Severe corrosion of a printed circuit with exposure to shoreline conditions
The printed circuit board in the photograph here came from an industrial label printer, one used to create labels for our product packages. The printer refused to print for no apparent reason, and despite numerous attempts to update or replace printer drivers, using a different computer, and other fiddling it remained stubbornly inoperative.
So we bought a replacemnt and continued shipping product.
The printer sat in my office for a bit, and one quiet afternoon I decided to do a little forensic disassembly, and scrap any useful bits before I tossed the remaing carcass.
The screws are rusted, the brass inserts darkend with exposure to salt and rain, the post it is clamped to is likewise suffering from corrosion in the salt air, but the 3D print is just fine.
An ABS 3D print that has spent four years in intense tropical sunlight.
Some plastics used for 3D printing decay fairly rapidly with exposure to sunlight and weather. Certianly PLA, the most common 3D plastic, crumbles to dust in just a year of harsh weathering. ABS or Acrylonitrile Butadiene Styrene on the other hand, seems to perform quite well.
Working at Symbrosia I have created dozens upon dozens of designs, many of which are installed in the extremely harsh environment of our outdoor cultivation area. Here the prints sit in intense tropical Hawaiian sunlight for days on end, subject to both intense UV light and high temperatures. The plastic is also subject to continual exposure to salt water used in our operation, or raining from the sky on days with heavy surf, when the waves are crashing just 100 yards away. It does not get much worse than this.
It is always a sick feeling in the gut when a drone goes down.
Removing the gimbal of a DJI Mini 4 Pro
This time it was an unseen branch, a thin and leafless thing that reached well out from the tree, unseen until it was too late. Unseen by the drone’s obstacle avoidance system as well.
I crashed the drone at Panther Falls while enjoying a waterfall day in Southern Washington. A place deep in the trees where a drone pilot is advised to exercise caution. I did, and crashed it anyway.
Designing and building equipment for aquaculture means I use controllers. Quite a few controllers, dozens upon dozens of them, little boxes meant to keep some parameter in range. Temperature, pH, water level, whatever, a little box with a display, a few buttons, and a relay in the back to turn something on when needed to control the outcome.
Industrial suppliers will sell you a controller for just about anything, there are catalogs full of them, from inexpensive to thousands of dollars you can buy the solution to your needs. Buy one, wire it in, adjust a few setpoints and you have everything under control.
Enter the STC-1000, a little cheap temperature controller found on eBay, Amazon, everywhere. It comes in a bunch of different versions, need readout in Farenheight or Centigrade? No problem. I have no idea who makes it, some asian factory somewhere. It is available in a hundred different brand names from hundreds of different sellers for somewhere between $12 and $25, all absolutely identical as far I as can tell.
The STC-1000 is cheap. Cheap enough that I am somewhat suspect of their reliability. I do not buy them for production line bioreactors and grow tanks, places where I cannot trust a cheap controller with a few thousand dollars worth of product. For critical uses I buy full industrial rated temperature controllers from a reputable supplier for around $100 each.
But for experimental setups? Temporary research hacks built with more limited budgets? There are a couple dozen of these STC-1000 controllers around the place. They are easy to use with simple configurations, seem to be accurate holding calibration, and I have not had one fail yet.
So how do you sell a device like this for about $15?
For all of the many times I have done it, I have never gotten tired of typing a command, or clicking a button on a screen, and watching something happen in the real world.
The microprocessor on a GenPIC PCB assembly
An LED turning on, the click of a relay, or even a motor beginning to spin… These represent a moment when the seemingly ethereal digital realm of our computers interact with the physical domain.
I have spent my entire career dealing in the interface between the ethereal and the physical, working where the two meet. Turning sensor readings into digital, and then turning the digital into actions in the everyday world. I played with this interface as a teenager, learning the basics. My wisely chosen college degree was tailored to this task, an electrical engineering degree with a heavy dose of computer science. Professionally I have dealt with microcontrollers, high performance analog to digital systems, and programmable logic controllers, all straddling the boundary line from digital to physical.
It has become apparent to me that what were modern electronics in my youth are now considered vintage electronics. What does that say about me?
A Tektronix 465 oscilloscope
The piece of vintage electronics in question this day is a veteran Tektronix 465 oscilloscope. This particular oscilloscope was purchased decades ago as surplus from Elliot Electronics in Tucson, once my go to place for electronic parts and tools.
pH measurement is a quirky and often frustrating technology. Usually working well, they can go wrong in so many ways. With dozens upon dozens of pH probes in service on the cultivation pads I have now spent a few years attempting to discover all of the ways a pH measurement can go bad.
pH Sim 2 in use checking a Symbrosia Controller
A voltage generated by ion exchange across a glass membrane is the magic that makes a pH probe work, simply measure the voltage and you can measure the hydrogen ion activity of a solution. The result is a number from 0 to 14, with numbers less than seven being acid, and numbers above seven being basic. Most aquatic or marine life, such as healthy algae require conditions close to 7, or neutral, too acid or too basic and everything dies.
I have owned this stereo microscope since I was a teenager. At first used for examining rocks and minerals in my collection, it has found many uses over the years, mostly used during assembly and inspection of various bits of electronic gear. It has been a workhorse microscope, well used, and well loved.
An American Optical model 40 stereo microscope
Despite this it bit me!
I know the feeling all too well, that little 60Hz nibble of 120Vac electrical power, a feeling anyone who has worked with electricity like I have recognizes instantly. Somewhere in this microscope 120Vac power is shorted to the frame.
For someone who works with their hands tools are important. We all have our favorite tools, that one we always use as we have for so many years. There may be a dozen screwdrivers in the rack, but that one is used almost every time.
A veteran Weller WES50 soldering station
Thus is with great sadness that I announce the death of my longtime soldering station.
A good soldering iron is a basic tool for an electronics engineer. A multimeter, a soldering iron, and a set of basic hand tools are absolutely necessary for any electronics workbench. To this end I had bought a very good iron, one that has served me well for several decades.
I wonder just how many soldered connections I made with this old soldering iron… Thousands upon thousands certianly, so many circuit boards, connectors, and wires.
There are no available spare parts for this long obsolete soldering station. There are many conversations on bulletin boards and chat rooms lamenting this as others have had their beloved soldering irons fail. The WES50 was long ago replaced by the WES51, and the parts are not interchangable.
With sadness I remove the old soldering station from the bench. I replace it with a new Weller WE1010NA station. I wonder just what work awaits the new soldering iron, how many solder joints will it see in the coming decades. I hope that this new iron will outlast me.
