Category Archives: General

RPI4 Network Lesson

I learned something new last week-ending Aug 10, 2019)…. and now MORE…

I’ve set up countless Raspberry Pi 2 and 3 SBCs over time, usually headless and using the file /etc/dhcpcd.conf to set up a static IP address, It works every time. Or WORKED every time. Read on for some hopefully useful info…

Raspberry Pi 4 upgraded from a working Stretch to BusterWhen I got my new RPI4, I upgraded all my older systems to BUSTER, not one of the easiest things to do and indeed not recommended on the RPI-forums. (Use a clean installation, they say. GREAT unless you happen to have years’ worth of complex, only partly documented code on your RPI2 or 3.

Well, I did upgrade, the change is all documented on the blog – and of course when it came to setting a static IP address I never thought twice about it. I used my Buster-upgraded installation several times on the RPI4 without issue.

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Alexa, Raspberry Pi and Sonoff

Updated July 26, 2019: I am using a combination of Echo Dot generation 1 and generation 3 here in Spain.  

Amazon EchoAmazon insist on using port 80 for gen 3 Echos, a port already used by something else on my Raspberry Pi 3-based home control system.

I  am using port 8980 to avoid being the hated Linux ROOT user and so now, on my main Pi 3,  I moved the web server to port 86 and using “iptables” have redirected port 8980 traffic to port 80 to keep Amazon happy while continuing to use port 8980 to keep Linux happy as user Pi. This all seems to work well.

Continue reading Alexa, Raspberry Pi and Sonoff


Alfawise T9 Bracelet

tmpFC92To give it the full title, this entry is about the Alfawise T9 Body Fat Fitness Tracker (or Smart Bracelet). With a 0.96 inch screen, the T9 uses an App (Android or IOS) called Gloryfit (I use the Android version from the Playstore).

The bracelet uses an NRF52832 CPU and offers Body fat, Heart rate monitor, Sleep monitor, Pedometer, Multi-sport mode, notifications, camera remote, find-the-phone, alarm clock and much more.

The bracelet came from Gearbest and has detachable strap and comes with USB charger which works in any USB port. Note the readout (fat, water, protein) as well as time.

The bracelet/watch arrived completely flat and so I stuck it on charge for an hour.  So now, it is around 75% charged and I can give it a test. Here (above) it is on my wrist.

Continue reading Alfawise T9 Bracelet


Charger Doctor

No doubt you’ve seen ads for the little “Charger Doctor” gadget from China – well, my advice is to avoid it like the plague.  I have two of them, I’ve used them in the past but never on a Raspberry Pi. It turns out that given a 5.2v input, one of them reduces the output voltage to 4.8v, the other to 4.6v as measured by a 5-digit meter on the Pi edge connector.

Charger Doctor

If I take the same load, the same charger and the same short lead with no “Charger Doctor” inline – I get the original 5.2v. i.e. same start up conditions, same meter, same everything – the only difference being the presence or absence of the “Charger Doctor”.

Spec for Charger Doctor is 3.5v-7v in, 0A-3A out. The loss is not specified – and in my book is WAY too high.

In the bin – both of them.


Samsung Galaxy and Gear Watches

Samsung Gear S2 Classic BlackSo the latest is that the new Gear 4 watch won’t be called that at all, just Samsung Galaxy watch – and for anyone who has been living in a cave for some time(I have, but a cave with WIFI) can there be any doubt that this is the best watch in the world?

Personally I am running the Gear S2 (photo on the right) with no urgent desire to upgrade despite spending hours of gadget envy at various stores featuring the Samsung, Apple and other watches here in Spain and in the USA, not to mention dozens of websites) because I prefer the bezel on my 40mm Gear 2 as against the later, larger versions (which are also a little thicker). Up to now I’ve managed to avoid putting any marks on the S2 whatsoever. I have the Black Classic version with decent leather strap. In the past I’ve had lots of expensive “real” watches and no matter what they claim, eventually they get marks on them. I’ve tried really hard to look after this one, so far, so good (2 years down the line).

Continue reading Samsung Galaxy and Gear Watches


The Umidigi F1 Smartphone

Updated June 14, 2019:

So many phones out there, so much choice, so much rubbish. When it came to updating my own phone last year, I took advice from my friend Antonio (Mr Shark) and went for the Xiaomi Pocophone F1 and as it turns out, it was good advice as the Pocophone is an absolute winner. More of that elsewhere.

Umidigi F1

Now it is my wife’s turn and recently we took delivery of the Umidigi F1 phone from Banggood.Photo taken with Umidigi F1

The phone arrived here safely in deepest rural Spain, tracked and on time along with a separately shipped glass screen protector. 16/4/2019 - Above image taken this morning with the F1 back camera – no adjustments or enhancements.

My experience from opening the Umidigi package through to actual phone use is that of a high-end model phone – from the boxing and thank-you card from Umidigi themselves through the packaging effort by Banggood and to the phone and accessories, everything looks top notch.

Continue reading The Umidigi F1 Smartphone


Sonoff S26 Wifi Smart Plug

You may well have seen plenty of reviews and adverts for the Sonoff S26 WiFi Smart plug so I won’t go into too much technical detail here other than to say this VERY inexpensive wall socket can easily be re-flashed to run alternative software for those not to keen on relying on Chinese servers.

Sonoff S26

The S26 can be reflashed with nothing more than your PC and an inexpensive FTDI (USB to serial convertor) and can then run the excellent, free Tasmota software (sonoff release). Just be wary that the soldering connections are small.

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ESP GO update and more

A minor update for ESP-GO – still working on the Espressif SDK 3.1 version as RBOOT is still not OTA-ing reliably (everything else does)– but the SDK 2.1 version is working a treat – very reliable. There WAS an issue due to some recent updates, with the web setup – this crept in as I use serial to set up boards and didn’t notice a problem – that is now resolved thanks to efforts by Aidan Ruff who DOES use the web setup. See the main ESP-GO blog entry in here and also my Bitbucket repositories for more info on this well-developed and tested ESP8266 general purpose code - especially useful when using "the script" and for example a Raspberry Pi as a home automation centre as I and others do.

tmpCC3EQC3.0 Fast Charge Multi-port 5/9/12v Smart Travel Phone Charger
The rest of today’s postbag included a great little inexpensive Quick-charge-C wall charger (EU plug).  I now only use wall chargers which include a QC-3.0 output (you can never have too many) – as our phones charge much more quickly with this than normal USB output (which no matter WHAT the claimed output current at 5v,  will not fast-charge phones).

The orange output is Quickcharge, the other two are normal 5v USB at 2.1 amps – total output at any time, 3.1 amps. These units are available in a range of country plug fittings. I chose European 2-pin as I can use them in Spain and in the UK. The Gearbest website details the different types available. Pricing in the UK is 3.83 sterling with free shipping – but as I write this they may be out of stock so check.

QC3.0 Fast Charge :

tmp8467I also received a tempered glass front protector for my Xiaomi Pocophone F1 phone (don’t even think of using phones like this without a decent protector and these are DIRT cheap at around 2.70 pounds sterling and free postage to the UK and other countries such as Spain, France, Germany, USA etc. The unit comes in a nice box and is called Glass Pro+ XS. As my current plastic protector is scratched, this looks like a great upgrade with black surrounds.

Glass Film Screen Protector :

Umidigi F1 caseOCube Case for Umidigi F1 Play – Transparent
And last but not least a new back for the Umidigi F1 and F1 Play – this is a solid (as against soft rubber) case – clear with slightly frosted back – a nice rough finish which should last longer without scratching than many I’ve seen.

The thing is – you can’t beat the price -   around 2.30 pounds sterling and free shipping (at least to the UK, check for your region). Please note however that the shielding wraps fully around the sides but not fully over the top and bottom. However, the phone won’t fall out.

Phone Case for UMIDIGI F1 Play :


Blog changes

In order to minimise spam, I have removes some email subscriptions where the user names looked automated. This process is nowhere near perfect but is essential to protect valid readers/subscribers.

I’ve also changed email newsletter requests to double-opt-in – that is, if you newly request emails from the blog, you may be asked to confirm your email address. I apologise in advance for any inconvenience to registered blog readers.

While I’m here – has anyone been watching the media coverage of the new folding Samsung phone (and others)? I know this is technically neat but am I alone in wishing manufacturers would concentrate on the things we really want and in some cases need? Improved charging/battery life would be good. Better cameras, by which I don’t mean much higher resolution, but vastly improved low-light performance and optical zoom would be good – even if that means new lens technology. Do we really need higher resolution for selfies? Probably not. Let’s see real innovation, guys.


EleksMaker Pro Laser Engraver

Update February 28, 2019
Last year year I put together this excellent A3 laser engraving machine. Originally, a 500mW laser module arrived complete with its own power supply (the laser which was not included in the basic kit). It turns out that was the wrong laser and now I have the 2300mW violet laser complete with upgraded 2.5A power supply. In the photo you also see the (important) green protective glasses that came with the kit.

Cutting door signs with Eleksmaker

Continue reading EleksMaker Pro Laser Engraver


BigTimer and getMoonTimes

I just spent ages debugging issue with theSunCalc module used in Node-Red-Contrib--BigTimer.

It turns out that the getMoonTimes module doesn’t seem to handle the alwaysUp and alwaysDown methods the way one might expected – these do not return FALSE  if not TRUE – they return undefined – that took some figuring out.

I started with try-catch but that failed also. Simply checking as follows did the trick:

if (typeof moons.rise==='undefined')
date2=moons.rise; moonrise = (date2.getHours() * 60) +

if (typeof moons.set==='undefined')
date3=moons.set; moonset = (date3.getHours() * 60) +

I’m pretty sure this is now fixed as of BigTimer 2.1.7

Thanks to Aidan Ruff for his help in this one.