cannikin

rtl_fm, a simple narrow band FM demodulator for RTL2832 based DVB-T receivers

Use:	rtl_fm -f freq [-options] [filename]
	-f frequency_to_tune_to [Hz]
	    use multiple -f for scanning (requires squelch)
	    ranges supported, -f 118M:137M:25k
	[-M modulation (default: fm)]
	    fm, wbfm, raw, am, usb, lsb
	    wbfm == -M fm -s 170k -o 4 -A fast -r 32k -l 0 -E deemp
	    raw mode outputs 2x16 bit IQ pairs

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pi@picluster1 ~ $ sudo rtl_fm -f 441M -M wbfm -s 100000 -r 48000 -l 80 - | aplay -r 48k -f S16_LE
Found 1 device(s):
  0:  Realtek, RTL2838UHIDIR, SN: 00000001

Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
Tuner gain set to automatic.
Tuned to 441291000 Hz.
Oversampling input by: 11x.
Oversampling output by: 1x.

cannikin

# app/views/posts/show.html.erb
<article id="post-<%= @post.id %>" class="post">
  <h1><%= @post.title %></h1>
  <%= @post.body %>
  <small><%= @post.author %></small>
  <section class="comments">
    <h2>Comments</h2>
    <%= render @post.comments %>
  </section>
</article>

cannikin

#!/bin/sh

FILES='(js|css|rb|haml|erb)'
FORBIDDEN='(binding.pry|console.|debugger)'
GREP_COLOR='4;5;37;41'

if [[ $(git diff --cached --name-only | grep -E $FILES) ]]; then
  git diff --cached --name-only | grep -E $FILES | \
  xargs grep --color --with-filename -n -E $FORBIDDEN && \
  printf "\nLooks like you are trying to commit something you shouldn't.  Please fix your diff, or run 'git commit --no-verify' to skip this check, if you must." && \

cannikin

Typical Ruby on Rails AWS Server Setup

You should be able to start a fresh EC2 instance of Ubuntu and follow the instructions below to get a server with your preferred version of Ruby, nginx ready to delegate requests to Unicorn, and logrotate setup to keep your disk from filling up with log files. You will also have ruby-install for installing new rubies and chruby for switching between them. A .ruby-version file will be added to the home directory of the user that runs this script.

Install

0. Start an EC2 instance using the latest Ubuntu image (as of 2015-06-18 ami-5189a661 for EBS, 64-bit SSD)
1. Copy the config files below into /tmp using the file names specified in the title.
2. Edit /tmp/setup.sh and change the variables at the top to match your setup
3. Make /tmp/setup.sh executable: chmod +x /tmp/setup.sh

cannikin

positron-2:cal_counter_grape rob$ rake jasmine:ci
[2015-04-07 11:33:05] INFO  WEBrick 1.3.1
[2015-04-07 11:33:05] INFO  ruby 2.2.1 (2015-02-26) [x86_64-darwin14]
[2015-04-07 11:33:05] INFO  WEBrick::HTTPServer#start: pid=21195 port=59830
Waiting for jasmine server on 59830...
jasmine server started.
F
Failures:
          Entries sorts entries by ate_at, newest first

cannikin

# Procedure
#
# From a completely fresh restart, ssh'd into the Pi from my mac and then ran the 
# sysbench command listed at the top of each section. Copied and pasted the
# output, restarted, and ran the next.
#
# 1000MHz overclock settings:
#
# arm_freq=1000
# sdram_freq=500

cannikin

require 'elasticsearch'
require 'optparse'

client = Elasticsearch::Client.new :host => 'localhost:9200'
indices = client.cat.indices.split("\n").collect { |i| i.split(' ')[1] }

indices.each do |index|
  if index =~ /\.marvel/
    client.indices.delete :index => index
    puts "Deleting #{index}"

cannikin

- cache [@user, @user.posts] do
  = @user.inspect
  - @user.posts.each do |post|
    - cache post do
      = post.inspect

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%h1 Heading 2

:javascript
  console.info
  
%h2 Heading 2