tendency of the moment: FLASH memories within keys, cards,... 32/64/428/256/512 M are common; 1 G are still expensive.

I would prefer the card+reader choice: less expensive, reader is faster, you can use the card directly in modern PCs or laptops... not in Macs!

No mechanics inside -> more resistant, less cumbersome... but more expensive.

 CD and DVD Haut

The most widely used storage support is the CD-R. 700 Mb on it, quick to burn (modern burners run at 52 X) and all the actual machines have one.

-> the solution for transfering data (files, music, games,... ).

Bigger is the DVD (4,7 gigas). Unfortunately, the big problem of the DVDs is the disparity of their formats.
Most of the Macs must use/burn DVD-R, PCs use/burn DVD+R.
Some Macs can read DVD+R, but cannot burn them (except when the burner is "flashed").
Now, double layers DVDs are on the market but with no standard at all.
Newest G5 superdrive cannot handle such DVD, recent PCs built-in burners are compatible !
Double layers DVD are dedicated to store a huge amount of data (more than 8 Gb) and are sepcially dedicated for video films. But unfortunately, such burned DVD cannot be read in most of the living-room DVD players !

Modern burners are now of the USB2 and FW types.

In the past, they were SCSI: 500 euros for a 4X CD-R burner. Yes. Really ;-).
Then next, they were USB1 for the early iMacs... but run away of these so slow (1X in the better cases) machines :-(.

External connectors Haut

Rear face of G4:

  1. 2 firewire ports
  2. one RJ-45 (ethernet)
  3. 2 usb ones
  4. sound input
  5. sound output
  6. RJ-11 modem port
  7. VGA port
  8. DVI port
  9. an PCI card's SCSI port

 Rear face of a G3:

  1. Display monitor's power plug
  2. The machine's power plug
  3. SCSI 1 original port
  4. The ADB port to connect a keyboard/mouse/graphic tablet... and some modems which, beside being very slow, also were powered through this port!
  5. RJ-45 network standard connector
  6. Min-din 9 ports (also called "geoport"): to connect mdeom/printer or a localtalk network
  7. DB-15 Apple proprietary connector welded on the motherboard
  8. Standard input sound device
  9. Cinch input/output and video composite connectors
  10. In and Out S-video ports
  11. A USB PCI card
  12. A FW/USB PCI Card


Titanium rear side:

  1. Power plug
  2. FW port
  3. RJ-45 ethernet port
  4. Two USB ports
  5. A DVI port
  6. one S-Video port
  7. ?
  8. The modem port


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