Always check your earthing

The modern DSO (Digital Storage Oscilloscope) is a powerful diagnostic instrument well suited for diagnosing hardware but there are traps for young players the most insidious of these is differing earth potentials. If you get this wrong you can easily release the magic smoke from a circuit and worse still put your life in potential danger.

This week's adventure started with a Rigol DHO924S a perfectly adequate 12bit 1.25GSa/S scope for most tasks (except for the one I really want to use it for) and just before connecting up the signal probe earth to the USB powered microcontroller circuit I did my usual check with a multimeter of the difference of the zero volt on the circuit under test and the signal probe ground wire. 88 volts. A scarily large number for a sensitive device under test. While in this case the connection would probably have been safe, good practice made me change the supply arrangement - just in case. Read More...

Golang compiler CLI options CGO_CFLAGS_ALLOW

I do a lot of building Golang across platforms (honestly I just prefer the work flow under OS X) but frequently you see messages like

% go build
gopkg.in/gographics/imagick.v3/imagick: invalid flag in pkg-config --cflags: -Xpreprocessor


And then Google fails me when you search for the error. It turns out the problem is trivial to fix and that the specific Google search finds lots of things relating to things other than the problem.

The solution:

% env CGO_CFLAGS_ALLOW="-Xpreprocessor" go build


Read More...

Your top priority is ...

One of my favourite aphorisms is

If you have two top priorities you don't have a top priority

A situation that arrives all too frequently is that everything is important, resources are limited and changing priorities lead to relative inaction on anything.

This week's Agile Mentors Podcast provided an insight from the Marines (#170: Leadership Lessons from the Marine Corps with Tanner Wortham) about how having a goal and pre-declaring which other goals should be sacrificed (if necessary) provides a way to make progress.

Read More...

Say it aint so ...

The click bait got me …

Australia named world’s second safest country in new global travel ranking
Ben Cost | National News Network
November 21, 2025 2:35 pm

How could it be so … we have snakes, spiders, sharks, crocodiles and even mean kangaroos … how could this country be almost as safe as the Netherlands? Read More...

We care about your security ...

One of Australia's big 4 banks (NAB) acquired Citi Bank's credit card operation. At a moment of great change they are creating an opportunityfor scammers. Here are some of the issues that have arisen:
  • Picking an extremely generic and common name for their new service rebrand (MyCard)
  • Sending communications which warn of future changes, requiring you to act but do not say the actions required are not possible yet
  • Not making available placeholder applications / websites and clearly linking to them (or saying they are not there yet) from existing trusted sources
This is an invitation to scammers to take advantage of the confusion.

Caring about your customers cybersecurity must not be just a marketing slogan.
Read More...