Electronics on a budget
Equipment is the single most expensive parts of hobby electronics. It
is best not to go the cheap route here as it will save you lots and
lots of hassles and irritations about equipment that doesnt work or
breaks down easely. Still you dont have to spend hundreds of euro's or
dollars to get good equipment.
The most important equipment you need in my opinion is the following:
- Heavy duty screw driver with interchangable headpieces
- General purpose meter (Voltage, resistance, current)
- 30W soldering iron for soldering
- Good large breadboard
- IC remover tool
- Wire stripper
- Electronics tweezer(s)
- Needle nose pliers
- Wide nose pliers
- Wire cutter
- Component cabinet
Tools
Most are pretty standard, Pliers, wire stripper and heavy duty
screwdriver
you probably have lying around somewhere. Its still better to get your
own then constantly borrow your fathers tools as you need them
constantly nearby. Not to mention when your father needs his tools
again or he gets angry when you misplace them.
Soldering iron

The soldering iron is a somewhat difficult point. There are lots of
cheap ones you can get from all kinds of stores but they are
unregulated or quite flimsy, and can break down sometimes (i had mine
die at a somewhat inconvienent moment). I suggest you buy a good one, a
weller is champ of the irons in my opinion and a soldering station is
very good, it can be set to all kinds of temperatures. But they cost a
bundle (especially the soldering stations) but you get quality and they
will last you a long time.
I currently use a cheap iron 30Watts (its a LUX and can be bought at
the praxis line shops in the netherlands), the original tip is horrible
and took very little abuse. The tip was eaten away with several uses,
Solder dissolves lots of metals and tips deteriorates quickly. I bought
a new tip at the local electronics ship that could fit inside. The new
tip is a whole lot sturdier and takes a lot of abuse i have been using
it for a few years.
I also have a second iron, a somewhat more higher quality iron from
antex. Its 15 watts and is geared for SMD work, as you can see at the
very small tip.
Measurement
A general purpose meter can be had very cheaply (7 euros) it can be
handy to buy 2 of them, one for constant measuring of a parameter and
the other you poke around stuff.
Prototyping
Breadboard is handy for prototyping projects, first build them on a
breadboard. If that works nicely, its time to build it on a proto
board. Or etch your own board (thats for another article). Here its
better to get the largest breadboard you can get, the bigger the
better. Why the largest you can get? There is always a moment that you
run out of space for a project, the largest boards are filled up quite
quickly even if you cram a lot of stuff on it.
I have several breadboards.
Storage
Get a big component cabinet for components. I got a 50 tray storage
cabinet for about 30 euros at the praxis (its a dutch shop) they
provide plenty of storage for all your components. The bigger the
better, you can organise all your resistors that start with 47 in one
seperate box, or you can group them in values from 1 to 10, 10 to 100,
100 to 1000ohms.
I grouped the resistors on their first numbers. For example: the tray
47 contains all the resistor values starting with 47, like 4.7ohms
4.7Kohms 470Kohms etc.
There are many kinds of capacitors so i group them differently. Values
from 1000uf to 100uf and that sequence down to 1pf.
SMD components i just keep them in the reel i got them and put them in
a antistatic bag. The reels are cumbersome to store and quite springy.
They get lodged in between the trays damaging the reels and sometimes
spilling out the components. I also have a lot of boxes with large lots
of components, recently i got a resistor kit of 100 metal film
resistors per value, totaling 6200 resistors. The box i use also for
large quantities of components and chips.
Components
When starting out its always handy to get an so called resistor kit. It
contains a large selection of commonly used resistors (about 30 kinds
in quantities of 10). You restock that selection once in a while. The
same exists for capacitors, diodes, transistors. The web shop futurlec has an excellent
selection of these kits quite cheap. They should be your starting
point, recycled components can be a hassle sometimes and sometimes the
part you need is not in your junk pile.
Most components can be head cheaply from various webshops.
Ebay is a real goldmine for hard to
get or mass quantities of components for cheap. Look for bargains in
the Business
industrial/electronic components section. There is almost nothing
you cant find. Some ebay sellers that have interesting stuff.
- MChoward
electronics. Sell large kits of logic chips. Look for "TTL" or
"Logic" on ebay for more bargains.
There are lots of other ebay sellers that sell large quantities of
often used
components very cheaply. Most of them send them quite quickly but you
need to make a ebay and paypal account, a creditcard is also handy in
this case for fast payments. Just use the search function on ebay.
Recycling
Yes recycling is the other great source of difficult to find or cheap
components, some components are really not worth the effort of
salvaging. Resistors comes to mind, they can be had for very low
prices. I buy them at farnell for prices like 2 eurocent per resistor
(minimal quantity is 50 pieces).
The parts that are worth salvaging are:
- IC's
- Most transistors
- Heatsinks (With the component attached)
- Inductors
- Transformers
- Big capacitors (foil and electrolytics).
- Motors
- Gears
- Sensors
- Neodymium magnets
The above components cost a premium or are easely extracted.
IC's can be a problem sometimes, but can be extracted easely with a
paint stripper heat gun. You just heat the legs of the chip up to a
certain temperature so the solder starts to melt and you can remove the
chip with ease. Work with 2 people, one as the heater, the other as the
chip remover. This way you can extract heaps of chips this way.
Specialty or power transistors are sometimes expensive. Power
transistors are easely extracted with their heat sink. You just apply
some solder to the solder joints so you get a thick solder joint. This
excess of solder makes it easyer to suck the solder up with a solder
sucker. The component isnt usually completely free but with some pliers
you can loosen the leads from the board.
Specialty transistors like RF transistors are a prize, but extract them
carefully they are more sensitive but you can extract them the same way
like you do with normal transistors.
Inductors can be useful for your own switch mode power supplies. And
they can be quite pricey.
Transformers can be handy, for winding your own for instance. The
previous windings can be loosened if you boil the transformer for a
while in a cup or pan of hot water. This will loosen the glue keeping
the transformer together. This only works for ferrite transformers.
Big capacitors are usually easy to remove from a board as they are big
and can be grabbed while unsoldering. (watch your fingers!)
Motors, gears and other mechanical stuff are very useful for robotics.
You dont come across sensors often but are handy and should be removed
right away. There are tons of applications for those.
All kinds of appliances have all kinds of components. Here is a small
list what you can expect from them.
This list is not exhaustive but these are what i found of use:
- Television: lots of
capacitors, nice infra red reciever, high power high voltage
transistors, some linear regulators, some high frequency transformers,
some oscillator crystals, heatsinks, wires.
- VCR: lots of mechanical
equipment, 2 or 3 motors, one high speed brushless DC motor, optical
sensors, nice transformer, lots of leds, pushbuttons, crystals.
- computer power supply: A
few high power diode's, power inductors, a comparator IC, PWM
controller IC, heatsinks a real treasure trove for PSU building.
- Harddrive: Neodymium
magnets that are difficult to remove, but when you soak the complete
assembly in acetone you can get them loose, acetone dissolves the glue
(and skin oils, so use some handcream afterwards) . The PCB contains a
bunch of usable SMT components, cheaper then buying them.
- Floppy, CD-ROM drives:
Motors, motor controller, sensors, maybe a nice laser (Be very careful
with those!), nice neodymium magnets.
- Very old computers: Heaps
and heaps of logic chips! processors, crystals, 100nf decoupling
capacitors, connectors, specialty chips like timers and interrupt
controllers. Here is a small tutorial
to remove those IC's from the boards using a paintstripper. I am
currently investigating removing the IC's with a cooking plate, i will
post results on a seperate page.
Samples
Many semiconductor companies give out samples for free, but some are
quite restrictive about what components they offer. I tend to use this
source of components if there is no other choice or the component i
want is too expensive to be had from distributors or not available.
Some specialty components are hard to get and difficult to find in the
junk pile. Usually IC's are sampled sometimes big power
transistors/mosfets. Please do not abuse this resource to the max,
order as much as you need +1 for an accident. Thats the rule i usually
keep.
Links
Ladyada has a excellent tutorial
about procurement of electronic components, and also a lot of nice
projects.
Inkoopacties is a
excellent site where people group together to get bulk discounts of
various items, lots of them are electronics related. (Dutch speaking)
If i need large cheap quantities of components i usually go to ebay.
This tutorial
is very helpful how to get started and getting good equipment for your
electronics hobby.
Voti.nl is a dutch
webshop with cheap lots, and unusual items (side view motor assembly
from cars!?). Home to a lot of PIC related things, and a very popular
PIC programmer.
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Last update at: 17-06-2005