Posts

UV Laser PCB Engraving

Image
One of the problems I often encountered was ... the iteration time of PCB manufacturing. I don't design complex circuits, I mostly design circuits for sensors I need. For instance, a tiny circuit for a single Hall Effect sensor... pretty much one single 8 leads Hall Effect IC plus a couple of capacitors, and pull up resisters, at size like 0.5"x0.5". They could be CNC milled.... I achieved CNC milling of such PCBs 20 years ago.... but they are tricky and finicky.... backlash of your CNC router and the diameter of the carbide end mill would be larger than the trace width means you have to tightly control all parameters. Any mistake, and it will cost you USD $20 for a broken tungsten carbide end mill. Board houses.... take minimal 2 weeks. Any design mistake, and as a hobby circuit designer, I make a lot of stupid mistakes even for trivial circuits. Each costs not just money, also costs another 2 to 3 weeks of wait time. I tried many many different ways of getting around th...
Post a Comment
Read more

PCSensor's Crummy Foot Switch Swapped Out

Image
Don't get me wrong, I like the electronics! What is it? It's basically an USB composite device, a mouse, keyboard, and joystick 3-in-1 USB composite device. You get to download a program, ElfKey, and graphically program the foot switch to either output a key, mouse button, or a joystick button, or record a macro. Then, you download the "programming" to the USB device. The MCU is most likely located in the oversized USB plug, completely embedded inside the plug. Not that it can prevent me from opening it up, but I am too lazy to even bother with this trivial thing. The one shown below is an upgraded version with so the called electro-optical switch. It's simply a pair of IR emitter/receiver with a couple of passive elements to 1. drive the IR emitter using a simple resistor as a current source, and a pull down resistor, and 2. a diode, for cascading up to 3 such PCBs (3 pedal set), using just 4 wires instead of 5. The later part I really do not like. I mean, all yo...
Post a Comment
Read more

AVRPit Part 2 (modular design)

Image
  In the last AVRPit post, I "claimed" modular design.... but didn't do a good explanation nor demonstration on modular design. Here, in this post I will attempt to demonstrate what I meant by modular design. In the next two screenshots, you will see that the basic frame design is very simple. It's built on top of a horizontal rectangular frame built with 1515 extrusion, sitting on two 6x6" wood posts with caster wheels mounted under the posts. Everything else are mounted on top of this frame, including a sliding car seat (not shown). In fact, the frame is built around the car seat. I chose a car seat that is narrow enough to fit inside an F-16 pit (most car seats are too wide), and then design the frame's width to fit the rail for the seat. Up front mounted a plywood platform and two "gates" built with 1515 extrusion. The wooden platform is designed for rudder pedals, so the rear half is covered with thin aluminum sheet for sliding of the the pilot...
Post a Comment
Read more

Hempstick 2.0 Delay... sort of

I recently bumped into a problem with Hempstick 2.0 development, and have to put in a "sort of" delay. Shouldn't affect the final result timeline too much... For those who did not read the previous post about the next gen Hempstick, it's a Linux-based panel controller instead of using RPi Pico kind of embedded processor (I might still write that one, if I find the latency of Linux-based Hempstick too slow, and let it handle the low latency "hungry" stick/throttle/rudder, and the 2.0 handles higher latency panels. So, whether there will be Hempstick Pico depends on the results I get from Hempstick 2.0.). This would be a fleet of RPi Zero 2Ws, each has 4 cores, 1GHz, and as much as disk space you want on the SD Cards. It could also be RPi 5 with an NVME drive (but I am not building a Linux distro for RPi5, as there is no point, just use a Ubuntu distro., instead I will build a bunch of Debian .deb files that you can just download and run "apt install *.de...
Post a Comment
Read more

Clever Little 3D-printed Clamps for 8020 Aluminum Extrusion

Image
Nothing much. Just showing off some fringe benefits of building a "pit" with 8020 (or clones) extrusion are. What everybody thought first of using these 8020 extrusion is the benefit of quick construction. It's easy to cut, and can be quickly framed using store bought connectors, and screws. But the other well-known benefit is easy to hang stuff to the frame, all kinds of stuff. The first picture below shows a basic hollowed 1x1" block. This could be used to "screw" in rails. I wouldn't put it to lock in two major structural load bearing frame, but for minor frames like left, right console rails for an F-16. It's plenty strong. Just don't put you ass on it. You basically slid in the "T-plug" from the end of the 10x10 rail, and then screw in the other one. The next picture shows a split basic block (filled in), and with bigger holes for holding cables. You press in 1/2" T-plug anywhere you want. put the cable on it. And you put in ...
Post a Comment
Read more

The Next Generation Hempstick Prototype

Image
  That is a screenshot of USB Probe on my iMac, showing the Hemptsick USB descriptor... 3 axes, 64 buttons. But it can contain whatever combo you want. It is a live USB device, a Raspberry Pi Zero 2W Linux device, costing USD $15 + a microSD card. It's a 4 core ARM64, 1GHz device. It's a full computer.  The deal, eventually, is... you download a .img file, that is a full Linux OS. Then, you burn it to a microSD card of your choice, with a program like Raspberry Pi Imager. Plug in the microSD card into a Raspberry Pi Zero 2W stick... boot up, and plug in the USB cable to the Zero 2W, and the other end to your gaming rig (iMac, in this test)... and it boots up and shows up on my iMac as a USB joystick. Inside the .img, there are the following, at the moment. a Custom compiled Linux Kernel, v.6.16.3 to be exact, with the RealTime feature turned on, a program, tentatively called hempstick-hid-import, a config file, tentatively called hempstick-hid.conf, a systemd unit file to auto...
Post a Comment
Read more

Ha, they fit!

Image
They fit. A real Left Aux Console was measured with a caliper and a few other hand tools and 3D modeled, years ago. This year, I acquired the real landing gear module. I didn't even know what those 3 holes were for... but I modeled them anyway. And today, I finally 3D printed it (with some extra excessive stiffening I am regretting now). Now, I know what those 3 holes are for. And they fit perfectly. I think I will just use the real landing gear module, and the real landing gear panel. Simply because I can. ;-)  
Post a Comment
Read more