Friday, December 18, 2015

Barcelona Projection show / Barcelona town hall facade

Memories from my stay in Barcelona, i think it was 2013. Already three years passed. Time flies really fast. I was walking when i saw people outside the town hall, and the show started.  You can get here a taste what i saw. It seems that they have the light show every year.








Thursday, December 10, 2015

Vim and Bash example settings

From time to time i have to work on a new machine or i had to install a fresh version of my favorite Linux distribution. Every time i spend time for preparing two setting files: the .bashrc and .vimrc. Here are my personal setting for vim first:

" Authors: http://vim.wikia.com/wiki/Vim_on_Freenode
" Description: A minimal, but feature rich, example .vimrc. Modified by
" Michail Alvanos. 

 
" Set 'nocompatible' to ward off unexpected things that your distro might
" have made, as well as sanely reset options when re-sourcing .vimrc
set nocompatible

set noexrc " don't use local version of .(g)vimrc, .exrc
set background=dark " we plan to use a dark background
set fenc=utf-8 " UTF-8
set cpoptions=aABceFsmq
set statusline=%F%m%r%h%w[%L][%{&ff}]%y[%p%%][%04l,%04v]

colorscheme elflord

" Attempt to determine the type of a file based on its name and possibly its
" contents. Use this to allow intelligent auto-indenting for each filetype,
" and for plugins that are filetype specific.
filetype indent plugin on
 
" Enable syntax highlighting
syntax on
 
 
" Must have options 
 
" Allows you to re-use the same window and switch from an unsaved buffer
" without saving it first. Also allows you to keep an undo history for
" multiple files when re-using the same window in this way. 
set hidden
 
" Alternatives include using tabs or split windows instead of re-using the same
" window as mentioned above, and/or either of the following options:
" set confirm
" set autowriteall
 
" Better command-line completion
set wildmenu
 
" Show partial commands in the last line of the screen
set showcmd
 
" Highlight searches 
set hlsearch
 
" Use case insensitive search, except when using capital letters
set ignorecase
set smartcase
 
" Allow backspacing over autoindent, line breaks and start of insert action
set backspace=indent,eol,start
 
" When opening a new line and no filetype-specific indenting is enabled, keep
" the same indent as the line you're currently on. Useful for READMEs, etc.
set autoindent
 
" Stop certain movements from always going to the first character of a line.
set nostartofline
 
" Display the cursor position on the last line of the screen or in the status
" line of a window
set ruler
 
" Always display the status line, even if only one window is displayed
set laststatus=2
 
" Instead of failing a command because of unsaved changes, instead raise a
" dialogue asking if you wish to save changed files.
set confirm
 
" Use visual bell instead of beeping when doing something wrong
set visualbell
 
" And reset the terminal code for the visual bell. If visualbell is set, and
" this line is also included, vim will neither flash nor beep. If visualbell
" is unset, this does nothing.
set t_vb=
 
" Enable use of the mouse for all modes
set mouse=a
 
" Set the command window height to 2 lines, to avoid many cases of having to
" "press <Enter> to continue"
set cmdheight=2
 
" Display line numbers on the left
set number
 
" Quickly time out on keycodes, but never time out on mappings
set notimeout ttimeout ttimeoutlen=200
 
" Use <F11> to toggle between 'paste' and 'nopaste'
set pastetoggle=<F11>
 
 
" Indentation options
 
" Do not change 'tabstop' from its default value of 8 with this setup.
set shiftwidth=4
set softtabstop=4
set expandtab
 
" Indentation settings for using hard tabs for indent. 
"set shiftwidth=4

And my .bashrc:

# If not running interactively, don't do anything
case $- in
    *i*) ;;
      *) return;;
esac

# don't put duplicate lines or lines starting with space in the history.
# See bash(1) for more options
HISTCONTROL=ignoreboth

# append to the history file, don't overwrite it
shopt -s histappend

# for setting history length see HISTSIZE and HISTFILESIZE in bash(1)
HISTSIZE=1000
HISTFILESIZE=2000

# check the window size after each command and, if necessary,
# update the values of LINES and COLUMNS.
shopt -s checkwinsize

# If set, the pattern "**" used in a pathname expansion context will
# match all files and zero or more directories and subdirectories.
#shopt -s globstar

# make less more friendly for non-text input files, see lesspipe(1)
[ -x /usr/bin/lesspipe ] && eval "$(SHELL=/bin/sh lesspipe)"

# set variable identifying the chroot you work in (used in the prompt below)
if [ -z "${debian_chroot:-}" ] && [ -r /etc/debian_chroot ]; then
    debian_chroot=$(cat /etc/debian_chroot)
fi

# set a fancy prompt (non-color, unless we know we "want" color)
case "$TERM" in
    xterm-color) color_prompt=yes;;
esac

# uncomment for a colored prompt, if the terminal has the capability; turned
# off by default to not distract the user: the focus in a terminal window
# should be on the output of commands, not on the prompt
#force_color_prompt=yes

if [ -n "$force_color_prompt" ]; then
    if [ -x /usr/bin/tput ] && tput setaf 1 >&/dev/null; then
 # We have color support; assume it's compliant with Ecma-48
 # (ISO/IEC-6429). (Lack of such support is extremely rare, and such
 # a case would tend to support setf rather than setaf.)
 color_prompt=yes
    else
 color_prompt=
    fi
fi

if [ "$color_prompt" = yes ]; then
    PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\[email protected]\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
else
    PS1='${debian_chroot:+($debian_chroot)}\[email protected]\h:\w\$ '
fi
unset color_prompt force_color_prompt

# If this is an xterm set the title to [email protected]:dir
case "$TERM" in
xterm*|rxvt*)
    PS1="\[\e]0;${debian_chroot:+($debian_chroot)}\[email protected]\h: \w\a\]$PS1"
    ;;
*)
    ;;
esac

# enable color support of ls and also add handy aliases
if [ -x /usr/bin/dircolors ]; then
    test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"
    alias ls='ls --color=auto'
    alias grep='grep --color=auto'
    alias fgrep='fgrep --color=auto'
    alias egrep='egrep --color=auto'
fi

# some more ls aliases
alias ll='ls -alF'
alias la='ls -A'
alias l='ls -CF'

# Add an "alert" alias for long running commands.  Use like so:
#   sleep 10; alert
alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'

# Alias definitions.
# You may want to put all your additions into a separate file like
# ~/.bash_aliases, instead of adding them here directly.
# See /usr/share/doc/bash-doc/examples in the bash-doc package.

if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
fi

# enable programmable completion features (you don't need to enable
# this, if it's already enabled in /etc/bash.bashrc and /etc/profile
# sources /etc/bash.bashrc).
if ! shopt -oq posix; then
  if [ -f /usr/share/bash-completion/bash_completion ]; then
    . /usr/share/bash-completion/bash_completion
  elif [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
  fi
fi

#export ANDROID_HOME="/opt/android-sdk-linux/tools"
#export ANDROID_PLATFORM_TOOLS="/opt/android-sdk-linux/platform-tools"
#export PATH="$PATH:$ANDROID_HOME:$ANDROID_PLATFORM_TOOLS"

Thursday, November 26, 2015

How to setup custom tk domain for your blog

I was wondering these days if there is any free domain name provider. After a bit of googling i discovered the freenom.com site that can provide tk domains for free, but you have to renew it every year. The site also allows to register .com sites. I wrote a walk-through how to do this:

Step-1: Go to freenom.com or dot.tk and search for the domain you want.


Step-2: If the desired domain is available then you continue with the domain registration

Step-3: Click Order Now button. Here you have to verify your account by email. Verification link usually comes after 4-5 minutes.


Step-4: Go to Blogger Settings and find Publishing option in your dashboard.

Step-5: Then enter your Tk domain with www in the empty textbox.

Step-6: Hit Save button, you get a Error: "We have not been able to verify your authority to this domain. Error 12." Google provides you with two CNAMEs.

Step-7:  Go to Freenom site in a new tab and click on Domain Panel and then click on “My Domains”.

Step-8: Now click on "Manage Freenom DNS" and it will take to DNS MANAGEMENT.

Step-9: First of all Select “CNAME Record” from type option then write “www” in Name and “ghs.google.com” in Target. Next copy the other information provided from Google.

Step-10: After 10-15 minutes return to the open page of the blog and press save. Our site is up. Check it here: www.malvanos.tk

Saturday, November 21, 2015

Sunset Nicosia

Enjoying the sunset from my new home in Nicosia. Not the best city to live in, but not bad either. I just wish it had less traffic and more... green as every big city.

Sunset in Nicosia, Cyprus over the buildings.
Sunset in Nicosia, Cyprus over the buildings.
Sunset in Nicosia, Cyprus over the buildings.
Sunset in Nicosia, Cyprus over the buildings.

Friday, November 20, 2015

PC Gaming + Nostalgia

Not long ago i remember buying my 3dfx Voodoo3 3000 and running my old games. I remember the huge difference that the hardware transformation and lighting could provide. I was fanatic of Need for Speed III: Hot Pursuit at this period. I had a good friend from the neighbour home and from time to time we were playing together in the PC trying to make the best time. I still remember his expression when we lunched the NFS again and saw the new graphics. My setup was a Cyrix 6x86 350 running at 250MHz with 32MB of ram initially that i upgraded them to 96MB later. My first graphics card had something like 4MB and with the upgrade to Voodoo3 3000 i went to 16MB. Enormous difference. Take a look on the difference of using Software vs Glide of 3dfx:




At that period i was using my PC mostly about playing games and nothing else. So the first thing i did is to install the games included with my 3dfx card. I remember two or three games. The first was the Descent 3 and the other one, what i played the most the Unreal.... When i first saw the graphics, i just said.. wow. This is not possible, my PC can't create these graphics real time and with vast open spaces. It was just a new machine. Just to get an idea of the intro screen:



Recently i stumbled upon a video regarding History of games. I will suggest you to watch if you ever played games and interested in the history.




Thursday, November 19, 2015

Acropolis of Rhodes

The Acropolis of Rhodes is an acropolis dating from the Classical Greek period (5th–3rd century BC) 3 kilometers from the center of Rhodes in Greece. There are a number of monuments that someone can visit, including the temple of Apollo, the stadium, and the ancient theater.

I have a good friend that prepared a very nice video of this area:



I also included various photos from the area:
City of Rhodes, Greece, Acropolis

There is also an ancient stadium that exists nearby the acropolis temple:

  Rhodes Acropolis Circus

Monday, October 26, 2015

Looking at the sun using a Celestron Astromaster 70 and a solar filter

Couple of months ago i got the idea of observing the sun using a solar filter. I ordered a cheap solar filter from Israel and  placed it front of the telescope. Note that you have to adjust the filter in front of the the telescope not between the body and the eyepiece because high temperature can be developed inside the telescope's tube.

Solar filter attached to the telescope.

Solar filter attached to the telescope.

The next step was to point to the sun. Compared with the night sky it is really hard to target the sun, as you can't look (or you shouldn't) directly to the sun. The easiest trick is to align the body of the telescope with the sun to minimize the shadow created as shown in the next two pictures:



Aligning the telescope to the sun using its shadow.
Aligning the telescope to the sun using its shadow.
Finally, we align as perfect we can the telescope. I aligned the telescope without the eyepiece because it was easiest to move it.


The final result, note the sunspot on the right. Not perfect aligned and not the best quality, but for the 20$ price tag of the sun filter is a good opportunity to explore the sunspots.

Photo of the Sun using the celestron travelscope and the sun filter.
Photo of the Sun using the celestron travelscope and the sun filter.

Saturday, October 17, 2015

The Old Medieval City of Rhodes - video

A good friend of mine, Stavros Ladikos, makes his first steps on video production. One of the recent videos produced is for the old town of Rhodes. Enjoy:


Tuesday, June 9, 2015

NOAA 19 Signal received using a RTL-SDR DVB-T usb receiver

A couple of years ago I tried to receive the NOAA 18 using a small in-door antenna and an RTL DVB-T USB receiver. The results were disappointing. However, I always had in the back of my mind that I will try again in the future with an external antenna. The era of cheap RTL-SDR hardware has come, so many people have started looking for receiving images from the weather satellites. Easy targets are the NOAA satellites that transmit weather images using Automatic Picture Transmission method (APT). These satellites provide images in different wavelengths of light.

So after following instructions from a site dedicated to the RTL-SDR receivers, I tried to receive some pictures using the simple TV antenna. However, this decision had many disadvantages, as the TV antennas are designed to receive signal on higher frequencies from NOAA satellites. Despite the poor reception and low cost (e.g.,. none, I had an old tv antenna installed, but not used) I was able to receive some pictures. I used the SDR# with the RTL-SDR plugin for receiving the signal (sound), orbitron for tracking the satellite, and WXtoImg for converting the images. Here is a screenshot of my setup:

Software setup for receiving NOAA 19. Left the SDR# tuned at 137.1 MHz using the RTL Dongle, right top the WXtoImg  to decode the image, and right bottom orbitron for tracking the satellite.
Software setup for receiving NOAA 19. Left the SDR# tuned at 137.1 MHz using the RTL Dongle, right top the WXtoImg
to decode the image and right bottom orbitron for tracking the satellite.

After the first reception, the WXtoImg converts the APT signal to images. Here are two examples of the pictures received:

Raw reception 26 of May 2015 of NOAA 19. Note the big cloud approaching from the left. On the right is the infrared version of the picture.
Raw reception 26 of May 2015 of NOAA 19. Note the big cloud approaching from the left. On the right is the infrared version of the picture.

APT weather image reception from NOAA 19.
Raw reception 24 (?) of May 2015 of NOAA 19.
After the first reception, WXtoImg makes some processing on the pictures to improve the contrast. Here is the output of raw images:

Improved contrast of NOAA 19 APT image. Received using RTL dongle, SDR# and WXtoImg.
Improved contrast of NOAA 19. Received using RTL dongle, SDR# and WXtoImg.

Improved contrast APT image received from NOAA 19 using the cheap solution for Software Defined Radio (SDR)
Improved contrast of NOAA 19.
After that, WXtoImg can also create a color version of the picture:

Color view of  the received APT image from the NOAA 19 using SDR# and WXtoImg.
Color view of the received image from the NOAA 19 using SDR# and WXtoImg.
Next target is to buy a proper antenna and a proper receiver, such as the  SDR play or the FUNcube Dongle plus.

Recent advancements in the RTL dongles packaging made affordable wide band receivers such as the  SDR Blog Receiver with Rtl2832u ADC Chip.

Thursday, June 4, 2015

Filerimos - Rhodes

Filerimos is a hill situated near the village of Ialyssos which stands on the same site as the Doric city of Ialysos, in ancient times. When the Dorians arrived around 1100 BC Ialysos became member of the alliance known as the Dorian Hextapolis. Excavations discovered a Mycenaean pottery, a Doric foundation and a Hellenistic temple of Athena. In the middle age the Knights of St. John used the site.  Remnants of these periods and lot of the successive conquerors can still be seen. On the way up the ancient road to the Acropolis, you see the foundations of the temple of Zeus and Athena. On top you'll find the beautiful Monastery. This Monastery was destroyed under, the Turks and rebuilt by the Italians who installed Capuchin monks in it.  A short and quiet walk leads to an enormous cross, accessible by a stairway to the top. Also there are everywhere peacocks.

Peacocks, peacocks everywhere!




The road to the big cross.

The cross it self. Actually you can see it when landing in the airport.

View from the cross.  Left the military airport, right the political "Diagoras".

Old medieval building.

It is the perfect place for peaceful walks.



Back entry of the monastery.

Inside monastery.



Inside Monastery.

Road to... monastery.

"What are you looking at?"

Sunday, May 31, 2015

Kallithea of Rhodes

The hot springs of Kallithea Baths in Rhodes is known since antiquity for its beneficial health red water that gushes from the rocks. Although not longer used, the visitors can admire the glamour of the magnificent Baths built by the Italians. Outside the high season, this is the favorite spot for local people looking for a quick swim. Most of the building are newly renovated and when i visited them some parts were under construction.


This is the main entry of the area of Kalithea springs. The baths are at the end of this picture.
This is the main entry of the area of Kalithea springs. The baths are at the end of this picture.

Paths that leads to the a number of building at higher ground.
  
View of the sea inside of the newly renovated buidlings.

Inside the buildings. You can see old pictures.


View of the back.




Some of the renovated paths.

Another path. Notice the details down.


Fisherman. View from the back.



Tuesday, May 26, 2015

Old town of Rhodes (Spring)

Some days ago i visited the old town of Rhodes again. The weather was perfect so i decided to take some pictures before the tourists arrived. These pictures taken around April.

 Old town: a merge of old building and new technology, but the result is not always beautiful.
Old town: a merge of old building and new technology, but the result is not always beautiful. 

A contrast of new and old building inside the old town. The window and the building in the center is in bad shape. In contrast the building on the right is newly renovated and although the owner used stone you can see the difference. Note also the road, the local authorities didn't have the money to fully repair it.
A contrast of new and old building inside the old town. The window and the building in the center is in bad shape. In contrast the building on the right is newly renovated and although the owner used stone you can see the difference. Note also the road, the local authorities didn't have the money to fully repair it.

Old Castle in the old medieval city of Rhodes, Greece.
Old Castle in the old medieval city of Rhodes, Greece.


Taverns, taverns, taverns everywhere! In old medieval city of Rhodes.
Taverns, taverns, taverns everywhere! In old medieval city of Rhodes.

Still beautiful empty streets inside the old medieval city in Rhodes, Greece
Still beautiful empty streets inside the old medieval city in Rhodes, Greece. Waiting for
the tourists. Sometimes i ask my self, why we don't  have tourists on Winter.