Major Newb Questions

[CircuitCurious]

So I'm pretty new to electronics, circuitry and electricity. I've had the pleasure of working on a bridge project using a Vex kit and RobotC to build an autonomous bridge. I have had a lot of fun working on the project, but being a University course, it was fairly guided, so my knowledge of these wasn't developed much beyond what we needed to do.

I'm looking to get started with my own electronics hobby, but first I need to acquire some hardware. I'm hoping that the all the knowledgeable folks here could help me figure out what I'll be needing based on some of my envisioned projects:

-Basic lights/sensor circuits
-Home made alarm clock
-Wireless motion detector
-Remote controlled car (distant future)
-Solar panels (distant future)
Anything else to suggest for a newbie?

So far I've concluded that I'll need:

-Multimeter (I'm still really unsure, Fluke 177/179 seems to have plenty of extra features...But I don't know if it's really worth the investment)
-Breadboard
-Wires and alligator clips
-Resistors
-LED Lights
-Sensors
-Soldering iron
Do I need anything else?

I still don't understand what the real world uses are for an Oscilloscope and whether I really need one.

Whereabouts should I look online for all these things at a fair price? Thanks for helping a newbie out!

 

[Jaguarjoe]

This place has a variety of things as well as pretty good prices:

Electronix Express - Electronics for Schools and Industry

There are many other retailers like Digikey, Newark and Mouser.

Fluke is the gold standard. My 85 is a rugged, reliable and accurate instrument that will outlive me. Buy the best one you can afford. Right now you may think you don't need certain features but you can't predict the future. Frequency measurement is nice to have. An o-scope will allow you to observe waveforms and assess their quality as opposed to just quantity with a DMM. If you shop around pretty nice used ones can be had for less than $150.

Buy or build a dual output power supply, maybe 0-30 volts at 2 amps. You can build or buy a fixed 5 volt supply for uP and logic circuits. Many circuits out there use 3 terminal regulators which are cheap and easy to use.

You'll need some NPN, PNP, and mosfet transistors, diodes, LED's, resistors, capacitors, maybe op-amps, and maybe microprocessors if you want to get involved with them. All of this stuff is cheap.

A few good places to find stuff cheap are Marlin P. Jones & Associates (MPJA) and All Electronics. There are many more.

Don't forget a variable heat soldering iron too.

 

[#12]

10-4 on the Fluke. I bought mine in 1978 and it's never needed a repair!

 

[CircuitCurious]

Thanks for the replies. But could you please elaborate on the oscilloscope? I understand what it does, but what are some regular applications for it? I'm working with a budget right now, so I don't know if I'll be needing one. Should I wait until I can afford a good one for whatever uses it might have later on? I have to choose between a good quality multimeter and no 'scope for now, or an average quality of the two.

The reason I'm wondering is because I'm thinking of getting one of these Fluke 179s which look like a really good multimeter in the long run. But if I'll be needing a 'scope, then I might reconsider spending $300 on a multimeter.

Also, in regards to multimeters, I've been reading about newbies blowing fuses by measuring current with the voltage connections. Has nobody thought around that problem, or would I have to keep switching wires back and forth?

Could anybody suggest some reading material regarding electronics and building them? I understand the theory behind it, but I remember being confused by all the specifications of all the components and what I needed to get.

Are there any good programs for drafting electrical circuits and such, that someone could recommend?

I really appreciate the help!

 

[crutschow]

An oscilloscope is very handy when you are building any kind of AC or digital circuits. Suppose you build a 555 one-shot, for example, and want to measure it's output period. That can only be readily done with an oscilloscope. Multimeters can measure static voltages but, other then those that measure frequency, can't tell you much about varying voltages, which is often as important to know as the static voltage.

If you want to learn about circuit operation then download a free copy of LTSpice. It allows you to draw a schematic of the circuit and simulate its operation before you build. It's also a great way to get familiar with the operation of various types of circuits without having to first build them. I never build a circuit without simulating it first. It will take some effort to learn how to use it, but it's well worth the effort. There is much information and a user group on the Web to help you with any problems or questions.

 

[CircuitCurious]

Does anybody know of a good online resource for learning about electronics and building circuits and such? Like a basic guide and walk through regarding building basic electronics.

 

[Jaguarjoe]

This is pretty good for learning:

**broken link removed**

As far as building stuff, there are 2 ways to go, make "canned" projects that someone else designed, like a Vellman kit, or "roll your own" and build specifically what you want. Rolling your own is far more satisfying but harder. Either way, start simple and ask questions here.

Back to DMM's. Fuses for a Fluke meter are expensive but they do protect the meter. Every now and then Harbor Fright Tools will offer $2 DMM's. It is good to have a few of these kicking around. Its better to sacrifice $2 instead of $200 if your up a ladder and you drop one. They won't have the accuracy or speed of a Fluke but they're not bad.

 

[12345678901234567890]

Another way to learn at a basic level, is buy a cheap multimeter, and purchase one of those electronics learning labs from radio shack, or elenco, then follow there instructions on building a circuit, then it's time to experiment.

Keep a log notebook, then begin to change out components, to see how it affects the circuit performance, and record it in your notebook.

Here is what I did when I knew nothing about electronics.

I bought one of those 130 in 1 labs from radio shack.
Then built a circuit using there instructions, to make sure the circuit worked as specifiede.
Then I began to remove components to see how it affected the circuit, if the circuit did not work, I put the original components back in, then removed another component, if the circuit still worked somewhat fine, I would remove yet another component, I kept on removing components, until I had the circuit working with as least components it could do without, then by having it broken down into it's most simplest form, I began to study it by changing values of the components that were left, and recording what the circuit did, kept doing this until finally I had some idea how the circuit works and why it works with the components that were originally in the circuit.
But always remember to keep a log of major changes to refer back to when studing this circuit.

 

[Diver300]

10-4 on the Fluke. I bought mine in 1978 and it's never needed a repair!

I am fairly sure that the Fluke 85 came after the Fluke 73, and that the Fluke 73 came out in about 1983

Good multimeters anyhow.

 

[CircuitCurious]

Great resource Jaguarjoe, and thanks for the advice about the Fluke, but I'm not too worried about it.

In regards to getting a starter kit, I can't seem to find one online. I'm planning to order that Fluke DMM kit online from Neward, Mouser or Digikey, but I can't seem to find any generalized circuitry starter kits with all the basics. Could anybody help me with this? I really appreciate it. I did check my radio shack, but they didn't have anything of this nature. :/

 

[CircuitCurious]

Is 1 mA bottom range good enough? Or will it limit me with projects?

 

[Jaguarjoe]

Is 1 mA bottom range good enough? Or will it limit me with projects?

A 1ma range on a 3-1/2 digit DMM will work for 99.9% of what a hobbyist does, but if you need to measure current beyond the range of the DMM, use Ohm's law to select a resistor of appropriate value, place it in series with the circuit, then measure the voltage drop across it. I=E/R, if you know R than I and E are proportional to each other.