This is Apple
Computer's first mass produced
computer the Apple II. It was released in January of 1977 and
took the home computer market by storm. The Apple II offered the
home computer enthusiast what no other computer company to date had been
able to supply, an easy to use home computer with color graphics built
right into the computer at an affordable price.
In early 1977 there were no real personal computers for the average home
user. The market was full of hobbyist kits that took some level of
technical understanding to put them together and there were the big box
systems that were aimed at the business market and cost several thousands
of dollars and even these required an "expert" to set them up. Then along
came Apple with the Apple II, take it out of the box,
connect it to the TV, plug in a tape cassette and viola you have a
computer system in your home.
The earliest Apple IIs were
sold with a number of RAM
configurations ranging from 4K to 48K. This was made possible by a set
of 3 switching blocks on the motherboard, one for each bank of 8
RAM chips in the RAM area. (see the picture above) The
type of RAM chip you used was determined by the switching block
that was plugged into the socket, either a 4K or 16K block. If you used
4K blocks your configuration was from 4 Kilobytes to 12 Kilobytes max.
If you chose the 16K blocks your Ram size was 16 Kilobytes up to 48
Kilobytes. Since RAM was very expensive this system was necessary
to keep the basic cost of the Apple II down.
As prices for RAM dropped
Apple discarded the 4K blocks and soldered the 16K blocks to the
motherboard and the Apple II was factory configured as
16, 32, or 48 Kilobyte systems. The RAM chips were
installed in the sockets for each bank depending on how you
ordered your system. The switching block system was completely done away
with on the Apple II+ as the systems were only sold in the
48K configuration. This is one of the distinguishing features in
determining if you have an Apple II or an Apple II+.
Remember also that only the earliest Apple IIs had removable
switching blocks, later IIs had them soldered in place at the
factory.
There are several other features that
distinguish the original Apple II from the Apple II+. The
most obvious is the name plate on the cover. First there were a few
different keyboards used in the Apple II and II+. The
earliest Apple II keyboards did not have an encoder board
attached to the underside of the keyboard and the lighted power key was
raised up on an original Apple II (see the picture above). The
Apple II+ lighted power key was flush with the case. I've seen a lot
of auctions on ebay selling Apple IIs with the II+
keyboard installed claiming them to be original Apple IIs.
An original Apple II does not
auto-boot to BASIC, it boots to the built in Machine Language
Monitor, known as the Sweet 16 Monitor written by Steve
Wozniak, and fills the screen with random characters. You have to
hold the "CTRL" and " B" keys while turning on the
computer to boot to the BASIC interpreter. This BASIC is
not the same BASIC that is in all the Apple II computers
from the II+ on. The original Apple II BASIC was hand
assembled by Steve Wozniak.
Another characteristic exclusive to
the Apple II is the eight expansion slots are green with bolt
down tabs (see picture above). The II+ expansion slots are black
with no tabs.
This Apple II was purchased at
a local thrift store and added to the museum on February 21, 2003
and came with the original red cover user's manual.
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