Wednesday, August 30, 2023

Mailbag July 2023

A new mailbag post with some backlog mail.
(I planned to post this July mailbag begin Augustus, however it is already end August and some new interesting products have arrived for my next mailbag blogpost.

USB External soundcard.

As i want to experiment with audio signals i did buy an external to protect the sound chips of my computer

USB External soundcard.

Another sound card.
I was happy to have ordered 2 different cheap soundcards as my first experiments where more successful with this card that with the other one.

USB receiver

QRP Tranceiver
More connectors

Nice storage bag for cables
Cheap bluetooth USB led strip

A review of this product was already published on my blog

Air T split with valves

I want to make a ventilation system in my new shed using the Inline Blower.
This is a T splitter with 2 valves for the ventilation system.
This corner pieces also to use for ventilation system
Some more valves for the ventilation system
Cable binders (black)
Cable binders colored
Heatshrink, always good to use for electronic projects, you can never have enough
More connectors
Connectors with a small cable
Portable antenna
I hope to make a dedicated blogpost about this antenna 
Dupont / crocodile clip cabes

Mosquito killer lamp

And even more connectors

Thursday, August 10, 2023

Bluetooth USB led strip

This is a review of  a cheap Bluetooth USB led strip.

AliExpress advertisement campaign tells you you can buy 3 (or more) items from a selected list for US $1.99 or ~1.84 Euro each. Often interesting products can be found and i already did buy some of them. I stumbled upon a one meter USB Bluetooth RGB ledstrip. For this price it is an an interesting product and perhaps i can use it later in my new shed so i decided to put it on the pick list and ordered it.

Very soon it arrived together with other below 2 euro products in a packed in a separate plastic envelope. Here below a short review of the cheap Bluetooth USB led strip.

Bag with the led ledstrip

When powering the leds on a changing a red - green - blue light sequence started. According to the description it should be possible to control this led strip via Bluetooth. However there was no clear description how to do this.

On the cable is a small QR code. I tried scanning it however i was not very successful. I hoped the QR code would link to some vendor website or an app on the Google playstore for controlling the led strip.  Instead the QR  code linked to some (unrelated ?) TikTok video (i don't have TikTok installed). Perhaps when TikTok is installed a video about the device will be shown, however on my phone some unrelated TikTok movie started and i was asked to install TikTok. However i did not want to re-install TikTok just for this device after i de-installed it for security reasons some time ago,

QR code on led strip

On the vendor's page at Aliexpress was also no clue so i scanned for Bluetooth devices. My Android phone i did find a BlueTooth device named "ELK-BLEDOB". When connecting to it my phone told me i needed a special app for it.

After some quick searches on the internet this device name seemed for LedStrips and i decided to install some 'generic' app for led strips. In the Google App store i found an app called "duoCo Strip" and installed it. After installing i found a new app named "Lotus Lantern" and after a virus scan i started it.

 I did struggle a little to connect the bluetooth device in the app, however finally it worked and i managed to change the colors of the led strip, tested some of the sequences and also tested the color changing using music or sounds received by the smartphone microphone. For details see the help pages of the app. (you can find screenshots of this in this blog posting),

After disconnecting and reconnecting the USB led strip started using the last selected sequence. I did not test the led strip for a long time , sometimes i needed to reconnect it and also in the beginning the led's reacted relative slow to the app, however that improved during the use.

 In summary for this price (less than 2 Euro's) a nice USB powered 1 meter Led strip that can be controlled via Bluetooth.

Tuesday, July 11, 2023

Mini portable uninterruptible power supply (manual)

Some additional picture of the UPS shown in my last post 
My Mini UPS:

The manual:

Friday, July 7, 2023

Mini portable uninterruptible power supply

Recently i received this mini portable uninterruptible power supply (UPS) that i ordered after seeing a YouTube video of this interesting device. On AliExpress it is advertised as "Mini Portable UPS Router 5V 9V 12V Uninterruptible Power Supply for WiFi, Router Large Capacity Backup Power Adapter Ups Backup"

From the title you and seeing two Ethernet connectors you could think it contains a router or Wifi, however Ethernet connectors ar only available as this small power supply also can provide power over Ethernet (PoE). With a small switch you can select between 15V or 24V PoE.
Is also has a 5V USB outlet and 3 sockets providing  5, 9 and 12 Volt. It has a lithium battery and a circuit to act as UPS when main power stops. On top is an on and of switch and an indicator showing charging level. A European and USA type cable are provided for the main power voltage. Also included are a 'normal'cable and a 'split' cable for the 5,9 and 12 volt connectors.
It is a nice device that maintains power in the event of a power failure and provides some often used voltages. The 5V USB connector is also useful to have. It is not possible to draw all the advertised power at the same time and the power output is somewhat limited. For example it is not possible to power my FritzBox router using this device. If it could power my FritzBox i probably would have ordered immediate a second one to keep my network on in case of a power failure.

Product specification:

Battery capacity: 10400MA
Input: 85-265Vac
Frequency: 50-60Hz
Output: USB 5V/2A
DC 5V/1A
DC 9V/1A
DC 12V/1A
POE 15V/0.6A
POE 24V/0.6A
Output power (max):18W
Operating temperature:-10℃~40℃
Product size about:16CM*10CM*3CM
Weight 440 gram.

Below photos of the box and the unboxing:

Thursday, July 6, 2023

Cannibalizing an airplane headset


For experiments i needed a plug to make some connections. As, during the years i have collected airplane headsets i decided to cannibalize one and change it in a test wire, keeping the audio plug on one side and putting crocodile clips on the other side. 
I did cut the wire and removed some of the plastic insulation. The wires in the airplane headset where even more thin than i expected. Just a a thin metal wire with a thin layer coating on on it. I scratched away the thin coating and after measuring the connections i soldered a small wire to it and put new insulation using  heat shrink.
For the three distinct connections i wanted different colors. I had some new black and red alligator clips. Black is used for the common and red for the signal at the tip. An old, not so good, white alligator clip was also used. (On the photo it looks more yellow.) I cleaned the white "alligator jacket" and put the "jacket" on a new good "alligator".  The white alligator clip is for the for the middle ring of the plug.
The ear/hearing parts of the airplane headset where not needed yet. However as i already had the heat shrink with hot air gun and my soldering iron and some parts i decided to also make new connections on them.
To one earpiece i added alligator clips, to the other two banana plugs. I hope by adding this connections the hurdle to also use this earpieces, e.g. for a quick test, will be a lot lower. The earpieces where tested with my signal generator and they did work correct.