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I have been working on building a remote antenna switch to switch from my 40-10 meter to my 80-40 meter antenna —more on the switch in an upcoming blog post.

Humidity control is essential to make sure your home is healthy and comfortable.

At home, I wanted to install lights along the fence to create an ambiance in my backyard.

When I build or install a new antenna, I always run a series of tests.

With the Covid-19 shelter in place, I have decided to make my bread again.

I live in the middle of Silicon Valley in a suburban setting with small front and back yards.

Note This article was also posted on the San Mateo Radio Club monthly news letter.

If you are a new ham checking into a repeater or someone listening to the ham radio band with a scanner, you will discover a lot of the jargon.

In my last article, I wrote about working DMR+ using the DMRGateway module of your Pi-Star hotspot.

When it comes to DMR, especially in North America, people think of BrandMeister.

I am sure a lot of you have seen the History Channel show, Ice Road Truckers.

I wrote a little python program to send my iGate telemetry through APRS.

Tech day in Sacramento This Friday, I was invited to Sacramento to give my presentation on common mode current, what it is, and how to block or prevent it using common mode chokes.

I needed to remove some RF noise from an air filter in the next room.

A couple of weeks ago I got a new D-Star mobile radio.

A couple of months ago I designed a convenient Battery Monitor board with a voltmeter, one Andeson PowerPole connector as well as a USB power connector.

Note This article was originally posted in 2019.

Yaesu FT-70D The Pi-Star has the capability of working across digital modes.

Since I got my ham radio license, I have participated in Field Day with the PAARA1 radio club in Palo Alto.

In a previous article I describe how I built a mobile Allstar node.

The FT-70D is a great little radio that I always recommend for new hams as well as for experienced hams who want to try digital voice.

I often use small 7 or 9 Ah lead acid batteries because they are convenient and inexpensive.

One of the useful tools a ham radio operator can easily and cheaply build is a clamp-on RF current probe.

AllStar is a network of analog repeaters or nodes linked through the internet.

To work simplex with your DMR or C4FM radio please do not use the FM analog national call frequencies 2m (146.520 MHz) or 70cm (446.000 MHz).

Parachute mobile is all about the fun of jumping off a perfectly working airplane and share our thrill with our ham friends.

At Parachute mobile we like to tinker with things.

Many developers often use print statements for debugging their code.

Today we chartered a Catalina Capri 22 and went sailing in the sheltered waters off Santa Barbara.

If re like me, you might find it difficult to come up with a new password every time a website or an app asks you to create an account or change your password.

GIT Logo Git is a distributed version control system supporting non linear workflows, that focuses on speed and data integrity.

Every one knows the special file __init__.py.

The cpio(1) name is derived from CoPy In and Out.

Most Python books or blog posts, teach us that concatenating strings using the + sign is a bad idea.

All the motorcycle magazines are praising about the KTM Adventure 1190, for all it's new features and look compared to the previous models.

Python descriptors have been around for a long time, but probably because of the lack of good documentation they are still not widely used nor understood.

For some time now system administrators have known that password authentication has its shortcomings.

A simple way to access data from a file or from a database is to read each line or row, then assign each value to a list or a tuple.

Python like many other dynamic programming languages can be extended.

Why choose to use a public DNS Server The DNS is an essential part of the internet, it translates hostnames such as 0x9900.com into IP addresses 149.20.56.139.

For some of my projects such as DNS/DHCP servers, routers, firewalls, NTP Servers, or for some Arduino projects, I embed OpenBSD on small footprint and low power consumption machines.

1xx informational 100 Client should continue with request 101 Server is switching protocols 102 Server has received and is processing the request 103 resume aborted PUT or POST requests 104 Connection reset by peer the closing a socket result in a RST rat…

Spam is the most annoying thing I have to deal with every day on my servers.

Everyone knows that filenames and variables can contain spaces, but when it comes to writing a shell script most of the shell developers seem eager to forget that fact and write scripts that do not safely handle filenames containing spaces.

When writing code it's important to make sure all the variables are defined.

Alix PCEngine At home I have two networks, one for my family and me and one for my guests.

Wyse WinTerm You can build a highly accurate Stratum-1 NTP Server for less than $100 using an old Wyse WinTerm (see picture), a GPS and a few electronic components.

Everybody thinks SSDs are lightning fast.

This project will show the temperature in C and % of relative humidity of the ambiant air on an LCD display.

One of the tasks of system administrators is to secure the machines inside of their network.