Few stories - Build something on it.

I'm building something. As usual.
I'm telling a few stories about things - unusual? I don't know.

1. I'm fundamentally an IT guy. Most of my life I worked in various companies fulfilling various IT jobs. This dates back when I was head of the IT plus sysadmin at a company called "Láng Holding".
This was before the internet era (just to understand, the internet was existing way before some of the younger or not core IT people thinks). So it dated to 1998-1999 (Before the dotnet boom).
We acted as a usual holding company. Mainly working as financial/legal entity. One of the biggest IT challenge at those days was to have the countries laws, the country wide corporate registry available electronically for our employees. At that time this information was not available on the just starting web.
There were a company who provided this information on subscription based CDROMs.
A usual computer has only one CDROM drive (mostly non today), but I needed more, centrally on the server. So I bought a nice SCSI box with four drive bays and four SCSI CDROMs for the task.
Those days passed. We finally closed this company, and the box above landed in my loft (together with many old IT things).

2. A few weeks ago I ordered two identical 60V/1500W DC power supply modules from China. As I didn't wanted to pay the higher shipping cost of DHL, I ordered them separately. It costs $99 each.
This was a good test of the local post, how they handle the customs. I can tell: randomly.
The first one I ordered landed at customs, and still didn't arrived to me. The second one I ordered landed in my house without customs handling.

3. Back in 2017, I ordered a Ruideng DPS5020 power supply module from Banggood. After a few month it become clear, that it will never arrive. So I complained, they resent it, and after a while both arrived. I agreed with them to keep both instead of sending one back.

As you may realized by now I want to build a dual channel 0-50V/20A power supply to my lab. This is in my mind since 2017.
As I have both the lab supply modules and the huge mains power supply for it, I started to think, what would be the best possible enclosure for it. All the ones I found at the local suppliers and the online sources were too big and too costly. Then come into my mind the forgotten SCSI box from the loft:

Removed everything from inside:

Built two power modules from the Ruideng controller and the 1,5kW PSUs added some aluminum profiles:

Mounted it into the box above:

Here come a few problems:
1. I started to think. The box has 3kW PSU inside. I think, the original power switch will never be able to handle around 15A current.
2. I don't want to switch those PSU simultaneously on, because the mains fuse will not handle the inrush current
3. I want to control the PSUs from a PC, but on a single USB port. So I need to change the USB/RS232 adapter came with the units to something else.

As you see the build almost finished, I just need to address those issues. Especially to first two. Those will come in a later article.

Hi-Fi rack - Motorized turntable shelf

I started to build a rack to my retro Akai set. I'm a small guy. When I started to plan the rack I realized that I loose space in the rack if I put the turntable on the top of it (it can't be taller than 120-130cm). If I build a 170 tall rack and put the turntable into the middle of it I still loose space, as I should open the lid somehow.
What if I build a shelf can be pulled out with the turntable? This way I not loose space. Think this a bit further: add a motor for the shelf.
Ok, but how to control the shelf?
What if I add an aluminum profile to the front of the shelf and use it as a touch sensor?
And the result:

The controlling electronics today contains an Arduino UNO, a CNC Shield, a DRV8825 motor driver and a few additional components on a breadboard.
This is not the final solution. I intend to build a specialized electronics for this. Change the motor controller to a Trinamic one because this is too loud now.

Akai - Media Player 2. Volumio

I dowloaded and put on a microSD card the Volumio
Connected to HDMI, keyboard, switched on - nothing on the screen (maybe the screen resolution)
Moved the set to a 4K TV - nothing on the screen
Removed the Wi-Fi module - nothing on the screen
Switched the Pine64 board to completely new - nothing on the screen
Changed the microSD card to a different piece, manufacturer - nothing on the screen
Changed the microSD card to my previously used Android TV distribution - screen on, booting
RTFM - you are an idiot. The Volumio is headless on SBCs

Connect to the LAN, wait for IP, connect via browser

First task accomplished
I need a few plug-ins for the complete system:

Tidal (I'm using mainly as music streaming)
Looked around. I'm not happy. Looks like the native integration doesn't exists. You have a few choices:
1. Subscribe to MyVolumio and use Tidal through it
2. Download your music locally with AudFree
3. Stream through UPNP/DLNA from your Android phone
I can tell, I'm not happy with either choices. Not yet decided, what to do.
Further reading:
https://forum.volumio.org/tidal-playback-t8894.html
https://www.audfree.com/tidal/tidal-on-volumio.html
https://forum.volumio.org/tidal-native-plugin-myvolumio-t10682.html

16x2 (20x2) LCD display - hopefully my VFD use the same communication protocol
It looks like there is quite a lot information exists on the internet. I just need to grab them, and build. The question is, how will it work on the Pine64 as all of the descriptions for Raspberry Pi.
Here are the Github repositories for the code:
https://github.com/Saiyato/volumio-pydpiper-plugin
https://github.com/dhrone/pydPiper
https://github.com/JedS/Raspdac
Connection:
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhDN0xib8RQp84p4BqSTxCumE6uhyphenhyphen2iqGubwXm-KATwOJx0sHPCs1NKIhWuSWM56k99GLX91C0lwPjYfspIR3Jhl_yviuIMxvLpiiFX3ck0547TcxwAUciyi3cRbKmU0u9lV6lM20T8SfBj/s1600/Volumio+LCD+1.jpg
I2C Interface (not yet decided, if I'll use it):
https://forum.volumio.org/display-16x2-and-i2c-interface-t9549.html

Rotary Encoder
It looks like the rotary encoder plugin already in the stock firmware, so I installed it already.
Here is the documentation and connection:
https://github.com/Saiyato/volumio-rotary-encoder-plugin
I read on various pages, that this is unreliable. Here is a different solution:
https://forum.volumio.org/getting-rotary-encoder-working-t9690.html
We will see, what is the working solution.

Buttons/GPIO
The chassis contains three buttons already. My plan is to keep them, and use them for... I don't know yet. I'll figure out later. probably I'll relabel the buttons.
Anyway. Here is the plugin:
https://github.com/tomatpasser/gpio-buttons
https://github.com/volumio/volumio-plugins/tree/master/plugins/system_controller/gpio-buttons

Bluetooth
I'd like to play music from my phone through bluetooth. So looked for the solution. Here I found one:
https://forum.volumio.org/volumio-bluetooth-receiver-t8937.html

Infrared Remote
Here is a starting point for the infrared remote I plan to use:
https://forum.volumio.org/control-guide-for-raspberry-t9700.html

Now I collected all of the information I think is necessary for my VolumIO project. I'll continue from here connecting, setting up piece-by-piece.

Akai - Media Player 1. SBC

In the previous post I was writing about Raspberry Pi as the computer will be used in the device.

I was thinking a bit further and realized it is not the ideal solution. (Still, I think the Raspberry Pi is an awesome piece of hardware, just doesn't fit into this particular task)

The features I miss from the RPi:

Internal USB

I need a USB connector can be extended to the front panel to be able to play music from a USB stick

On RPi all of the USB connectors are on the same side as the Ethernet what I would put to the back of the unit (this could be hadled different way, but I have other things)

External Wi-Fi, Bluetooth antenna.
The case is made from metal. Probably the Wi-Fi and the Bluetooth would barely work inside the case. I found hack on the internet to overcome this, but this is a hack.
So I looked around, the internet, found a few feasible solution, what kind of board should I buy. On the other hand, I have two problems with those:
I have plenty SBC-s on hand, don't want to spend money on an additional one
If I order something from the net, it take a few weeks to arrive. As I ordered the DAC and the display previously, probably the  SBC would arrive latest
So I dig into my development board/SBC box in my workshop. I realized that the board I have many of it (at least 5) completely satisfy my needs.
The brain of the media player is switched from Raspberry Pi to Pine64.

I'm still not totaly convinced in my choice, therefore I'll not build it into the case right now, just assemble it on my desk and start to experiment with it.
Here I found a reasonably new release of the VolumIO for my Pine64:
https://forum.volumio.org/volumio-pine64-pine-a64-lts-sopine-compute-module-t9465.html
I'll continue my journey with this.

Akai - cannibalized

As I wrote previously, I want to add streaming media capability to my retro Akai Hi-Fi set.
The plan was the following:
Pick up on the market a low cost unit, fits into my set.
Remove everything from inside.
Build the following set into it:
- Raspberry Pi + VolumIO
- Some power supply
- Some DAC
- Some alphanumeric display
- Rotary encoder
- IR receiver

I was looking for the possible "donor" units. Finally my choice is an Akai AT-A1 tuner. I bought the one I have in my hand for GBP 17 from UK

Opened the box. Here is the original inside:

Then I removed everything what looks unnecessary:

Ordered a few things what will go into the box:

This is the current status. More will come soon.

Akai - old love

I didn't write this blog for a while. I had good reason for this, what is not public. From now on it looks like my reason went away, so I'm back.
Along with my passion for electronics, CNC milling, 3D printing and many more, I have an old love. Music and Hi-Fi. To be honest originally this was bringing me into the world of electronics almost 40 years ago (38 to be exact). I was 11 when the first Hi-Fi set landed in my family. Right from the beginning I was thinking how can I expand its capability, later on I was thinking how can I rise its sound quality. This lead me into the word of audio electronics, building amplifiers and other things.
As I raised behind the "iron curtain" in the '70s and '80s. At that times not to much goods arrived from the western part of the word. Here in Hungary mainly one company namely Akai was available, based on the fact that Videoton (Hungarian audiovisual manufacturing company) acted as a manufacturing base for Akai here.
At 1984 even they had a trade show in a restaurant in Budapest. I was there and picked up a brochure, what was almost a Hi-Fi bible, a source of wishes for a long time. I just wanted to own a full set of highest ranked equipment from this brochure - what unfortunately don't have anymore.
In the last year somehow pop this desire into my mind after a long time forgotten.
So I started to collect.
Today I can tell, I almost have the full set I wanted. Actually even a bit more, but the "project" not finished. I'll probably sell a few, switch a few from it.
Here is the current collection:

Some of the units are in a good shape. Some of them need care both outside and inside. In the following months even years I plan to restore those into working, aesthetically good condition (also with some external help).
In addition to this I plan to create a shelf to accommodate all of the units I intend to keep, and add some capabilities what fits into the design, but was not available at the time this equipment was built, like internet streaming audio.

What arrived?

I continuously ordering things from various places, but frequently I don't write about.
Here are three things what I think can be interesting in some ways.
Recently I started to work on integrating my measurement equipment with my lab PC. It is getting important as I have a few measurement in my head, what requires such kind of integration.
The instruments in question have various interfaces: USB, RS232, GP-IB, Ethernet. Talking about the first three, at the end of the day the connection for the PC will require USB ports. Lots of USB ports.
So I ordered a USB hub on AliExpress.
I hope 16 ports will be enough:

Keep talking about instruments. As I see, it is handled as a fact that for measurement process control the used application is NI LabView. This software used for many things. Even the Lego is using it for controlling the Mindstorms kits. For a long time now, I'm using mainly free or open source software, if it is not available, I'm buying it.
The LabView as such is a software with horrible price tag. It is just came to my attention (you may already know it), that NI made available a Home Bundle version. Yes, it is not the latest, yes it is just for not profit home use. But, it cost $50, what can be payed by a serious hobbyist. So I have it now:

I hope, it will help me to automate my measurements.
There are running a promotion/contest by Microsoft and Avnet (https://www.element14.com/community/docs/DOC-92683/l/sensing-the-world-challenge). It is about connecting to Azure IoT.
I even have a MAPS subscription, so I have $100/month allowance for Azure.
I become an AWS guy in the last 6+ years. I feel this contest a good opportunity to widen my perspective and learn a bit more about Azure.
So, I ordered the kit for free, and it arrived yesterday:

Even, I have an idea, what to build from it.