Hardware Reference
In-Depth Information
here are also ive-band resistors. You read these in the same way as a four-band resistor,
except that the irst three bands ofer resistance igures, the fourth the multiplier, and the
ifth the resistance.
Sourcing Components
If you haven't dabbled in electronics before, it can be diicult to ind components and tools.
hankfully, there are plenty of online and oline sources that specialise in the hard-to-ind
components you might need to complete your project.
Online Sources
Two of the largest retailers of electronic components and tools in the world are
RS Components
and
Farnell
. Both operate oices and warehouses across the world, and both have a substan-
tial selection of hardware from which to choose. Chances are you're familiar with at least one
of the two retailers. At the time of this writing RS Components and Farnell were the only two
companies licensed to produce the Raspberry Pi hardware by the Raspberry Pi Foundation,
so unless you're reading this topic while considering the purchase of a Raspberry Pi, you'll
have ordered the device from one of the two.
Both RS Components and Farnell focus on
business-to-business
transactions, meaning that
their main source of income is from electronics companies buying large quantities of compo-
nents. However, both will happily allow consumers to register with their respective web
stores and place orders as small as individual components.
When you're placing small orders, be aware that there may be additional charges incurred. RS
Components charges for its next-day delivery service, and while the charge is quite reason-
able for larger orders, it can cost signiicantly more than the components being purchased
for smaller orders. On the other hand, Farnell doesn't charge for next-day delivery but does
mandate a minimum total value for orders placed through its website.
Depending on where you live, you may be able to reserve items for collection at one of RS
Components' or Farnell's trade counters. his saves on the cost of postage and gets you the
goods faster, but it may not be an option at your location. he websites for both retailers can
be found here:
RS Components:
http://www.rs-online.com
Farnell:
http://www.farnell.com
