Posts published by: Luke

rtl tcp radio on iPad, part 3

A quick review on this project: the goal is to write a program for pythonista, on the iPad, that can stream IQ samples from a remote SDR via rtl_tcp, running on the remote computer ("quantalinux"). I wanted to start simple, so I first created a working flow graph in GNU ...

A Useful Windows Tool

Recently at work, I was given a task that involved a lot of data analysis; specifically, curve fitting. A lot of data was collected, and it needed to be fitted to the predictions to check agreement. Normally something like this would be easy to automate for efficiency at the Linux ...

Today's NVIS

If you know what NVIS (Near Vertical Incidence Sky-wave) stands for, then you are probably a ham radio operator. It is a mode of propagation in which a radio wave is emitted skyward, and, if it is below a certain critical frequency, it will bounce off the ionosphere, and back ...

Santa Cruz, CA Rain Fall, 2014

I don't usually post on weather, but I have been especially interested,as many people in California, in the rain fall. There has been a pretty bad drought over the past few years, and people seem alarmed. I have been concerned, too; however, as an analysis of the previous ...

Man-Cave Temperature: Rasperry Pi and DS1820

Yesterday, I was able to complete a fun little project. It was perfect, as it required very little time (only a few hours). This was enough to finish it while the family was out and about. Here is a rough outline of the steps I took:

Materials required:
1. DS1820 ...

SSH Permissions

I recently described the process I went through in getting my raspberry pi to serve a statically generated page, using wget on my Linux desktop running WordPress. I wrote a script to use "rsync" over ssh, but I ran into an issue: the key pair (so I could transfer without ...

Household Power Usage with the Kill-A-Watt

I just performed a rather interesting exercise in data collection – I measured the annual cost of running various household appliances, assuming they are on all the time. Heaters, used in the winter, were by far the most expensive. For runner up, TVs and computers were the next most expensive. See ...

Artificial Lawn: Before and After

We recently decided to get an artificial lawn in our front yard.  Here are the before and after pictures:

before

Before

after

After

As you can see, the transformation was amazing.  It was a bit heavy on the budget, but it was completely worth it!  We are very happy with it.  As ...

Built Front Yard Gate

Last summer, I mostly finished building a fence around my property.  This summer, I will finish it the rest of the way.  One of the things left to do was build a gate in our front yard.

Gate needed. New fence to left, old fence to right.

Gate needed. New fence to left, old fence to right.

As you can ...

How to Hang a Dipole Antenna

I recently purchased a W8AMZ 80-6M OCF dipole.  It works pretty well, but performance varies depending on the installation.  More on performance in a later post; for now, I will discuss how I installed this antenna using my 50# recurve bow.  Needless to say, this post assumes that you know ...

Booting Raspberry Pi from USB drive

The Raspberry Pi has been a bit slow running WordPress.  I read, however, that it can be made faster by running off of a USB stick.  This has been dealt with quite well from a few other sites, so I will not go into detail with it.  I will list ...

Useful tip of the day: Viewing Windows Event Logs

Occasionally, I have the need to log into work and perform tasks from home.  I don't take always take the time to log my hours, and remembering can be a pain.  I discovered how to check the windows event logs, and they give me an accurate idea of the ...

Insufficient Memory Errors

In a previousblog, I discussed how to set up WordPress from a home-hosted computer, so that it could be edited from within the LAN.

​1. For the desktop computers, editing the hosts file was necessary so that the theme being used on the blog could be visible from within ...

Best BASH Profile

The best BASH profile additions ever. I created a working copy with everything below. You can easily implement the following addons with the following (if you are root):

cd /etc/profile.d
wget lukesnow.net/lukes_addons.sh

With this approach, these addons will be available for all users on the ...

Radio install complete!

I just finished installing my new aftermarket radio, the DEH-X4600BT.  Originally, all I wanted was a radio that had an auxiliary jack (3.5mm).  Seems like old technology, but surprisingly I hadn't seen many radios with it.  So I started looking, and found that the current technology in aftermarket ...

Preparing for Radio install.

maxwell_radio_harness

This is my cat.  His name is Maxwell (as in James Clerk Maxwell).  He is cool, he kills stuff.  He eats it too.

Below this vicious killer, you will see that there is a nice, homemade wiring harness.  The black piece to the left is the part that plugs into ...

Fixed the oven!

Today, I fixed our gas oven.  Here is the symptoms we were seeing:

​0. The oven would only partially warm up.

​1. The oven wouldn't turn on reliably.

​2. If we re-plugged it in, it would sometimes work.

After some googling ("gas oven won't warm up all the ...