Difference between revisions of "TestEquipment"

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With a VNA, you probably want to start with a NanoVNA, before trying to buy an expensive boat anchor with a large footprint.
 
With a VNA, you probably want to start with a NanoVNA, before trying to buy an expensive boat anchor with a large footprint.
  
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* https://theamphour.com/533-microwave-measurement-with-joel-dunsmore/ Amp Hour 533 "Cables are Dogs". Dogs, and VNAs huh...? ... There is a book written by this fellow that would be worth reading if you are working with a VNA (Handbook of Microwave Component Measurements). As noted in the podcast, the first couple chapters are theory, the second section of the book is solving practical problems, and gives specific steps for a given scenario.
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* https://theamphour.com/533-microwave-measurement-with-joel-dunsmore/ Amp Hour 533 "Cables are Dogs". There is a book written by this fellow that would be worth reading if you are working with a VNA (Handbook of Microwave Component Measurements). As noted in the podcast, the first couple chapters are theory, the second section of the book is solving practical problems, and gives specific steps for a given scenario.
 
* https://www.eevblog.com/forum/rf-microwave/inexpensive-cal-standards/ - Notes on cals for VNAs.
 
* https://www.eevblog.com/forum/rf-microwave/inexpensive-cal-standards/ - Notes on cals for VNAs.
 
* https://www.eevblog.com/forum/rf-microwave/how-to-measure-vswr-of-tiny-antennas-how-to-eliminate-effect-of-vna-cables/ - calibrating with antennas
 
* https://www.eevblog.com/forum/rf-microwave/how-to-measure-vswr-of-tiny-antennas-how-to-eliminate-effect-of-vna-cables/ - calibrating with antennas

Latest revision as of 08:17, 23 November 2025

The goal is not to have all of the test equipment, or none, but to have the right test equipment.


Footprint is important. You will want to spend some time thinking about Storage. Try to get equipment that has a digital interface, so that you can automate your setup.

Specific Equipment

Calculators

Current Source

Curve Tracer

Don't buy one without GPIB/USB/Serial. Useless for documentation.

DVM

Density = Mass over Volume. Are you dumb? (The DAM DMV)

LCR Meter

Load

Dummy load in a bucket of water (drum) with enameled wire (must be enameled to allow for the heat to dissipate, whereas plastic coated wire would melt the insulation first).

Of course, you can always use bulbs of a given wattage.

Battery Tester

With some 12V light bulbs, and an analog travel clock, you can estimate the capacity of a Lead Acid battery. Although I don't recommend using an inverter, due to losses. In this case, you are just looking to see whether the battery is near the EOL, or if it is closer to full capacity. You are not going for precision.

Insulation Tester / MegaOhm Meter

A note from Mcmaster: "Over time, insulation may deteriorate which causes resistance to decrease. By periodically testing wiring for changes in resistance, you can identify potential problems, and keep motors, generators, transformers, and other equipment in good working condition." Very clever. I suppose this means the electricians might post the wire resistance on a junction box or whatnot.

Oscilloscopes

It is argued in this thread that: Oscilloscopes take a long time to recover from input overloads, i.e. where the input signal is a long way "off" the top or bottom of the display...

And followed with: That is usually true but not always. Some scopes have front ends specifically designed to handle such situations, so that offset measurements of that kind can be made without the usual issues. The venerable Rigol MSO5000 series is an example.

Pick and Place

Sig Gen

  • https://www.eevblog.com/forum/beginners/what-is-the-practical-use-of-a-function-generator/ general uses ideas for a function generator. One good point, is to get a 2 channel. Another recommendation for the analog discovery (which I've heard a lot about). It seems to be a good general tool. "I happen to use it in audio repairs by following the signal along the tracks" Another good idea. Inject a low voltage conspicuous signal during a repair, and follow the signal path.

Spectrum Analyzers

Functionality

Simply, if you consider a spectrum analyzer as containing a combination of oscilloscope signals, now rotate those signals 90 degrees, and consider that they will be in different places on the frequency axis / x-axis. That is what the spectrum analyzer (or the FFT function of your scope) does. See METE, by K.Brindley 2nd edition, figure 7.1. The book also mentions using an SA for viewing distortion (as an alternative for Distortion Meters). Now where is VR to allow for 360 viewing... The other thing I know is that you want one with a tracking generator (where did I see that).

I suspect that the same physics that control weather and fluid dynamics also relate to electrical signals on an oscilloscope or SA. i.e. interactions can be complex. So ultimately, it isn't that simple. Also consider those physics with with radio.

List

There is the TinySA, similar in idea to the NanoVNA.

Vector Network Analyzers

With a VNA, you probably want to start with a NanoVNA, before trying to buy an expensive boat anchor with a large footprint.

All Purpose Tools

Tips/Techniques

Consider Digital Interfaces for All Equipment

If you want to get serious work done, you are probably going to want to script or automate your setup. So beware of old Bench DMMs, function gens, and other equipment that do not have a GPIB interface (or some similar output).

Output of equipment at 0 Volts

Try to Support Local Businesses

If there is a vendor of a tool or TE near you, then buy from them.

Automation

External Links

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