The test equipment troll, are you buying the right equipment?

Everyone was the noob at some point; I get it, it’s easy to get hung up on the blinking lights and things with screens but shelf it! You don’t need the $4,000 Agilent or Tektronix scope… though don’t get me wrong it’s on my wishlist too.  I bite my lip on the message boards when I see a new-to-electronics DIYer who wants to buy a Programmable DC Load as one of their very first pieces of test equipment; to troll or not to troll?

What kind of “maker” are you? there seem to be a couple types of DIYers/makers out there. This is my attempt at stuffing you neatly into one or two of these general groups:

1. The arduino/raspberry pi maker.

2. The analog hacker

3. The experienced super nerd/internet “teachers” (FPGAs, 2.4+GHz RF experiments, SDRs, etc.. )

4. Robo-geeks

5. Solar/”Free”-Energy/electric car makers

I don’t really fit neatly into any one category in that list, and perhaps you don’t either? But if you’re truly a noob you’re doing to sit fairly solid into a of those groups; it’s really not group 3 though, right? Where do you fit? Maybe I missed one.. I’m not against revising this blog post to improve it.. got feedback? I’ll reconsider my list.

First off, everyone needs a solderless breadboard. You should have some kind of power supply for it. I recommend one of those cheap power supply boards made for breadboards and fits into both rails of a solderless breadboard that will generate 5VDC and 3.3VDC. Here is an example found at Tindie: Dual Breadboard Power Supply (all links open in a new window). I’ve always used the Jameco or 3M precut wire jumpers because they look nice and when you put them on a soldered protoboard for permanent use they look nice. However, recently I also started using those breadboard jumper kits you can find all over (example). I’ve been won over.. they are a huge time saver. Then purchase your hand tools, a wire stripper, small screw drivers, a small wire cutter.. and so on. Hand tools are something you can probably figure out yourself and you can usually almost everything locally.

Okay, so back to that list of electronics-type internet personalities…

1. So you’re new… who are you? Got that sweet new Raspberry Pi and you’re determined to make it do something cool? Blinking LED light, check! What do you need for test equipment now?

Somethings you’ll need:

Soldering Iron: You’re going to want to interface your Pi to the world, that means adapters, you’re going to have to solder. Don’t invest a ton of money right away, a little 25-35 watt iron will do just fine. Later on you’ll end up investing in some SMD equipment if you start making your own PCBs… wait until you know what you’re doing until you’re dropping cash on a Metcal system.

Multimeter: If you have a nice meter that’s handy but the reality is you’ll probably only be measuring voltage and resistance for the time being. Get something affordable and save your money for the next piece of equipment!

Logic Analyzer: Yep, I know tons of people will disagree but they probably don’t “fit” into the same category as you. I don’t have a logic analyzer, I use a scope and I hate it. I plan on buying a Saleae logic analyzer after Christmas (assuming I don’t get one as a gift). I hate programming my PICs without a LA. I have needed one on the last 4 or 5 projects I’ve worked on. A 8 channel unit will probably work fine, but if you have the cash a 16 channel is preferred. Make sure you can get one that can be set up for protocol detection/translation/monitoring(or whatever they want to call it) like.. make sure it does I2C. There are a lot of used stand-alone units from e-bay: Steer clear! if you have a huge income by a MSO, or a new LA. Those older units usually don’t have (all/some of) the cabling, are missing software, or are going to take up way too much precious bench room.

That’s it besides the common hand tools for small work. You will need other pieces of equipment as you pick projects you’re dedicated to finishing. Wait until then, save your money because you’ll likely find out you need something special and you’ll need it yesterday. Maybe a signal generator? Maybe you’ll cross into the analog work and you’ll need that oscilloscope. I do recommend buying a cheap used Tektronix analog scope if end up needing one. It’s most likely if you’re new you don’t need over 100MHz scope.. then save your cash for the MSO or you’ll just be another guy with 6 scopes sitting around you shop when you could’ve bough a ton of other equipment.

One last tid bit:I lot of new makers are Arduino users, and that’s cool if it got you into the hobby; they seem decent? I don’t own any, I have a love for the PIC microcontrollers, I think you should give them a try sometime.

2. Does anyone just decide to be an analog hardware hacker? Maybe you work on pinball machines, or retro TTL interfacing with old composite TV signals, audiophile, a ham just starting in RF? A lot of options here… this is where I started.

Okay you do need a scope, no way around it. I still recommend a eBay Tektronix scope, or if you have the money go MSO. I don’t trust the cheap Chinese stuff but if you feel comfortable with it, do what you have to do but you’ll probably get better performance out of a Tek 465 or 2246 than you will a $400 LCD toy from overseas. You can usually pick up an old 20Mhz “starter” scope for $20 at a ham swap, I would guess 98% of my use of a scope can be done with a 20MHz scope and for the first few years of my tinkering I never noticed a need for anything more.

You’ll need a signal generator. Used is fine if you trust your scope’s calibration or you don’t need precision… you’ll need a variable power supply, (dual +/-), the multimeter. I prefer using my Agilent bench meter but I also have three Fluke handheld meters. (87, 187, 73). Start out with what you can afford.

You’ll also need a solid soldering iron. I hate recommending these, but if I was I’m partial to the Weller brand. My next iron will be the WD1002. You can start with a 25-35W iron until you can afford more if needed.

I think analog hackers will end up spending the most money out of all the newbies… be careful. It’s easy to spend too much money on equipment you don’t really need and then need a ton more test equipment you have something you need specific to a project and no more cash to buy. Start with the original basics and then buy as needed. If you can save money and buy something that will work for more than just your current project. I keep a running tally of all the projects I’m working on and what I need (or what I think I need!) for them. I generally bulk orders for parts together and if I need test equipment I try to buy something I can use more than once.

3. yeah right, you’re asking the wrong person… fit yourself into a different category if you’re starting out. Take a look at W2AEW’s lab… or that South African YouTube vlogger (mlmorton I think?) .. that guy must have held up a test equipment store..  I can’t even guess how much is labs is worth.

4. Robo-geeks! You’re going to have it rough. You do a little bit of analog work, motor control, digital logic, programming.. I hope you have a lot of money unless you’re content with soldering kits.

You’re going to want to start with a decent soldering iron, you’re going to use it a lot if you’re serious.

A multimeter… that’s it. You need to save your money for all that machining, CNC equipment!

Okay, just kidding, kind of. You will need plenty of other equipment but it’s going to really depend what kind of robots you’re building and at what level. I’ve seen a lot of people crew up and work on certain parts of a robot. Start with the basics and work yourself into what you’re interested in. You’re likely going to fit into one of the first two groups or perhaps both unless you’re just the guy on the controls or strictly writing software.

5. I’m sorry to offend some of you solar or e-car guys sticking you with the perpetual motion machine guys (and gals!). If you’re “making free power” … go get yourself some PPE and a Tesla coil then I recommend a book on Physics and Electronics 101, and call it a day. The rest of you probably don’t really need much past a multimeter. You’ll want something durable don’t go with one of those cheap-o $20 home depot meters.. if anyone needs a bulky Fluke it’s you! The rough environments and mechanical tools boxes.. do yourself the favor. If you find yourself needing something else then go and ask around, but if you’re load testing batteries? Save some cash and go find a cheap load. Small baseboard heaters make cheap loads, you can also get some large surplus resistors at reasonable rates but don’t buy a programmable DC load to test your batteries..

One last thing: Solar Electric?! Unless you have to go off grid (a lot) or you’re rolling in an RV and want a battery charger stop wasting your money. Solar hot water is definitely the way to go as long as you have a decent amount of sun/M2C

Okay, there is a LOT of test equipment out there for you to buy and you will need a lot of it as you take on projects. I have a bench full of test equipment, a bunch on shelving in the garage and I still have a running list of things I want to buy in the semi-near future.. my list:

HV Power Supply
Programmable Power Supply
Programmable Load
MSO Scope
Spectrum Analyzer
RF Signal Generator
Oscilloscope 4 Channel
Arbitrary Function Generator

I have a lot of older equipment, plenty of it was bough for one project and entirely inadequate for others, I also have a lot of ham radio equipment like a HP universal bridge, Bird Watt meter, etc, etc etc.. most of my “affordable” test equipment came from ham swaps and eBay.. ham radio clubs can be a great source for pairing up with people interested in electronics (just avoid the guys with lightbars and more than 3 antennas on their vehicles… trust me.. avoid them).

Oh and on a final note: Dear Tektronix/Fluke, I would will like some of your equipment … a lot of it in fact, used it good! I’m not too picky 🙂 I promise to show it off often and I live like 5 miles away from you.. I’ll pick it up!

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