Calling All Engineers: Share your Must-Have Tools!

My must have tool is the ADALM2000 and I'm not just saying that because I work for Analog Devices!

It’s an unassuming USB-hosted instrument but it has an oscilloscope, signal generator, logic analyzer, network analyzer, spectrum analyzer, etc. etc.

I first got one during the pandemic and used it for practical demonstrations of electronics principles to graduate engineers at our customers who couldn't get into their lab at the time.

It's a great learning tool and there is a wealth of information on StudentZone if you're new to electronics or a little rusty in my case.  I used it regularly in anger when I was an FAE, to look at SPI transactions on an eval board I was debugging, for example.  I'm also using it to validate the performance of a little guitar amplifier home project I'm working on when I get the chance.

My plan is to access it through Python using Libm2k to automate some of my test setups and to manipulate the captured data with Numpy and Matplotlib. MarkThoren thanks for your help with this!

Of course! And I agree 100%, it's the most useful box on my bench, too. I'm debugging a device driver right now with it. Yup I COULD drive to the office and hunt down an expensive logic analyzer, but why?

Get started with libm2k here: https://github.com/analogdevicesinc/libm2k 

Aside from my trusty ADALM2000, it's got to be my the Harbor Freight 7-Function Multimeter, or more accurately, several of them. I have an HP34401 6-digit meter on my bench when I need it, but if a percent or two is all I need, the Harbor Freight unit will do the job.

And... just look at this review!

Awesome!  I got a free one from a colleague as a trade show give-away!  First thing I reach for if I need a quick and dirty measurement.

I am working as a design engineer in the field of industrial precision measurements. So I have often to design analog circuits.
For this I have built two hardware tools:
1.) An improved replacement of a resistance decade box that consists normally on an array of many switches for the resistors.
There are some shortfalls to it:
- When used often the switches get significant and unreliable resistance
- The internal wiring makes up receive and transmit antennas and produce high parasitic inductance and capacitance.

So I built my own box consisting of three high quality potentiometer wired in series with a series resistor.
The potentiometers are compact, sealed metal film 2W with only 100ppm tempco.
The series resistor is 100 Ohm and serves as a protection resistor / fuse against overcurrent. The potentiometers then have 1K, 10K and 100K. The potis have arrow-knobs. To make up the scale for the resistance values I measured with an ohmmeter and draw with an marker lines for 100R, 200R, ...10K, 20K,...
The three potis are housed in a 6 cm x 7 cm box in a triangle arrangement so minimal wire length for series connection is reached.
Advantages:
- Minimal parasitics
- Usable up to several MHz
- Usable for very low voltages that are suceptible to noise
- Quick and continously changeable resistance
- Rugged, higher power handling capacity
- Covers the most often used resistance ranges
- Relatively cheap
* Disadvantage: If you have to know the precise value, you have to measure it.

2.)
As I have frequently to design transmitter and receiver coils that are made up as parallel resonant circuits,
I often need to empirically try out the best capacitance values for it.
The frequencies are several 100kHz up to lower MHz range.
So I designed capacitor switches for it:
There are small hexadecimal coded rotary switches that I use for it.
For the capacitors I use 1% 50V or 63V 0805 ... 1210 NP0. These capacitors I soldered directly to the pins of the rotary switch for shortest possible connection.
For 100pF-1.5nF I use 1x 100pF on Bit0-pin, 2x 100pF on Bit1-pin,... 8 x100pF on Bit3-pin. All Cs packed tightly as possible together.
Then soldered a short twisted pair of leads to it. Finally encapsulate all with hot-melt adhesive.
Built four of them with different ranges: 100pF-1.5nF, 1nF-15nF, 10nF-150nF, 100nF-1.5µF
Advantages:
- Minimal parasitics
- Usable up to several MHz
- Quick variation of capacitance
- relativly good accuracy, only 5pF parasitic, few milliohm series resistance
- relatively cheap

(Lower than 100pF makes less sense because of parasitcs, bigger than 100nF is problematic, because NP0 with higher values get too bulky)

If someone is interested in building these, you are welcomed to contact me: 3d_visions@web.de