Hakko FX-888D

In August 2021 I bought a Hakko FX-888D soldering station. Hakko has been active in this area for decades and the products are considered to be of high quality and durable. The operation takes getting used to, but the set temperature is reached very quickly after switching on and also kept well under load.

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In memory of Clive Sinclair

On September 16, 2021 Clive Sinclair died at the age of 81.

Sinclair was known for computers like the ZX80, ZX81, ZX Spectrum und QL (“quantum leap”). Especially the ZX81 and ZX Spectrum were very successful systems. In adition in 1972 he also launched the pocket calculator “Sinclair Executive” which was much smaller than other calculators at that time. In 1983 the “TV80” was launced – a very compact television using a picture tube which displayed the picture to the side whereby the device could be built very flat overall for the conditions at the time.

One invention which was not that successful was the electric vehicle “C5” from 1985 where only 17000 copies got produced for 8 months. Also the digital wrist watch “Black Watch” from 1975 was mostly a disaster – much too short battery life, the danger of destroying the electronics with static charge and inaccurate time which was depending on the current temperature.

Despite the failures, Clive Sinclair’s impact on creating affordable computers for end users should not be underestimated. The ZX81 was revolutionary back then – a personal computer at a price virtually anyone could afford. The ZX Spectrum later became a fixture in the home computer market of that time, alongside the devices from Commodore and Atari.

Shift registers

If you work with microcontrollers like the ATmega328 (Arduino Uno) or ESP8266 (Wemos D1 mini) and want to control many lines at the same time, it can become a problem that there are not enough outputs are available.

One solution are shift registers. More about this in my article about the 74HC595.

Fast SSD with NVMe

NVMe is the abbreviation for “Non Volatile Memory Express” and describes a standard for connecting SSDs via PCI Express. With SATA the speed is limited to 600 MB/s. In addition, AHCI (Advanced Host Controller Interface) used by SATA was primarily developed for hard drives and limits the possible I/O operations per second (IOPS). With NVMe both have been improved – PCI Express enables significantly higher transfer rates of up to 32 GBit/s or 4 GB/s via PCIe 4x and more than 500000 IOPS.

After one of the SSDs in my “retro PC” started reporting checksum errors I installed an NVMe drive with a PCIe adapter card for M.2 as a replacement.

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First Covid 19 vaccination

Two days ago I received my first Covid-19 vaccination in a vaccination center in Berlin. I got Comirnaty from BioNTech as a vaccine. The whole process was organized very professionally – I came straight to the admission without queuing and it took a total of maybe 20 minutes until the actual vaccination. After that I had to stay in the waiting area for 15 minutes so one can react immediately to any severe vaccination reactions – which I didn’t have.

During the first few hours after the vaccination, I got a slight headache that lasted until the next day. I was also quite exhausted so I went to bed in the afternoon. The the left arm where I got the injection was a bit painful until the next day, but only when touched directly. Overall, however, the side effects were quite bearable and today, on the third day, the headache is completely gone and I can feel the pain on my left arm only very slightly and expect this to go away completely tomorrow as well.

My little “electronics lab”

Some time ago I rediscovered my interest in electronics and recently done my first project. This project was created at the table where my PC is. However, this is not an ideal place to solder circuit boards or create designs with breadboards – I have to take the necessary parts and tools such as soldering iron, multimeter, etc. out of the drawer and then tidy up again afterwards.

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HDSP-211x for Raspberry Pi

On the project page about using LED matrix displays of the type HDSP-212x, I also showed an example setup with a Raspberry Pi. Now that I still have some of these displays, I would like to use them to build a real device in its own case.

Soldering the whole thing by hand on a perfboard would theoretically be possible, but is prone to errors and in the end you have only one copy. Nowadays there is a better solution for this: you design a circuit board with a program like KiCad and have it produced as a small series for comparatively little money.

My first draft for a board on which you can put four HDSP-211x next to each other already looks quite promising:

At AISLER, the production of three copies would cost around EUR 25 and would be ready in about a week. But before I actually do this, I’ll have to check the circuit diagram again and check whether adjustments are required for the power supply, since four modules together can have a power consumption of more than 1.6 A.

Revision 2

After taking a closer look at KiCad, I created a revised revision 2 of the layout:

  • The total size of the board is a bit smaller.
  • The mounting holes are now inserted as footprints and without soldier mask.