Category: hardware

Samsung ML-1520 on OS X 10.12 (Mac OS Sierra)

Published on: 01.02.2018

I do not like doing upgrades

Especially operating system (OS) upgrades.

The reason, why I do not like them, is because usually after update something is not working as before or even not working at all.

The feature from software is changed, drivers not available anymore, software is not working with a new OS, sometimes new OS is slower than old one, etc.

The only reason why I do upgrade is if I have to (some feature is only working on new OS) or have new hardware (then anyway I need to install OS so I can try the last version).

Regularly I upgrade only iPhone and iPad because I do not use it for work, more for fun (if some software is not working anymore I can live without it).

I bought new SSD

For my 7 years old computer, I decided to upgrade my HDD to SDD because it was the bottleneck.

Upgrade will be done from OS X 10.9 to OS X 10.12.

At that time 10.13 was available as a beta.

But I will not use the beta if I do not have to.

When I did iPhone development with XCode I usually had to use newest OS X to have access to the last SDK.

Always test before upgrade

Luckily I have one Mac Mini, so I decided to do a test installation on it first.

So that I am sure that all software that I use is working fine before I upgrade my main computer.

The biggest problem I had with my Samsung ML-1520 laser printer.

I do remember that even on OS X 10.9 it was also not working by default, but with I manage to have it working.

On OS X 10.12 are still needed, but will not get the job done.

After 2 hours, I manage to have it working on OS X 10.12 (Mac OS Sierra) but it was not easy.

652 WLXKJ USB network server

I have Samsung ML-1520 connected to 652 WLXKJ USB network server so that I can share Samsung ML-1520 as a network printer.

For last 7 years, 652 WLXKJ is working with no problems.

There is no official support for it (I do not even know who made this thing), and you have to figure things on your own (like to add USB stick to it, if you want to use it as network print server).

652 WLXKJ USB server
652 WLXKJ USB network server working with 15 years old USB stick

Samsung ML-1520 on OS X 10.12 (Mac OS Sierra)

The only way how I have found that Samsung ML-1520 laser printer can work with OS X 10.12 (Mac OS Sierra), is to add a PPD (Postscript Printer Description) file manually but must also be installed.

Luckily, PPD file is available at SpliX website, download the source code, unzip it, ml1520.ppd is inside splix-2.0.0/ppd.

There is also ml1520fr.ppd (French language) and ml1520pt.ppd (Portuguese Brazil language), .

After this printing of PDF and DOC documents did work (and I have only tested with PDF and DOC documents).

Steps for installing Samsung ML-1520 on OS X 10.12 (Mac OS Sierra)

Install Splix-2.0.0.mpkg

Splix-2.0.0.mpkg can be downloades from as, unzip it and install it.

You will have the error message The installation failed but this is fine, you need to have, I know it is strange.

the error message The installation failed after installing Splix-2.0.0.mpkg, but this is fine

This is an important step, if you do to it, later when you install Samsung ML-1520 you will have The software for the printer was installed incorrectly. Please reinstall the software from the manufacturer error message and Samsung ML-1520 will not work.

error if Splix-2.0.0.mpkg is nto installed

Add ml1520pt.ppd Postscript Printer Description for Samsung ML-1520

all information from Samsung ML-1520

Add Samsung ML-1520 in System Preference... inside Printers & Scanners
Most important is to in Use: select Other... and then Open file ml1520pt.ppd, remeber you need to download it from SpliX website.

Address:, Protocol and Queue: are specific in my setup because I am using it with 652 WLXKJ USB network server.

When all is finished, Samsung ML-1520 is working fine.

Samsung ML-1520 working fine

This is why I do not like upgrades.

Hopefully, this will be helpful to somebody.

Computer setup, electricity consumption

Published on: 01.08.2017

My current computer setup (in 8/2017) is
Apple MacBook laptop “Core 2 Duo” 2.4 GHz 13-inch with
Dell 24-inch UltraSharp Monitor – U2412M


I was surprised how little electricity is used by computer and monitor.

All together it is maximum of 50 Watts, so for 1 kilo Watt hour, 20 hours of work is needed.

I remember how CRT 15 inch monitor was using 70 Watt.

Pentium 3 was using 55 Watt and Pentium 4 was using 130 Watt, at 100 CPU.

Even my 19 inch HP L1950g is using 30 Watt.

What is much more than 24 inch and it is much smaller than 24 inch.

Planned obsolescence from Apple

In MacBook I have 10 GB of DDR3 1067 MHz memory.

Originally I had 4 GB but that was too little, so I had idea to put 16 GB inside 2x 8GB.

But, for ever reason (I think that Apple have some software/hardware lock, so that you need to buy new laptop and can not just install more memory) 2x 8 GB did not work, I could not boot it.

With try and error, I found that if I leave original 2 GB in one slot and put 8 GB in another slot that it is working fine and that is how I have 10 GB.

Basics of electricity consumption

This will just be basic introduction to electricity consumption, so that you can understand what is Watt.

For electricity consumption you always have two parts:
– electric current, it is measured in ampere
– voltage, it is measured in volt

To get electricity consumption you need to multiply electric current(ampers) with voltage(volts).

Unit of measurement for electricity consumption is called Watt.

Usually electrical devices are rated in Watt/hour, what just means how many watt will some device use in 1 hour of their work.

Electricity consumption of monitor

Electricity consumption of monitor depend on how white/bright is your screen.

So you can separate it by brightness and main color of screen.

Table show some real measurements.

Main Background Color Brightness
0% 75% 100%
White 10.9 Watt 20.3 Watt 22.7 Watt
Black 8.2 Watt 17.3Watt 19.9Watt

More brightness use more electricity, same is with white color.

I also have tested contrast, but contrast does not have big impact.

With brightness and contrast set to 0%, electricity consumption was 7.9 Watt, regardless of background color.

But with brightness and contrast set to 0%, you just have black screen with just small back-light, so it is not useful.

With brightness and contrast set to 100%, electricity consumption for white color was 22.9 Watt and for black 19.9 Watt.

I have my monitor brightness and contrast set to 75% and electricity consumption was never above 20 Watt.

When Flurry screensaver is running it is 17.6 Watt.

For one kilo Watt to be used, with biggest possible consumption of 20 Watt, monitor need to be on for 50 hours.

Electricity consumption of MacBook

MacBook is laptop, so it has a screen, but screen brightness had little effect on electricity consumption.

Maximum difference between 0% and 100% brightness was 4 Watt and this was at load of 100% CPU.

When CPU load was at 10%, when computer is not in active use, difference was at 2-3 Watt.

Table show some real measurements.

Test Brightness
0 % 100%
CPU 10% 15 Watt 17 Watt
CPU 100% 28 Watt 32 Watt
Flurry screensaver 8 Watt 20 Watt

My regular work is at 25% CPU.

As it can been seen from table, main part of electricity consumption in computer is CPU load.

All this measurement as done with Dell 24-inch monitor connected to MacBook.

I did same measurement with Dell 24-inch monitor disconnected, difference was just in 2-3 Watt.

Electricity consumption some of my other equipment

iPhone 4 use 10 Watt to charge Battery from 0% to 100%.

iPad Retina Mini use 35 Watt to charge Battery from 0% to 100%. After 20 charging that is 1 kilo Watt, what I spend per month and I use it every day few (around 3) hours.

Additional explanation of measurements

I have used Velleman NETBSEM5 ENERGY METER for measuring electricity consumption.

For white Main Background Color I used

For black Main Background Color I used, look-like they really save electricity.

To get CPU at 100%, just yes > /dev/null & was used.