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Getting Started, RaspberryPi, APRS, Xastir Part 2

April 20, 2018 Leave a comment

Let’s get our geek on girls.

So you got your RaspberryPi, you installed the OS from your NOOBS SD card or manually, as per Part 1, now what? Well there are lots of great things you can do, but I’m going to help you set up APRS.

You will need

RaspberryPi with operating system installed.

Keyboard and mouse and HDMI screen and HDMI cable

A Terminal Node Controller such as  TNCPi, or a radio with a build in TNC, like the Kenwood TM-D700 series and a suitable cable to connect your TNC to the pi if the TNC is not an add on board, commonly referred to as a hat.

APRS, variously known by a few names is an Automatic Packet Reporting System, commonly used to show locations of objects and for messaging, typically on VHF and UHF but also HF. You can see APRS in action by entering the name of your city into the search box at www.aprs.fi. You can adjust the time span to see movement of the various objects over a span of time. Below is my city of Sydney (VK2) for the previous 24 hours. That moving house is a worry 🙂

Screen Shot 2018-04-21 at 08.55.30.png

APRS can also be used to show and share weather at your location by integrating your APRS with your weather station should you have one. I will explore that topic later.

Here is my weather station on APRS

Screen Shot 2018-04-21 at 08.59.24.png

So let’s get started

Your raspberryPi is turned on, connected to mouse, keyboard and an HDMI screen.

Open up the terminal, remember it is the black icon >_ or use the keystrokes mentioned in Part 1 Cntrl-Alt-T.

Into terminal type the following, one line at a time- ignore lines preceded with #, these are my comments

# You should always update before installing new software

sudo apt-get update

# install the xastir package
# hit ‘Y’ when prompted – it installs lots of dependencies
# so will take some time

sudo apt-get install xastir

# now start X-windows if you’re not already in the graphic user interface

startx

Once you have xastir installed and X running, you will find xastir listed under internet on the newer versions of the OS– alternatively open up a terminal window and start the program by typing xastir.

You will be prompted for your callsign and location etc. – this is fairly self explanatory but the xastir website will be able to help. One thing I will say is that the first thing you’re likely to want is a better map – go Map > Map Chooser, select the four Online/OSM_cloudmade_3.geo maps for Open Streetmap, and deselct the default worldhi.map. It will take a bit of time for the maps to be downloaded but they’re very good. You will also need to know your latitude and longitude in degrees and decimal minutes not degrees minutes and seconds or have a GPS connected as well (more on that later). You can find your lat/lon on Google maps with a right click on your location. You can convert to various d,m,s decimal degrees etc at many conversion sites like https://www.directionsmag.com/site/latlong-converter/

Connecting a Terminal Node Controller (TNC) 

There are many TNCs available but I use a Kenwood TM-D700. It and the D710 have a built in TNC. Follow the radio manual instructions and set the TNC to serial, not KISS.

If you are using another TNC, follow the instructions to connect it to the Pi and to set it to serial TNC mode.

We will explore other TNCs in Part 3.

For those TNCs connected by USB, you will need a cable to connect to the USB port on the Pi. You will definitely need a special programming/serial cable to connect your D700 series radio. Don’t fool around with serial USB converters they will not work, Use this cable if you have a D700 series radio. It is the only one that I have found that works with the Kenwood radios

So let’s get data coming in from our TNC.

First connect your cable to both TNC and Pi. Find the USB port that it is connected to with this command in terminal

dmesg | grep tty

#That | key is hard to find on some keyboards.
#On my Apple keyboard it is on the far right and requires shift. :-).

You should see something like this

Screen Shot 2018-04-21 at 09.33.49

Note the second last line – My FTDI cable is ttyUSB0, yours may be different.

Now go to Xastir  Interface > Interface Control and click ‘Add’. Select ‘Serial TNC’, set /dev/ttyUSB0 as the port or whatever you found yours was with the dmesg command, change the baud rate to 9600 and leave the rest as default for now, although you might want to change tnc-startup.sys for one matching your TNC from the list in /usr/share/xastir/config. Mine is tnc-startupD700.sys

Click ‘OK’ and hopefully, you’ll be able to select your new interface and start it – ‘DOWN’ will change to ‘UP.

For debugging, View > Incoming Data provides some very useful insight into data flowing to and from the TNC or other interfaces.

If you want to receive data from the Internet, add an ‘Internet Server’ interface. You’ll need to get a passcode to match your callsign (google APRS passcode generator for clues,) and find your most convenient aprs host and port. Again, the ‘Incoming Data’ window can help with debugging. My aprs server is first.aprs.net.au. Take a look here for yours http://www.aprs-is.net/aprsservers.aspx

At this point, consult existing XASTIR resources to refine your configuration. Good luck!

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Categories: Uncategorized

Getting Started RaspberryPi, APRS, Xastir Part 1

April 13, 2018 2 comments

Screen Shot 2018-04-14 at 08.42.03.png

This blog post is intended for hams beginning with RaspberryPi, who want a great ham radio project. It was initiated by a query on the YL Op Net a women’s only net that happens 0000 utc Fridays on the ALARA Conference Server.

The first thing you need to do is get yourself a Raspberrypi. If you are brand new to RaspberryPI you may wish to buy all of the bits and pieces you need straight up as that is often the cheapest option, unless you have some stuff laying around, like keyboards and mouse and HDMI monitor or TV. There are some great complete kits on eBay and elsewhere.

While you are at it, why not get the preinstalled operating system on an SD card and save yourself the process of setting up your own SD card. This is a good idea until you get more familiar with the pi. Otherwise you need SD card formatting software and a range of other tools and a fast SD card. The RaspberryPi 3 uses micro SD whereas the earlier models use normal SD cards. The prepackaged OS install is called NOOBS. If you want to go it alone, try this resource for a how to

https://www.raspberrypi.org/documentation/installation/noobs.md

To get started with RaspberryPi, one of the best things you can do is find a likeminded group of people either physically located near you or via social media. Most RaspberryPi’s are initially setup to run a Linux operating system called Raspian. If you have not ever used command line interface or Linux before, it will be very useful to have some help on hand, as it can be daunting initially. The new operating system on the RaspberryPi has a great Graphic User Interface (GUI) but because of the inability to log in as root and for other reasons of convenience, you will do most to your work in the command line. Command line looks like this-

Screen Shot 2018-04-14 at 08.11.05

The above is a great example because one of the first commands you will need to know is sudo. Think of it as “superuser do.” When you log in to a pi as you can see from the above image, you are logged in as pi. eg. pi@raspberrypi. Now the user named pi is not a superuser, not an administrator, probably so we can’t mess things up too much. So if you want to do something like install or remove software or update the system, you have to tell the pi that you wish to do that as a superuser, hence sudo. You will quickly get used to preceding most commands with sudo.

Plug your keyboard and mouse and HDMI cable connected to a screen in and turn the screen on- you can use a television. Put the SD card in the pi and connect the power. There is no on/off switch. I am going to assume you have access to a HDMI cable and a monitor, otherwise you have to run the pi headless which I will describe later. When you get your pi and start it up, if you are using the latest version of the operating system, it will load the GUI. Do not connect power hungry devices to the USB- you will need a powered hub if you do.

You will need to access the command line interface, which you do by opening  the terminal. Click on the black icon with this symbol >_ in the top menu bar or type Ctr+Alt+T.  The very first thing you need to do before you do anything else is update and upgrade the software that is installed. So you will get to use the command line straight up. Later on when you are running headless, you could  copy and paste  from this blog and save some time, but for now, just type the following commands

sudo apt-get update

Then wait for the pi to complete the tasks and select y or yes if asked.  Then type

sudo apt-get upgrade

This one will take quite a bit longer to run and will require interaction.

Now you should be ready to get started with installing Xastir. Bear in mind that this blog will describe using Xastir connected to a Kenwood TM-D700 which has a built in Terminal Node Controller, (TNC) If your radio does not have a built in TNC, you will need to get one. There are a few made especially for the RaspberryPi, like this one.

73

de VK2KIM

 

 

 

 

 

 

Categories: Uncategorized

Inspirational YLs

February 20, 2018 Leave a comment

Are you looking for ways to inspire young women to be involved in science and amateur radio? These inspirational women may be the answer.

Female Space Hams

 

https://en.wikipedia.org/wiki/Tamara_E._Jernigan

Tamara E. Jernigan (USA) formerly KC5MGF. Jernigan attended Santa Fe High School in Santa Fe Springs, CA. She graduated in 1977. Jernigan attended Stanford University, where she earned a B.S. degree in physics in 1981, an M.S. in engineering science in 1983. At the University of California, Berkeley, she received an M.S. in astronomy in 1985. In 1988 she was awarded a Ph.D. in space physics and astronomy from Rice University.

She entered the NASA Astronaut Corps in 1986 and retired in 2001. Her first trip to space was on June 5, 1991.[1] She flew on five Space Shuttle program missions (three on Columbia and one each on Endeavour and Discovery) and logged 1512 hours in space. In her last mission on Discovery in 1999, she performed an extra-vehicular activity for 7 hours and 55 minutes.

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http://www.spacefacts.de/bios/international/english/bruemmer_renate.htm

Renata Luise Bruemer (Germany) DB5PL Studied mathematics and physics at the Munich University; Ph.D. in meteorology from University of Miami, Florida, 1986; research scientist at University Corporation for Atmospheric Research, Boulder, Colorado; was selected as backup for STS-55 (D-2 mission).

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https://en.wikipedia.org/wiki/Yvonne_Cagle

Born in West Point, New York, Yvonne Cagle (USA) formerly KC5ZSV graduated from Novato High School in Novato, California. She received her bachelor’s degree in biochemistry from San Francisco State University in 1981, and a doctor of medicine degree from the University of Washington in 1985. She completed a transitional internship at Highland General Hospital in Oakland, California in 1985 and received a certificate in Aerospace Medicine from the School of Aerospace Medicine at Brooks Air Force Base, Texas, in 1988. She then went on to complete a residency in family practice at Ghent FP at Eastern Virginia Medical School in 1992 and received certification as a senior aviation medical examiner from the Federal Aviation Administration in 1995.

Cagle retired from the United States Air Force with the rank of Colonel in 2008. As a commissioned medical officer in the USAF Cagle served as Air Force Medical Liaison Officer for STS-30, before she became a NASA astronaut. She worked as medical doctor at NASA’s Occupational Health Clinic from 1994 to 1996. In 1996 she was selected for astronaut training by NASA.

Yvonne Cagle was a member of the Astronaut Class of 1996 (NASA Astronaut Group 16). She is currently assigned to Johnson Space Center’s Space and Life Sciences Directorate.

Dr. Cagle is also an advisor for NASA’s Flight Opportunities Program (originally named CRuSR – Commercial Reusable Suborbital Research Program). Currently Dr. Cagle is on faculty and serves as the NASA liaison for exploration and space development with Singularity University. During the workshop, Dr. Cagle was embedded with the crew as a crew training consultant and advisor, providing insights and feedback to both crew and study team from the viewpoint of an astronaut, flight surgeon, space development expert, and science liaison.

She has recently been selected reserve crew for Hawai‘i Space Exploration Analog and Simulation (HI-SEAS), which is part of a study for NASA to determine the best way to keep astronauts well nourished during multiple-year missions to Mars or the moon. Furthermore, Dr. Cagle is also listed as an honorary member of the Danish Astronautical Society.

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https://en.wikipedia.org/wiki/Tracy_Caldwell_Dyson

Tracy Caldwell Dyson (USA) KF5DBF  born Tracy Ellen Caldwell; August 14, 1969 is an American chemist and NASA astronaut. Caldwell Dyson was a Mission Specialist on Space Shuttle Endeavour flight STS-118 in August 2007. She was part of the Expedition 24 crew on the International Space Station between April 4, 2010 and September 25, 2010. She has completed three spacewalks, logging more than 22 hrs of EVA including work to replace a malfunctioning coolant pump.

As an undergraduate researcher at the California State University, Fullerton (CSUF), Caldwell Dyson designed, constructed and implemented electronics and hardware associated with a laser-ionization, time-of-flight mass spectrometer for studying atmospherically relevant gas-phase chemistry.

Also at CSUF, she worked for the Research and Instructional Safety Office as a lab assistant performing environmental monitoring of laboratories using hazardous chemicals and radioactive materials, as well as calibrating survey instruments and helping to process chemical and radioactive waste. During that time (and for many years prior) she also worked as an electrician/inside wireman for her father’s electrical contracting company doing commercial and light industrial type construction.

At the University of California, Davis, Caldwell Dyson taught general chemistry laboratory and began her graduate research. Her dissertation work focused on investigating molecular-level surface reactivity and kinetics of metal surfaces using electron spectroscopylaser desorption, and Fourier transform mass spectrometry techniques. She also designed and built peripheral components for a variable temperature, ultra-high vacuum scanning tunneling microscopy system.

In 1997, Caldwell Dyson received the Camille and Henry Drefus Postdoctoral Fellowship in Environmental Science to study atmospheric chemistry at the University of California, Irvine. There she investigated reactivity and kinetics of atmospherically relevant systems using atmospheric pressure ionization mass spectrometry, Fourier transform infrared and ultraviolet absorption spectroscopies. In addition, she developed methods of chemical ionization for spectral interpretation of trace compounds. Caldwell Dyson has published and presented her work in numerous papers at technical conferences and in scientific journals.

Selected by NASA in June 1998, Caldwell Dyson reported for training in August 1998. Her Astronaut Candidate Training included orientation briefings and tours, numerous scientific and technical briefings, intensive instruction in Shuttle and International Space Station (ISS) systems, physiological training, ground school to prepare for T-38 flight training, as well as learning water and wilderness survival techniques. Completion of this training and evaluation qualified her for flight assignment as a mission specialist.

In 1999, Caldwell Dyson was assigned to the Astronaut Office ISS Operations Branch as a Russian Crusader, participating in the testing and integration of Russian hardware and software products developed for ISS. In 2000, she was assigned prime Crew Support Astronaut for the ISS Expedition 5 crew, serving as their representative on technical and operational issues throughout the training and on-orbit phase of their mission.

During ISS Expeditions 4 through 6, Caldwell Dyson also served as an ISS spacecraft communicator (CAPCOM) inside Mission Control. In 2003, she made a transition to the Astronaut Shuttle Operations Branch and was assigned to flight software verification in the Shuttle Avionics Integration Laboratory (SAIL) and also worked supporting launch and landing operations at Kennedy Space Center, Florida. Caldwell Dyson also served as Lead CAPCOM for Expedition 11.

Caldwell Dyson was assigned to, and later flew on STS-118, Space Shuttle Endeavour, on August 8–21, 2007, which was the 119th space shuttle flight, the 22nd flight to the station, and the 20th flight for Endeavour. Caldwell Dyson was assigned as Mission Specialist #1 on this flight. During the mission Endeavour’s crew successfully added another truss segment, a new gyroscope and external spare parts platform to the International Space Station. A new system that enables docked shuttles to draw electrical power from the station to extend visits to the outpost was activated successfully. A total of four spacewalks (EVAs) were performed by three crew members. Endeavour carried some 5,000 pounds of equipment and supplies to the station and returned to Earth with some 4,000 pounds of hardware and no longer needed equipment. Traveling 5.3 million miles in space, the STS-118 mission was completed in 12 days, 17 hours, 55 minutes and 34 seconds. Finally, during the flight of STS-118, Caldwell Dyson celebrated her 38th birthday in space.

On April 4, 2010, Caldwell Dyson joined the Expedition 23 crew aboard ISS. She lifted off on April 2, 2010 from the Baikonur spaceport aboard a Russian Soyuz capsule (Soyuz TMA-18). After 176 days duty as part of the Expedition 24 crew, she returned to Earth with the Soyuz TMA-18 landing unit. Together with commander Aleksandr Skvortsov and flight engineer Mikhail Korniyenko, Dyson landed in Kazakhstan on September 25, 2010.

In a television interview on the 40th anniversary of the first moon landing, she said she is the first astronaut who was born after Apollo 11.

As Tracy Dyson, she is the host of a series on NASA TV called “StationLife”, which focuses on facets of life aboard the International Space Station.

She appeared on Episode 3 of MasterChef Junior Season 4.

On March 21, 2017, Dyson stood behind President Trump as he signed a bill for NASA to send humans to Mars in 2030s and receive $19.5 billion in 2018 funding. Dyson and fellow NASA astronaut Chris Cassidy presented Trump with an official flight jacket during the ceremony.


 

You can read about many more inspiring female astronauts who were hams at the following links

https://en.wikipedia.org/wiki/Catherine_Coleman

https://en.wikipedia.org/wiki/Eileen_Collins

https://en.wikipedia.org/wiki/Samantha_Cristoforetti

https://en.wikipedia.org/wiki/Nancy_J._Currie-Gregg

https://www.jsc.nasa.gov/Bios/htmlbios/dunbar.html

https://www.nasa.gov/astronauts/biographies/jeanette-j-epps/biography

https://www.jsc.nasa.gov/Bios/htmlbios/godwin.html

https://www.jsc.nasa.gov/Bios/htmlbios/helms.html

https://en.wikipedia.org/wiki/Yelena_Kondakova

https://www.jsc.nasa.gov/Bios/htmlbios/lawrence.html

https://en.wikipedia.org/wiki/Sandra_Magnus

https://www.jsc.nasa.gov/Bios/htmlbios/metcalf-lindenburger-dm.html

https://en.wikipedia.org/wiki/Barbara_Morgan

https://en.wikipedia.org/wiki/Lisa_Nowak

https://www.nasa.gov/centers/johnson/about/people/orgs/bios/ochoa.html

https://en.wikipedia.org/wiki/Kathleen_Rubins

https://en.wikipedia.org/wiki/Yelena_Serova

http://www.esa.int/About_Us/Welcome_to_ESA/ESA_history/50_years_of_humans_in_space/Dr_Helen_Sharman

https://en.wikipedia.org/wiki/Heidemarie_Stefanyshyn-Piper

https://en.wikipedia.org/wiki/Kathryn_D._Sullivan

https://en.wikipedia.org/wiki/Janice_E._Voss

https://en.wikipedia.org/wiki/Peggy_Whitson

https://en.wikipedia.org/wiki/Sunita_Williams

https://www.nasa.gov/astronauts/biographies/stephanie-d-wilson/

Categories: Uncategorized

KRK VXT6 Repair

February 6, 2018 2 comments

Some time ago I picked up a powered studio monitor for about $20. The music store was closing down and the speaker had a fault- the tweeter wasn’t working. These studio monitors of this size range in price from about $200 to $400, so I couldn’t pass up the deal, as I was sure I could repair it – one day.

That day finally arrived. I had purchased a spare tweeter which had sat in the parcel unopened for some time. When I unpacked it, you guessed it, it was the wrong part. Given that it had come from the US, the return postage added way too much to the cost of repair, so I decided to repair the existing tweeter.

20180206_134528

There isn’t much to a permanent magnet tweeter, basically the only electrical component in it is a super-fine winding of copper. This usually fails to due physical stress or sometimes an over-voltage or over-current fault. All that is required is to solder the broken wire- easy right? Well the wire is quite a bit thinner than a human hair and enamelled and wound very tightly into a place that is difficult to get to. You got the picture?

20180206_134524

The good story is that after one repair, a subsequent failure and another repair, the speaker works great

 

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My Dad’s 1935 Ultimate Receiver Part 1

January 23, 2018 Leave a comment

Some time back in 2015 I obtained a 1935 Ultimate AU Receiver. I had just recently restored a 1936 Pilot receiver and was keen to do the same for this radio. What I most liked about the radio was that its “birth year” was the same as my Dad’s. Dad’s 80th birthday was forthcoming and I thought that the radio would make the ultimate present. He and my Mum had been loaned a console radio early in their marriage and I know they loved it and were disappointed to see it return to the owner, many years later.

thumbnail_RL AU 34 pix 2

I set about doing as much restoration as I could before my Dad’s birthday, which was to be soon. Unfortunately it was during the worst part of my life, when my gender disphoria had resulted in serious mental health issues and the loss of all that was dear to me. I rushed to get the radio ready for the birthday celebration while dealing with my own demons. One capacitor proved difficult to obtain- a filter capacitor across the DC output of the rectifier, so I left the original there. I left the radio running for many hours as a test and it worked a treat.

When I presented the radio to my Dad, on the day after his birthday, it immediately failed with a loud pop. I left it with him, with the view to getting back to it “one day.” BTW he loved it.

However my life was about to take a radically different path and it would be some time before I saw the radio and indeed my Dad again…… More in Part 2

Categories: Uncategorized

A Different Project- An Audio Amp

August 26, 2017 2 comments

A friend of mine contacted me to ask if I knew someone who could trouble-shoot her valve driven audio amplifier- of course I said I could. The amplifier is an interesting Chinese brand, a Yaquin MC-100B. It can be used in two different modes Ultra-linear or Triode mode. The amp uses a bunch of valves including 2x 12AX7 a pretty common  amplifier found in everything from guitar amps to radios, used in this case as voltage amplifiers. It also uses 4x 6N8P as drivers and cathode followers and finally 4x KT88 valves in the output stage.

My friend complained that the amp had not worked for nearly 12 months but the filaments on all valves glowed. According to her tests, it had no output at all. She dropped it off and I promised to take a good look at it. Since I was lacking any means to connect any kind of music source to it, I got straight down to visual fault finding- a mistake but only a minor one- it simply cost me some time. I was later to find that when I did connect it to a source it worked, though not perfectly.

I began by removing the bottom plate and visually inspecting all components and PC boards for damage, burns, broken tracks, anything obvious- there was nothing. I then began checking all voltages at the appropriate test points. Beware if you are attempting to do the same. There are some KILLER voltages in here; some over 1000V AC. Beware!

I found all to be within specification. I at this time did not check the bias as I wanted to first confirm the amp had no output at all. I connected my audio signal generator to the audio inputs on the front of the amp (labelled 0.6V). I configured the amp switches appropriately for these inputs and connected some speakers. I immediately heard a pretty good tone, so the amp did have output after all. I confirmed with my friend that she had not just inadvertently had the inputs configured wrong, but she advised she had tested all configurations. hmmmmmm …some testing at her place may be necessary to check that the audio source is not the issue.

Continuing with my testing I noticed that one channel was lower output than the other. I began by checking all bias voltages, finding all of them low but one non-existant. I swapped the suspected KT88 with one of the good ones and the bias voltage returned- indicating a failed tube. I then set about adjusting the bias voltages to 0.55V as specified. Even with one channel low, the amp sounds pretty good.

I instructed my friend to purchase her choice of new KT88 or a matched set of four. This amp is not very sensitive to valve changes, so I would just purchase one. I finished up the repair with fixing the cage over the valves, as it had begun to come apart.

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I Need to Restore Before I Restore

July 31, 2017 Leave a comment

Today I began preparing a list of parts required to restore my Echopone EC-1, and familiarizing myself with the alignment procedure. I also made a list of parts required to interface the test equipment with the radio.  It was at this point that I realized things would be a whole lot simpler if I used a Vacuum Tube Voltmeter for the RF alignment. While I can use my signal generator and my oscilloscope for the IF alignment, I liked the simplicity of using a VTVM for the RF alignment.

There is only one problem. I have a habit of purchasing vintage test equipment that needs restoring, for example my capacitance tester and other items. So it is with my VTVM which is a Heathkit V-5. Made in 1952, the V-5 like all electronics of that era, uses wax and paper capacitors. These capacitors will almost certainly have failed or will fail if I power the unit. So it is that I added to the list of parts, two capacitors required to restore the V-5. Of course it won;t be as simple as replacing the capacitors- I will have to check all resistors and calibrate the unit as well as make a probe for it. But the beauty is, I will have a working VTVM that like my radios is from an earlier time.

 

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