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DIY 4G LTE Antenna - Simple Folded Dipole

Due to an unfortunate event related to the coronavirus pandemic, I have been repatriated back to the Philippines from Singapore. I have now temporarily relocated to a remote rural town in Cebu where there is no broadband service lines from any provider. Because I still have to work, I needed a decent internet connection. This sounds so simple but it's actually not. This past week, I have called all the internet service providers in the Philippines and none of them considers my current address as within serviceable area. I realised that my only option is to go through a pre-paid 4G LTE connection. But the 4G service is very poor that I could hardly get 1 or 2 bars of signal on your phone on the street. Internet speed at this signal level is less than 1Mbps. It feels like the 90s. It's obviously not enough to start a video conference for work. Imagine how frustrating this is for someone who lived in Singapore for the past 9 years. I had a 1Gbps fiber optics line in Singapore.


Bui…
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Architecting Systems Like A Rock Band

In Software, orchestration often means control, synchronization, mediation and scheduling of decoupled application services in order to fulfill groups of tasks as part of a business processes. In highly distributed systems, orchestrating could be a nightmare to develop and maintain. If not designed carefully, it can lead to a scenario where the orchestrator becomes the bottle neck to future architecture changes. In traditional SOA, the orchestrator is often called the service bus or enterprise service bus. Even Micro-services architecture has an orchestrator. It hides behind the name "Gateway" and "Control Plane".
In an Orchestra, if the conductor leaves the orchestra in the middle of a symphony, chaos could occur eventually. The percussion section could become out-of-sync with the woodwinds and the brass section overtime. This is because each musician and each section rely heavily on a set of rules and patterns in the sheet music and of the tempo and the instructio…

DIY 3D-Printed Electronic Drumkit : Update

After playing my 3d printed drum-kitfor a while, I started feeling a bit unsatisfied with some of the parts. I figured I needed a snare drum with a rim shot and a bigger pad area. Also, the hi-hats do not feel like a real hi-hat as it doesn't physically open or close. Very often, I always miss the tempo when opening and closing the hi-hats with just a foot switch. I also figured I would need a new Midi Trigger interface because I cannot just attach those new pads to my existing cheap Medeli drum module. I also expect the look would be a lot cooler with bigger cymbal pads. So, here's what I did.

The Snare

I bought a Millennium Mesh Pad snare just before they discontinued the product Millenium PD-1012 12" Mesh Head Pad for only 66EUR. It's a cheap mesh pad snare. But I did not mind, because I was only interested in the shell. I replaced the head with a Roland V-Drum Powerply (it's a 3-ply). It's quite expensive but is worth it. I got all of them from Thomann onlin…

Jieming's Router Anomaly

Last night, while randomly watching my router's activities, I found out that it has an active connection to some IP address owned by Amazon and hosted in New York. While trying to do curl request to the server's port 80, it returned a website and when I opened it in browser I was quite surprised because it is a ASUS router's web interface (ASUS RT-AC5300). The weird thing is that I was able to login automatically without being prompted with username and password. And also I am able to see everything, including the local devices connected to the router and administration settings. I tried changing something but it doesn't seem to persist the configuration change. So I took a look at the site's client scripts and it's kind of weird. By the look of the Javascript code, the apply button will never work at all. It looks like it was deliberately done.

I tried digging deeper and see which of  my processes  are connecting to this server and it say's com.apple. It me…

DIY 3D-Printed Electronic Drum Kit

Source files available in GitHub: https://github.com/rossbrigoli/Tambol

Inspired by a 3D printed drum pad by Frank Piesik, I decided to make my own 3D printed drum pads. I have an old cheap Medeli DD402 electronic drum kit lying around and not used for quite a while because of some faulty piezo-electric sensors that I was too lazy to replace. So instead of fixing the those faulty noisy rubber drumpads, I thought to replace it with a 3D-printed mesh head drum trigger.

I have made up my mind from the beginning that I will replace every rubber drum pad of my Medeli drum kit with a 3D printed one. This meant that I had to print 4 drum pads and that I have 4 chances/opportunities of improving the design. I did it in a Agile/ Iterative way and also in a modular design so that I do not have to re-print the whole thing if I decide to change the design in the following iterations. I only need to re-print the specific parts that was affected by the new design.

Iteration 1

I took the design of …

Building a 3D Printer and My 3D Printing Adventure

I can't believe it was almost 10 years ago since I first heard about the RepRap project. It is an open source hardware project aims at building a self-replicating 3D printer. The concept of open source mechanical hardware was new at the time. I badly wanted to have one but I could not afford it. The kit was so expensive at the time. If I remember it right, the kit was being sold for 4,000 USD. It was way beyond my ability to afford. It's the price of a second hand car. After all, I was making only a few thousands pesos (Php) at the time.

Two weeks ago, while I was checking for the status of my online purchases at AliExpress, an advertisement came up about a 3D printer called Delta. It caught my attention so I clicked the ad which leads me to a product on sale about a something called Kossel Delta 3D printer. It looks familiar, it looks like a RepRap design but it's different. There is no Cartesian rods, instead, it has a triangular frame wherein three stepper motors are dr…