Category Archives: miscellaneous and news

Here I post everything that doesn’t correspond to a specific category

HomeMatic smoke detector HM-SEC-SD quick repair

This time again a quick article on the subject of “Aging and Homematic Smart Home”. It’s about the following device: The Homematic smoke detector HM-SEC-SD, i.e. the older version of the smoke detector from eq3.

First of all: This article only shows how I put this device back into operation. Since it is a safety-relevant device, an acceptance test by a certified testing company would have to take place after the repair in order to be allowed to continue using it. So the contribution only provides what has become broken in the device.

So what is it about? The radio smoke detector HM-SEC-SD showed the following symptom during the monthly test (yes, you should press the test button once a month):

A short press on the button and there was no acoustic signal – instead the red signal LED flashes several times at approx. 0.5s intervals. Replacing the batteries does not change anything, the behavior remains the same. The radio module of the detector behaves normally. It can be reset and taught again. In this case, a look at the operating instructions (under point 9.2 on page 24)

– If only the LED starts to flash after pressing the button, the smoke detector is defective and must be replaced
So time to open the detector and take a look. My first suspicion fell on the detector chamber and that there is contamination here or that an animal has settled in the chamber …
Smoke detector opened

But after removing the lid of the detector chamber, no animal intruders were to be found. However, a strange pattern could be seen on the inside of the lid:

Streaks on the inside of the detector cover

These streaks, I thought at first, were created during the injection molding of the plastic component and must be like that. But on closer inspection and a “wipe” with your finger, they could be removed. In short, these streaks are dust particles. And when they are on the lid, then also in the entire measuring chamber. So blow it out with compressed air, put the cover back on and test it. -> same mistake as before. So again, put the lid down and take a closer look with a magnifying glass. The coarser dust, if you can speak of “rough”, was gone, but the surface of the photodiodes still had very fine and difficult to see streaks. So I cleaned the chamber and the diodes with a little alcohol on a cotton swab.

thorough cleaning required

Another function test showed success – better partial success. After pressing the test button, the piezo squeaked – but only very, very quietly – and by that I mean barely audible and the LED flashed nine times at an interval of one second. So actually the way it should be. Just way too quiet. So something had to be broken. So I examined the circuit starting with the piezo and quickly found what I was looking for. The piezo is controlled by a 40106, a 6-fold Schmitt trigger. In order to get enough electricity, three “Schmitts” are connected in parallel. The output was low-resistance, which is actually not allowed to be. So unsoldered the 40106 and measured it again. Between pin 1, 2 and 7 (input and output of the first Schmitt trigger and the VSS pin) there was a full short circuit. That means the IC is defective.

6times Schmitt trigger IC 40106

After the IC was exchanged, the smoke detector could finally “scream” again as usual.

Homematic actuator quick repair (dimming actuator RS485)

I have another small contribution to make on the subject of “Aging and Homematic Smart Home”. Many thanks to Fritz for the preparation and analysis.

As in the last post “Homematic actuator quick repair”, this time it is again about a device from the Smart Home series. It is the dimmer actuator with the designation “HMW-LC-Dim1L-DR”. This is a phase control dimmer actuator for incandescent lamps and low-voltage halogen lamps with conventional transformers. Many modern LED lamps can also be controlled with this dimmer. The actuator belongs to the “wired” series, which means that it is not connected to the CCU via the BidCos radio protocol, but via the RS485 bus. The actuator receives the power supply for data communication from a 24V power supply unit. This also supplies the µC in the actuator. The network side is supplied with control data from the low-voltage side via an optocoupler. This ensures galvanic isolation. On the network side there is a dimmer controller module, which in turn controls the triac. This controller must be supplied with a voltage of approx. 15V. To generate this, the manufacturer has built in a capacitive voltage divider. And this is where the aging problems begin …

The error pattern manifests itself as follows: The connected light source cannot be dimmed or switched on. However, the dimmer is communicating correctly with the bus. The red function LED lights up correctly. The commands for “Off” and “On” via buttons are also displayed in the CCU.

Circuit diagram of the mains side on the “main board”
defective 330nF X2 capacitor

The cause: According to the data sheet, the IC U2008, a dimmer control module, is supplied with a voltage of DC 15V. In this case, the supply voltage was significantly lower (at approx. 5.8V). This supply voltage is made the 330nF / 275V X2 capacitor C4. The capacitor is optically in perfect condition, but a simple capacitance measurement quickly shows that nothing fits here. The capacitor C4 only had a capacity of approx. 30-40nF. So it’s like so often -> It was the capacitor: D

Dimmer module side view

After the replacement, the voltage on the U2008 was ok again and the dimmer is doing its job again. As a preventive measure, the two other X2 capacitors on the board (C1 47nF / 275V and C2 100nF / 275) were replaced.

Installation locations of C1 and C2

 

 

 

 

 

 

Tidying up and archiving

Behind the title mentioned in the article headline is my idea of ​​tidying up the “ingmarsretro” blog and tidying it up a bit. By “cleaning up” I mean checking the individual posts again for spelling errors, maybe reformatting one or the other post and adding to it. That is why there will be no other contribution in January 2021.

There are also plenty of new posts that are digitally saved on the server, but there is no paper version of them yet. So I want to put all the posts that have been created since the last backup back on paper in the form of a book. And unfortunately that is not done in a jiffy, but requires a lot of work. The job and the “family time” with my little son only allow me to work on the contributions mostly at night. And between the posts I also work on the projects (little projects) that I then write about. I also have a lot of them in my head that may one day be realized. And then there are some that I’m working on that are still to be completed, or at least should be continued.

For the last few months I have been working on a Nixie clock that should be set up fairly discreetly. The watch has meanwhile also achieved a reasonable status, so that circuit boards from self-etched prototypes to reasonable, industrially manufactured condition have been created here.

the Nixie clock prototype

The “tube radio receiver” that I started with a few years ago is also waiting to be tinkered with.

Of course, the topic of retro computers does not let me go either. Here are a few devices left to restore and wait to be brought back to life. (This is where I remember right away: I’m looking for a RUN / STOP button for a Commodore Plus 4 – I would be happy if any reader could help …)

looking for a RUN / STOP key

The project with the MOS8501 CPU as a lattice – FPGA – mini board is also in the “carry on queue”. There is still a lot to do here (the level shifters are not doing as they should, the VHDL code still needs to be adapted, the prototypes Circuit boards have to be combined on one board and then also miniaturized …) So there is still enough to do.

Then there are also old devices that I would like to present here in the blog and a number of repairs that keep falling into my hands … Also one or the other HomeMatic tinkering is still pending.

I also toyed with the idea of ​​publishing content from the blog in the form of videos on YouTube. On the one hand, however, I cannot assess whether someone is interested and whether I would like to do that to myself, to present my face in front of the camera. It would probably make more sense to do it with a more didactically gifted person as the protagonist. And of course for Lau, as fun. On the other hand, there are quite a few Youtubers here who are very experienced here (e.g. Dave Jones with his EEVblog, NoelsRetroLab, Adrian’s Digital Basement, GreatScott, ZeroBrain, JanBeta, etc.) and have been doing this for a long time. Also not to be neglected is the immense effort involved in producing such films. When I look at my assembly videos here: It takes almost one day to record the raw material when soldering the respective kit and, in total, almost three days for the cut and post-processing. Let’s see if something can come of it one day …

 

 

 

The second book on the blog

After the great success of my first book on the retro blog, I have now made my way through and written a second book – NO FUN – there was no success at all. I wrote the book back then in order to have a printed work of my (in) deeds on this website for myself. Because, firstly, it is much more practical to be able to quickly check something – without always having an Internet available and secondly: what if the server (s) can no longer be reached, or is deleted, or even burns down? Or worse, if someone wipes the internet… 😀

At the time I thought to put it on with a “print on demand” option, but who knows if anyone will be interested and if I can even do it that easily. And who would spend so much money on it. Because the individual prints are also quite expensive. So the printed copies presented here are virtually unique. And I’m a little proud of it, because there’s a lot of work to be done.

So now there is the retro book no. 2 with the continuation of the blog entries from the end of the first version to the entry “Schuko socket with USB (repair)” from December 19, 2020 and that is again 96 “stories” which this time cover 498 pages. I chose “epubli” again for this print and ordered it there. This has the advantage that if I want to have one of the existing books printed, I just have to click on “order” again, since all the production data is already there.

I also learned a lot about the formatting of texts, fonts, step sizes and directories. The images are now printed at a higher resolution and all in all it looks better.

So I’ll stay tuned and in a few years, when enough content has been written again, I’ll be working on an issue again.

Solar – Radiometer

The Radiometer – also called lightmill – is an instructive, physical demonstration object that was invented about 100 years ago by the English physicist Crookes. This small physical-technical arrangement clearly shows how light is converted into mechanical energy.

 

 

The working princip of the solar radiometer:

Impeller inside the part evacuated glass ball

If warm light, ie sunlight, light of light bulbs or spotlights, meets with light in the spectrum of which the infrared component is present (but not cold light from fluorescent lamps) on the wing cross resting on a needle, this will turn depending on the intensity of the light source , In a particular method, a partial vacuum is generated in the glass ball, so that the air resistance is not stronger than the rotational force of the impeller generated by the light energy. The blackened surfaces of the wing cross absorb more light energy than the bright surfaces. Due to the warming of the air molecules, a much higher pressure is created on the dark areas than on the bright areas. This causes the constant rotation of the wing cross. (Brownian Molecular Theory). Depending on the light intensity, up to 3000 revolutions per minute should be achieved. (Source: Manufacturer of the Radiometer)

 

USB stick defective?

 

Again and again it happens to me that a USB memory stick loses its function and is suddenly no longer recognized. Often the stick is still registered as a drive in the system, but it lacks the disk, or even the system reports that the stick is not formatted. And even though he just recently, full of important data, has worked in another computer. 🙂 (Here would now be the story with the backups or backup copies …). All these problems are mostly due to operator errors or mechanical problems. For example, an operator error may be that the stick is being pulled while one more writing is in progress. The stick is then de-energized during a process. And depending on whether the controller or flash memory can handle it, the stick will survive or not. Often, mechanical defects are the cause of breakdowns. So it may be that the solder joints between the connector and the board break, or get the connecting pins of the quartz or oscillators contact problems.

In this case, I got a miniature stick from extrememory, which does not want to give away its stored data. It is displayed in the system administration, but if you want to access it, the message “no data carrier found” comes. The attempt to format or partition over diskpart from the commandline did not work. Also various tools like “SDFormatter” or “USBstick_Formattool” failed. Even with Linux or on MAC systems, no success was achieved. So a stick for the barrel … But I thought, even if the stick in its small design rather not close to a mechanical defect – why not take a look anyway 🙂 And at 16GB I will not give up so fast.

So I tried to gently open the case by first removing the metal case of the USB connector.

That works quite well. After I wanted to take a closer look at the appearing small printed circuit board with its tracks, there suddenly appeared something familiar.

That looks like an SD card. More specifically, like a microSD card.

That’s the way it was. The USB stick is nothing more than a MicroSD card reader, in which such a card is installed. Using tweezers, the SD card could be levered out.

Apparently here again the problem is with the contacts, or contact springs between card and card reader. It is the cause of the problem, because the SD card worked fine in another card reader and all the data was available. It pays to invest in front of the garbage bin for a few minutes and to inspect the innards of the device.

The storm glass – the weather forecast

Some time has passed since the last blog entry. On the one hand, I put this down to a lot of work, both professionally and privately, so that a bit of the energy for blogging was missing. The last days is the beautiful weather to blame. I preferred to spend my time riding a motorcycle instead of sitting behind the PC … But I also got a little gimmick again.

IMG_3952
FritzRoy storm glass

A colleague told me about it and at a large Internet mail-order company, I quickly found it. It is a so-called “FritzRoy storm glass“.

A storm glass is known for a long time from the seafaring. There it was used to predict weather changes. The storm glass is a glass cylinder filled with two liquids and hermetically sealed. The fluids are usually camphor and alcohol in saturated form, which do not mix but form small crystals. The formation of these crystals is related to the weather change. For a long time it was believed that the crystals react to changes in air pressure. Recent research allegedly suggests that the crystals react to electromagnetic fields called sferics. These sferics are preferably formed in low pressure areas. Thus, the storm glass shows the approach of a low pressure area and thus the bad weather.

 

IMG_3956
Crystals as weather forecast

The table (from the CarloMilano user manual) shows the different crystal weather relationships.

Clear liquid The weather is sunny and clear
Flaky liquid It is cloudy. Precipitation is possible
Small flakes It is foggy or damp
Little stars A thunderstorm is coming up
Little stars on a beautiful winter day It will snow
Big flakes It is covered. Snow is possible
Many crystals on the ground There is frost
Crystals on the surface It is getting stormy

Beware of electrical goods from the far east

DSC_2196The other day I noticed with a cold-device connection cable that the cable sheath has come loose in the area of ​​the strain relief. The wires came out. By itself, this is nothing special, if not here, apart from the unusual colors, the unusually small diameter of the wires in the eye would sting.

DSC_2199
left: cable without CE marking right: standard cable
DSC_2198
Plug without any test marks.

Normally, such a jacket cable with 16A / 250V and a CE mark is marked on the plug. The cross section of the stranded wires is 1.5mm².  The cable here on the photo but an indication of 10A / 250V was printed and NO CE sign available. The strands have a cross section of less than 0.5mm² !! Who uses such a cable and for example operates a heater with it, then may not be surprised if a quick fire breaks out … Unfortunately, I can not understand with what device I got this cable included. But it does not conform to the valid standards and represents a danger in the enterprise. In any case: Keep away from such products!

WordPress to Word.doc

If you wanted to save your Blogposts from WordPress, you will definitely know the XML export function in the Dashboard of WordPress itself. Here you can create and save an XML file in the menu “Tools” under “Export data” , This XML file can be used in a – for example – server error again to create the blog.

But what to do if you want to save your blog content in a Word file, or as a PDF, or even print? There are several possibilities to realize this. I will briefly list these variants here.

The latter tool I find personally very convenient and convenient, since it is very easy here to export his entire blog, including images in a Word document and postprocessing. All you have to do is export the XML file from wordpress.

converter0
chooese XML-file

After specifying the XML file, the blog posts are displayed directly in a list. Now you can choose which blog post should be converted and whether it should be a Word or PDF document.

 

converter1
window with exportable posts

Now you can start exporting …

converter2Depending on the number of posts and their length, the corresponding document is quickly available and can be edited as needed …

X-Mas 2016

Merry Christmas to the visitors of the blog!

Now it is already two years, in which I feed the “technology and retro blog” with contributions. Who would have thought that … By now some readers have strayed here and asked if I could introduce one or the other device here. Of course I will try to realize it if possible. Unfortunately, the rubric with the computers of the 80s is still empty. Here I still lack the “thread”, as I should process the whole – it floats me to every device before a small video in which the devices are to be shown in the living state. If someone has ideas for that … like.

I would like to say a big thank you to my colleague Mario Wehr, who provides me with the WordPress environment and thus offers excellent service!

In this sense: Merry Christmas and happy holidays!