In writing the previous six articles about designing and building a digital clock, I found some software bugs and some improvements that could be made to the hardware design. I also found that the act of wiring it up by soldering bodge wires to a protoboard was a royal pain in the backside.
I couldn’t leave it there, it felt incomplete.
So, I looked and found I could order small batches of custom Printed Circuit Boards (PCBs), some of these companies even made them in the US. It did require learning new software as I had to provide them with the design. I tried out two – Design Spark and KiCAD. I already had KiCAD from when I drew up the schematic for an earlier article, and picked up the free version od Design Spark to try it out. The initial learning curve to get started is a bit steep, so I bounced back and forth between programs trying to get over that first hurdle. Once I got moving, the learning curve levelled out and became easier to get better. I ended up with KiCAD mostly by luck of the draw as I got a footprint on the diagram there first.
A footprint in PCB design software terms is the layout on the board for a component’s connectors properly placed so that said component can be attached later. It often also contains some silkscreen drawings and text. But I’m getting ahead of myself. To talk about designing a PCB, we need to talk about the structure of a PCB.
Your most absolute basic PCB has the board and a layer of copper traces. These traces are where the electricity goes. However, this style of single-sided board is an antique. It has a lot of shortcomings, not the least of which is the difficulty in laying out circuits where the traces have to cross each other without shorting. Also, exposed traces are easily damaged, especially by corrosion. The answer the first problem, most modern circuit boards have either two or four copper layers separated by insulating board, and the outside has a solder mask covering most of it. The solder mask shields the traces and is a material the solder doesn’t stick to. It is essential in preventing short circuits and forstalling corrosion. And to top it all off, there’s an outermost layer where ink is printed on the board. This is the silkscreen, named for the printing technique used to apply it. The silkscreen exists entirely to provide information to the human looking at the board. Most often it will contain information about the components you’re supposed to have on there and how to hook them up.
I designed boards with two copper layers, because it was the default and I could make it work. I could have made it with fewer vias if I used four layers, but that would also be more expensive. What is a via? A via is a hole through the board connecting the copper layers to each other. Sometimes they are places for soldering in components, sometimes they just move the trace to the other side of the board. Speaking of soldering on components, there are two general types – through-hole and surface mount. These names are self-descriptive. Through hole is the older style where the leads from the component are poked through holes in the board to provide more hold to solder them in place. These tend to be bigger and easier to solder by hand. Surface mount components solder on to exposed pads on the surface of the board. They can get much smaller and when you have robots attaching them can get downright microscopic. Surface mount components are more difficult to work with, but allow for more miniturized final devices.
Being a rank ameteur, I use mostly through hole components. I say mostly, because my first PCB was a simple deisgn to convert a surface mount component to a through hole. What am I talking about? This thing:
A Learning Experience
You see, in looking forward to future projects, I found that the software limitations of the chips I’d been using were a problem. But the MSP430 series chips with more resources were all surface mounts. I identified a model which had a launchpad and designed a board to connect the pins to pin headers. This solves so many logicstical issues with prototyping and programming the chip. Rather than affixing the chip to a board and having it stuck there, I can make a pluggable module that can be moved from breadboard to launchpad, to final device. Yes, it’s bigger, but it’ll be easier for those future projects. I also left a spot for a clock crystal just in case I need it.
Now that I’ve learned how to design PCBs in general, I can put together the clock in particular. The built-in footprint library that KiCAD comes with doesn’t have… well, most of what I need, especially in the Integrated Circuit category. Thankfully, the comapny I’ve been buying a lot of my components from (DigiKey) often has footprint models to download for the components they sell. Win! Unfortunately, they did not have one for the display. Sad! So, I had to break out my calipers and start measuring the leads on the display to lay out the holes. Thankfully, they had masurements that could be done in multiples of 0.1″ between centers of the pins. Being a standard spacing, the measuring tools and grid in KiCAD could easily lay out vias in the correct pattern.
Now for the real challenges.
Because I’m paying for someone to print me up circuit boards, I have to be mindful of the cost. This cost is calculated by the size and complexity of the board. Two-layer is the simplest, and thus cheapest (since single-layer isn’t used regularly), so the question becomes one of fitting into a smaller footprint. After laying down the basic elements I decided to stick with a 3.25″x2.25″ footprint. This ran a smidge over $10 with my chosen provider (Made in the USA). I could have squeezed a slightly smaller footprint out of it with some shenanigans and moving some components to the other side of the board. But I decided it was worth it to make it easy on myself later. I spent a lot of time tweaking the layout, but this is what I came up with:
It is a bit hard to read at first glance, what with the layers all stacked up.
If you notice, I changed the design of the hardware. The switch to control whether or not the user can change the time is now completely separated from the software, it turns on or off the power to the buttons instead. I also added a power regulator with its recommended regulating capacitors between the battery connector in the upper right and the rest of the circuit. I’ve also connected the previously unused pin 15 on the SN74HC595 up to the lower right dot on the display. Lastly, I’ve added a switch to pin 9 on the microprocessor. What I plan to do is update the software to show whether it’s AM or PM on the display, and turn off the display without disabling the clock.
I did forget to label the positive and negative pins on the battery connector. The only saving grace is that I set it up to work with the battery packs I already own so I won’t get it backwards if I just plug the keyed connector in. Oh well, it’s not a deal breaker.
Next, I’ll have to update the code to incorporate these updates, solder up a prototype, and then design a case for the finished clock.
Oh, did I mention that I want to 3D print a case so that it looks and acts like a real device? Well, I want to. Then, this project will be complete.
You’ve gone past my experience building circuits. After I’ve gotten something breadboarded I’ve always transferred it more or less exactly to a prototype board like this:
https://www.adafruit.com/product/1609
A lot of the stuff I’ve done is for the Raspberry Pi so I’ve used a board like this:
https://www.adafruit.com/product/2310
I have a lot of protoboards, but don’t like working with them. Mostly its the trouble I had finding jumper/bodge wires that worked well. (I have now, but it took a number of tries)
Some years ago a friend gave me a four foot long section of telephone cable containing maybe 50 twisted pairs. Ever since then when I need thin hookup wire I pull out pieces of the colors I want and cut and strip. The only downside is that sometimes the insulation retracts a little when soldering to the pad. The millimeter or two of exposed copper is unaesthetic.
Soon you’ll be able to build a robot to replace your porch light.
Why would I do that?
Robots are more useful when it can move.
Won’t somebody think of the orphans?
Besides Chris Hanson?
You’re right, we need to outfit the robot with net launchers to catch escaping orphans.
Or outfit the orphans with networked robot launchers so there’s no ladder needed….
I knew it was a mistake to do the dive into the C code. I’ve bored people away from the series.
I’m in a state of trepidant vigilance for the articles on auto-turrets.
After all, a guy has to be able to defend himself against the coming zombie apocalypse.
I first read that as “Audio Turrets”? and sonic anti-zombie defenses seem interesting.
More likely folks are working. It is during the work hours, after all. I have time to skim and briefly snark, but that’s about it. I expect that’s not atypical.
But that’s less funny.
You got 93 comments now. Far from it. Good going!
NA from the ded-thred Russia moving to NATO = good?
I’m curious, do you think you are quoting me, or reading my mind?
Perhaps you are the lovechild of The Hyperbole and Victoria Nuland?
I don’t like to drag arguments across threads, but yes. That is exactly what you’re saying. “Russia can’t tolerate having NATO on its border so it’s reasonable for it to conquer territory so its new border is adjacent to NATO countries and anyone who disagrees with this is bad.”
More like “If Russia is going to be forced to share a border with presumably hostile NATO countries, putting a few hundred miles of buffer territory between NATO and the old Russian border might be prudent.”
but yes
Well, that’s just remarkably stupid. You might as well be a denizen of DU with that kind of answer, and outlook. What put such a bug up your ass?
If you’re going to be a twat by continuing a fight past its natural end point, consider that you may be being a twat in other situations?
For example, ignoring context makes you a twat. You made the following statement in context of Russia’s invasion of Ukraine:
So yes, you are in fact justifying Russia’s invasion of UKR with the excuse of “Russia (not just Putin) shouldn’t stand NATO moving towards them.” This is EXACTLY the same thing as NATO moving to Russia = Bad.
But then by accepting the concept that Russia will/can/should stand having NATO on its borders as long as it’s doing the border moving, you are saying Russia moving to NATO = good.
Don’t blame me for what you write.
Just curious, but does Russia (not Putin) have legitimate national interests or not? It certainly would seem you think it does not. That’s the essence of the Nuland construct – it does not, it may only do what we decide. I get arrogance, and everyone is projecting it – myself included.
If the US and Ukraine both knew that Ukraine in NATO was a redline that they would not tolerate and fucked around anyway, I’d simply say that it’s hard to absolve them of blame for the current war.
The US and Ukraine both knew.
Sitting here and trying to moralize the foreign policies of nations is just kind of naive. Russia is doing nothing different than any other country would put in this situation with the strength to respond.
If the US and Ukraine both knew that Ukraine in NATO was a redline that they would not tolerate and fucked around anyway, I’d simply say that it’s hard to absolve them of blame for the current war.
The US and Ukraine both knew.
THIS.
Russia drew a bright red line involving the Ukraine entering NATO. The US and the West raised a middle finger and are in the middle of stepping over that line. Russia is working to prevent that step, and NA is crying foul over it.
This. Morals and laws have nothing to do with it.
I maintain that if China or Russia were pulling coups and building bases in Mexico, the First Armored Division would be rolling into Mexico City.
We knew and kept pushing. The neo-con cult was founded by Trotskyists still trying to settle old grudges.
I’ve bored people away from the series.
This is incredibly impressive. Even if I don’t grasp the details, the process is admirable.
I admire your interests, particularly the range – it’s like you’re fulfilling the Heinlein quote of what a civilized man should be capable of, and then some. The details tend to lose me, then again, I felt the same about the forging.
Could you please build me a digital alarm clock with large blue LED numbers that resets for the next day automatically when I turn off the alarm but lets me turn it off for the weekend and back on on Sunday night without having to scroll through hour setting, then minutes setting, then alarm on/off, then alarm volume high/low for TWO different alarm settings, the second of which I never use? ‘Cause that would be just great!
I have a cheap alarm clock from Amazon that does all that. When you set the alarm, you can pick every day, week days, or weekends.
https://a.co/d/8ySSHox
/looks at the alarm function on my phone
I’ve got an old LED (black lettering, but can be backlit blue) that can do most of that, but it’s been unplugged for a while as it had a voice activated feature (so you could turn on sleep sounds, or turn off the alarm by talking to it) that kept getting activated by random sounds.
I’m impressed you have stuck with this rabbit hole for so long. You’ll be soldering the components onto the PCB by hand? What soldering iron do you have?
I can’t speak for UCS but my soldering iron is a Weller WES50. It’s no longer in production. The latest equivalent is the WE1010NA:
https://www.amazon.com/Weller-Digital-Soldering-Station-WE1010NA/dp/B077JDGY1J
Mine has a dial for temperature instead of the new-fangled digital control.
In college I made my own thermostat I found in a magazine article. Just a wooden box, part of an extension cord, a dimmer switch, wall outlet, and a fuse holder/fuse. Fun little project and it worked great.
My regular Iron is This guy.
The hot air system is This guy.
I also have a trash $15 iron that came with the build your own Arduino kit.
Most of the accessories are not attached to either because I don’t need them and they clutter up the space.
As for sticking to the rabbit whole, I just wrote up parts 10 and 11, they’ve been scheduled (with someone else’s article in between for variet), and I’m waiting on some more circuit boards to go into part 12 because – surprise surprise, it’s still got flaws.
Speaking of soldering…
Hasn’t somebody developed a conductive “glue” to cold bond electrical components yet?
Why not?
https://www.amazon.com/Sciplus-Electrically-Conductive-Soldering-Wire/dp/B000Z9H7ZW
When I worked at the cop car shop, a commercial version of Super Glue was used just for that in specific non-vibrating areas. Solder works so much better, that unless you are looking at a very specific set of circumstances, it is not as good of a solution.
Because solder is electrical glue. And there are a lot of manufacturing processes already built around its properties.
They have, but they are inferior for high power applications.
https://www.epotek.com/products/electrically-conductive-epoxies/
By the way, they still need to be cured at temperature. Typically they are screen printed like solder paste, but cured instead of reflowed.
https://www.epotek.com/wp-content/uploads/2021/01/PCBGuide.pdf see page 13.
Robots are more useful when it can move.
I meant a robot electrician, not a robot chandelier.
Wire wrap for the win!!
I have a project that should be wire wrapped. I still have some simple hand wrappers and spools of wire from 40 years ago. Where my memory fails is the location of my wire wrap IC sockets, and I’d have to get WW headers for non-IC components. Components are somewhat different now than they were then.
I keep telling myself I should get a speeduino or a microsquirt to play with, but I just don’t seem to be as interested in reinventing the wheel as I used to be.
Judge Napolitano talks to Scott Ritter about having his passport seized at the airport. Napolitano was supposed to go to a conference in St. Petersburg also. Ritter warned him off not to go ahead of time.
https://www.youtube.com/live/lOsW84wYdzg
Once again you’ve jarred my memory of my college days. We did make our own printed circuit boards. Designed everything on a computer, printed out the design on a sheet of plastic, put that over a PCB blank, exposed that to a UV light, then used a chemical process to remove everything but the traces. The process was imprecise and the traces had to be somewhat wide, and there were still broken traces to deal with. But it was fun to do the whole thing by hand.
On the other hand, $10 would have been an absolute bargain 30 years ago. Wow.
Twenty-five years ago, in a production setting, it was still imprecise. We made flexible circuit boards for Jeep transmissions. My job was to test every circuit board on a bed of nails to determine pass or fail. We were happy with a 50% scrap rate.
Aw man, stereo-lithography was the best part of my freshman electronics engineering final project…
Question: Gunsmith called, said he has my gun working, but the reset is no longer audible. Is that a sign that he hasn’t actually fixed the problem? He said the problem was the disco needed material removed.
I would say that that is a sign he hasn’t really fixed the problem.
I’m wondering what the mechanism is that makes the *click* on a trigger reset anyway.
So many things I need to learn about these little machines.
When is the BTU reflow oven coming? Alternatively you could make one out of an old toaster oven.
https://youtu.be/k9xzGO0SVg0
Redlettermedia took some shots at guys like Nerdrotic and The Drinker for their supposedly clickbait videos. WIthout ever having watched any of their videos or actually comprehending their arguments.
I’ve said for a while Redlettermedia want to be fence sitters. They are lefties who are kind of getting passed by. Their channel is barely growing at this stage because they refuse to comment on the biggest issues facing the movie industry. They danced around quality and the reasons for its decline so much in their Death Of The Movie Theater video it was comical.
You can’t talk about the decline of quality without talking about DEI. Both in front and behind the camera, you aren’t getting the best in Hollywood. It is no longer a meritocracy, if it ever was. It’s certainly worse. It’s a toxic swamp of DEI and nepotism.
RLM are fence sitters no doubt who reached their peak with the Mr. Plinkett Star Wars skewerings. That being said, that whole genre including Nerdrotic and Drinker are becoming passe unfortunately. When everything released sucks it’s less fun to watch.
Can you become passe when exactly what you said was happening and would happen is happening?
They aren’t responsible for everything sucking. They just called it. And when they like something, they say they like something. Like Furiosa – most of them liked it just like RLM, but there’s RLM using their thumbnails to mock the notion of clickbait videos on female leads sucking.
Godzilla Minus One came out for digital purchase (and probably streaming) from what I can tell this past week. That’s at least something that didn’t suck.
(Seriously — yes, it is a Godzilla movie… no, I’m not that into kaiju…. but it is a really good movie all the same!)
It’s free on Netflix.
Everything Sucks!
Can you become passe when exactly what you said was happening and would happen is happening?
When you’re constantly talking about Disney and Amazon PANICKING and people start realizing that literally nothing is changing.
I used to watch both on the regular, but once I accepted that the franchises I cared about were dead and cold, I lost interest in the critiques.
Pretty much Trashy, it used to keep my interest seeing how they were going to pull these various franchises out of the fire before they burned up. Now they’re long dead and it’s just kind of depressing.
I always got the impression they were UW-Madison types.
They are. They aren’t woke, but they are left leaning individuals who can’t see the forest for the tree when it comes to the culture war. They wouldn’t want to side with icky people now that this is all political.
The Plunkett reviews of the Star Wars prequels were productions in their own right. Mike is an insightful reviewer, and seems to have a good idea how stories are supposed to work.
But, I agree that they’ve tried too hard to remain apolitical, and I expect they have seen some of the rot in Hollywood. They are friends with Macaulay Caulkin, and I would be surprised if he hasn’t shared with them stories about how he was treated as a kid.
*Plinkett
Pretty impressive, Unciv.
I just do not have the hands for this kind of work.
Hat (and monocle) tip to the rest of the Glibertariat! Hope everyone is well.
I’m always well. I’m First.
Touche, Bro.
How do you feel about the courts smacking down covid mandates in the military years late?
I’ve still got 4 military cases ongoing, so I’m delighted whenever I see a good result. More ammo/precedent with which to bludgeon the judge.
3 are in the Court of Federal Claims and we’re making good progress there. One is hung up in N.D. Texas on a recalcitrant judge.
I’ve got two others in district courts on behalf of a (non-military) pilot who got fired for refusal.
No lack of work, that’s for sure.
This part is all mouse clicks, it’s next week when the soldering begins where some manual dexterity gets involved.
I always wondered how those boards were “put together”, so this is pretty cool.
I’m gonna go back and catch up on this series.
Good to see you around here Ozy! I was up in your neck of the woods a couple months back. I’ll have to get up there again soon, it a nice town!
Thanks, trshy!
I hope you’re talking about KC ‘cuz that’s where I am – not too far from Ms. Mojeaux.
BBQ is plentiful and excellent, plenty of places to get out and around.
I’m diggin’ KS.
If anyone is ever around KC and looking for a way to kill some time, happy to oblige!
Oh, Article 8 is “Autopsy of a Failure”
Bonus points for anyone who can spot errors highlighted without using WordPress powers to look at that article.
I don’t think the You’re not my supervisor! has ever seemed more appropriate… 🙂
as long as the failures are Hardware related I might stand a chance.
Found the Shadowgate documentary online. It’s worth watching, and the claims made by the intel contractors are true, in my opinion. It mysteriously and rapidly taken off YouTube in 2020.
https://archive.org/details/shadow-gate
Some good political content in a similar vein from catastrophic climate change skeptic Tony Heller:
https://www.youtube.com/watch?v=ieMO5JKCgcI
Oh god, waiting at the doc’s office and they have the adult contemporary freaking blasting. If I had to work here I’d go nuts (or quit, probably quit).
You could get some good drugs at the doctors office to help you cope.
https://www.youtube.com/watch?v=MvoCxOv6zL0
It sounds more like AI generated Kenny G with lots and lots of soprano saxes screeching away. Literal Hell on earth.
I confess I’m surprised I couldn’t find a Muzak style cover of Head Like a Hole on YouTube. Of course, we should be up to Muzak covers of early 2010 songs now, right? Wouldn’t know what abomination that would spawn….
Not Muzak, but a weirdo cover by Devo. I like it.
https://youtu.be/W2M9jaulods
They did not play that at Punk Rock Bowling, they did play Whip It, which made the girlfriend happy. Of course, she was chatting with people, and learned the TRUE AND ABSOLUTE meaning of Whip It from someone… it’s obviously a pro-Carter song that’s anti-inflation, and there are no other meanings behind it.
HA!! Yes it was. No other meanings possible.
Oops
Toyota is recalling approximately 102,000 vehicles for potential engine failure, with the recall affecting both the Toyota Tundra and Lexus LX from the 2022 and 2023 model years. The recall is only for the purely gas-powered models and does not affect the hybrid powertrains. Detritus in the engine can lead to a loss of power for the engine, according to documents filed with the National Highway Traffic Safety Administration (NHTSA).
The recall affects vehicles equipped with the V35A engine, a twin-turbocharged 3.4-liter V-6 that is offered with varying power outputs across the Tundra and LX lineups. The NHTSA documents explain that engine machining debris might not have been removed from the engine during the production process.
I would say if your motor hasn’t eaten itself by now you’re probably in the clear. I assume those blocks are cleaned by some sort of automated process. I wonder what went wrong.
Smurf themed?
Futuristic/sci-fi themed?
A hand wearing a glove?
Top hat with the clock display inside the monocle of course!
I have not yet decided – I need to make sure the system is complete.
Surprise of surprises, I’ve not ironed out everything.
Build your own out of acrylic/plexiglass.
That’s another whole set of articles. You can etch, polish, cut…bust out that dremel and torch! Illuminate with LEDS…
Also, spray painting the back of plexi gives a great looking finish on the front.
But, I have a 3D printer…
No Pepsi!
Dr. Pepper!
https://finance.yahoo.com/news/dr-pepper-just-passed-pepsi-182921542.html
One of us! One of us! One of us!
https://www.youtube.com/watch?v=gQPN3UKQM-U
Werewolves prefer Dr. Pepper.
Soda makes you fat.
I thought that was garlic bread.
I presume that there is always the need for “content” so I’m putting some stuff into the submissions pile that I wrote on my personal ‘stack. I think others might find it readable (enough).
It’s a series about my personal experiences with aviation mishaps (i.e. crashes). I’ll drop them all in the slush pile for Swissy or someone else to slot in if/when there’s a need.
The hungry maw of Swiss thanks you.
It’s a series about my personal experiences with aviation mishaps (i.e. crashes).
Atypical landings.
Unanticipated deplaning events.
Traumatic deceleration occasions.
Was the reply button always on the far right side where you naturally scroll? Getting tired of opening up the comment box.
https://bearingarms.com/camedwards/2024/06/04/biden-defense-attorney-throws-hallie-biden-under-the-bus-n1225132
Hunter, the smartest man that Gropey Joe knows!
Those defense “arguments” suck.
That website sucks.