New Projects During the Pandemic

How have you guys been doing during the lockdowns? What projects kept you busy?

I’m thinking of pausing for a while and do some other stuff, like physical activities.

How about you guys? Have you thought about doing other things aside from the projects you’re working on?

When you say “physical activities” I think of bicycling and running. I have done a lot of bicycle commuting in my life but I find the motivation difficult if I am not commuting. So mostly I get to push a lawnmower but we are not in the season for it near Seattle WA.

For home projects I have a fair stash of parts. Much of it is through hole “overstock” from previous employers in quantities which I would never personally exhaust. I like to design around what I have. Often the design differs from what you would do if you were going to buy the parts. So right now I am building a shoe dryer. Powered by a 14 VAC 4 Amp transformer. Not a lot of electronic content and no pcb but for the heck of it I am including a blinking LED power indicator. A blinking indicator is easier to see if it is not so bright. The blinker uses a hand wired LM324 quad op amp in DIP package. One op amp section is the oscillator and the other three are connected in parallel through diodes to drive the LED. After all of this effort I hope it works half as well as something I can buy online for maybe $30. All built with scrap, except for maybe the wood screws. Oh; yes. It is built around a tin which originally was sold containing Chinese “Moon Cakes.” For better or worse, it will be one of a kind.

I have a pretty big project in my hands (product series consisting from 9 PCB’s, 5 embedded software and 6 high level software (and counting)). This takes most of my time. But I’m looking into also engineering management side (as I usually do for my teams). Preparing for a complete remote workforce which will be disconneted from production team.

From physical activity side, I was doing weight lifting and fitness activities before the pandemic. But 2020 has been bad for my health and couldn’t do proper sports activities. Now I feel better and will try to start building some of my lost muscles back. (They moved from my arms to my belly :slight_smile: )

I do strictly analog/power so that embedded software sounds like a technical description of a pillow. :slight_smile:


:slight_smile: I dread to think what would you associate my area with (backend software).

In terms of projects I work on some open source stuff and some of my own pet projects that I sadly can’t open source.
Hardware took a back seat for a bit due to priorities but I have a few things I want to build eventually. Like a smart motorcycle trickle charger. My two wheeled crotch rocket isn’t seeing as much action as it used to since I don’t commute into work anymore and it’s lead acid battery is not too happy about it.

So I just work, code, eat, work out, code, cook, eat, sleep, rinse, repeat. Things like travel or face to face conversations seem like something one used to do in long forgotten past.

1 Like

Not much of a lockdown here in country Victoria, Australia. There were about half a dozen cases in Ballarat 6 months ago, but nothing since. Greater Melbourne has just come out of many months of lockdown and the rumor is we will be able to get rid of these infernal masks in public from this weekend.

No more lawn mowing for a few months as the grass is dead already. It was 32C today, about 90F, so it is looking like a long hot summer again. Not exactly conducive to any form of serious physical exercise. Will have to settle for watering the plants.

Just finished a project. Built a temperature controlled power supply, with readout, using TH components (so I can fix it easily when and if it ever fails) and put it in a box with all my other soldering iron power supplies. Work bench now looks neat. One grey box with one mains lead and several sockets and LEDs, for Scope, Weller and Hakko soldering irons.
There is nothing quite like glowing LEDs for personal comfort and security. My preference is still the red ones. :slightly_smiling_face:

Next project to tide me over summer (and maybe well
into next year depending on how long a list SHE makes for me) will be a new lab power supply with all the bells and whistles I can dream up. This should get me very familiar with 5.1.8 and 5.99 and 6 and maybe even 7 or 8…again, that ever present threat of HER list. :frowning_face:
Sheesh, this retirement is not easy.

1 Like

I’m working on two projects. One is YANC (Yet Another Nixie Clock), a vintage nixie clock with IN-16 tubes, Wifi/NTP, backlit tubes, alarms and stuff. The second is PVS (Precision Voltage Source), a handheld, battery powered, 0-4V 0.1% reference sporting 10µV resolution, OLED display, 5-way navigation switches, USB, PC programmable sequences. Both in 3D printed enclosures.
Could be purchased, no problem. But then, where is the fun in buying compared to making?

After many years layouting pcbs and programming microcontrollers I’m now working for a power electronics company. I have changed mili or micro amperes to tens of amperes, gigahertzs to kilohertzs.

And migrating old analog (but robust) designs to digital resonant converters. And to blink a LED I would use a microcontroller, yes. In fact I cannot remember (or maybe I never knew?) how to blink a led with analog circuitry.

As to using a microcontroller to blink an LED; I cannot imagine. But perhaps we are both guilty of a hammer seeing everything as a nail…

Astable multivibrator circuit? We’d seen that in college but never needed to use one in my designs. Generally used for high frequency but could be used for a blinking LED, too, I guess :slight_smile:

I doubt you are guilty in this case, but for sure I am.
Using a microcontroller for the only purpose of blinking a led it is like killing a fly with a cannonball. I wanted to underline my lack of knowledge in analog elecgronics nowadays.

I remember myself using a 555 as a clock when I was a student. But I would need to study again to make it work!
Those lessons are more than slept somewhere hidden in my brain, if by chanxe they are still there.

I can.
It’s a very important part of almost each project.

It verifies:

  • Working hardware, power supply, clock, uC is working.
  • Whole programming environment works. Compiler, makefile, interface to programmer, etc.
  • Programming hardware works, cabling is ok.

My brother’s solution for ski shoe dryer: buy 4 hairdryers and connect them in serie.

In our first product (Eprom programmer ‘Piccolo’ - I found it here: designed in 1988 I have used NE555 as a step-up DCDC converter controller. I know two ways of using it that way:

  • use reset (pin 4) to break pulse (or pulses) when voltage reach limit,
  • drive the internal resistor divider (pin 5) to change pulse fill factor.

Here (Poland) it were times when we had hard access to modern electronic elements, and its data (no www) and also element prices were very, very important.

In previous century we used standard LED existing in our devices to send the device type and serial number (not noticable by human). The idea was to be easy able to get that identification from already installed devices (like RFID reader) without need to get access to their wires. But even we had done readers for it (connected to RS232 PC socket, and powered from signal lines of that socket) we practically never used it.

:slight_smile: I was wondering about that but perhaps some microcontrollers are very cheap.

I will proceed to give you a hard time (if I can): Programming? compiler? Interface? What are those? Seriously though I think the question is whether to use a microcontroller for the sole purpose of blinking an LED. Adding that function to a device which is used for other purposes seems to make more sense, although my experience with Visual Basic 10 years ago tells me that I am not a programmer.

Recently, any time I have thought about using a 555, I was able to do better with a single or dual op amp or comparator. That is not ruling out all possible 555 applications though. A basic comparator or op amp oscillator is a design I learned as an applications engineer in about 1975. It is very stable.

Hi Piotr: I cannot confirm that they are available in Poland but I think that I would just buy the shoe dryer instead of 4 hair dryers.

I think everything is available. Now I see the cheapest ($4) hair dryer having 1kW. So 4 in serie have in total 250W. I looked in parameters of two (first I found) shoe dryer - they have 10, and 12W (I understand for 2 shoes) so 24W for 4 shoes. I’m not sure (was more then 10 years ago) but probably my brother had such shoe-dryer but said it is not effective and they don’t wont to have the ski shoes all the time wet so he found the simple and not expensive solution.

Hi, Piotr

This is sort of humorous. I hope that your brother has not burned his ski shoes “to a crisp” or burned his house down. I have only seen shoe dryers on the internet and never “in person”. It sounds like your brother was in a hurry to dry his shoes (maybe 30 minutes?) while my intent is an overnight dry and the commercial devices might require a few hours. I built a heated stool for use in my cold attic lab, and I can select heat levels of 20 or 40 or 60 watts. This design was only an “educated guess”. But in fact the 40W level is about best for steady-state “butt warming” and I am guessing that similar power levels might work for a boot dryer.

Getting 1/4 the power with 4 dryers in series would work if the dryers were simple linear resistors, but I think those heaters probably have resistance which has a positive temperature coefficient. Also I guess the fan motors are probably connected in series with the heaters, so do the 1/4 power calculation may or may not be close.

Four hair driers in series sounds a bit rough.
Will the motors now spin fast enough to push enough air through the system without all the plastic melting into a big blob?
What about a thermostat so not only plastic boots but leather shoes can be dried?
Perhaps a humidity sensor to detect when the shoes are “cooked”. It could be used to switch off the heaters, or, drop them to “trickle” heat so shoes will always be warm and ready for use.
And some nice comforting red LEDs.
Designs could keep everyone happy: op amps, 555s, or processors.

A good pandemic exercise…just to bring this thread back on topic :grinning: