Tag Archives: VHF/UHF

Activities, Antennas, Featured, General, Newsletter, Space, Station Equipment

A Portable Satellite Station Part 1 – A Simple Station for AO-85

Our club has quite a few members who are interested in space communications. We decided to build a simple portable satellite station last year for our 2016 Field Day operation to learn about satellite communications and to create something new for folks to work with during 2016 Field Day.

Simple Portable Satellite Station
Simple Portable Satellite Station

Our 1.0 Portable Satellite Station was a relatively simple setup built around an HT, an Elk 2m/70cm satellite antenna, and some gear to improve the receive performance and transmit power output of the HT. All of the gear was mounted on a board to make it easy to transport and it is powered by a LIPO rechargeable battery. The gear in our 1.0 station is made up of the following:

Improved Portable Satellite Station Antenna Support
Improved Satellite Antenna Support

Our first contacts with our 1.0 station were made using the Elk Antenna hand-held. Later, we created a “plumber’s special” setup with a camera tripod to make pointing the antenna easier. Note the angle meter from a local hardware store which measures the elevation angle of the antenna.

AO-85 (Fox-1A) U/V Mode FM Cube Satellite
AO-85 (Fox-1A) U/V Mode FM Cube Satellite

This setup worked great for making FM contacts through AO-85 (Fox-1A), a  U/V mode FM EasySat. We used the 1.0 station on multiple occasions including Field Day 2016 and several of our club members used it to make their first satellite contacts. The Full-Duplex HT allowed us to hear our own signal coming back from the satellite which was an important tool to help with aiming the antenna properly. The ELK Dual-Band antenna is also a good choice because it uses a single feed point and a single polarization for both the 2m and 70cm bands.

Portable Satellite Station Team Operating Approach
1.0 Station Team Operating Approach

We used the team operating approach outlined above. This worked especially well for new folks who had not made a satellite contact before as it enabled each of the three team members involved in making the contact to focus on a specific part of the contact. We used orange plastic tent stakes to make AOS, Time of Closest Approach, and EOS to mark headings for each satellite pass. Small flashlights used at the stakes made them glow for night-time passes.

We certainly had a lot of fun with our 1.0 Satellite Station and I expect that we’ll continue to use it. As we gained a little experience with AO-85, we decided that we wanted to build a more capable Portable Satellite Station which we could use to operate with linear transponder satellites and which included a tracking system and better antennas. I know from experience with our home satellite station that DX contacts are possible using higher altitude linear transponder satellites like FO-29.

We would also like to be able to use APRS and other digital modes through satellites as well as receive SSTV pictures from space.

These goals have become the basis for building our Portable Satellite Station 2.0. More on the new station in Part 2 of this series. Other articles in the series include:

You may also be interested in the satellite station at our home QTH. You can read more about that here.

73,

Fred (AB1OC)

Featured, General, Newsletter, Space

First Amateur Radio Satellite in Geosynchronous Orbit in 2017?

Researchers at the Ted and Karyn Hume Center for National Security and Technology are preparing to send an amateur radio satellite into a geosynchronous orbit in 2017.

This will be a great opportunity for Amateur Radio satellite operators! Some preliminary information about this satellite may be found here.

The proposed frequency plan for the spacecraft is:
Uplinks: 5655-5665 MHz
Downlinks: 10455-10465 MHz

The amateur radio payload will comprise a Software Defined Transponder capable of supporting many different modes, including analog SSB.

 

Geosynchronous Amateur Radio Satellite Possible Orbit

Possible coverage of a Geosynchronous satellite at 74 degrees West – Credit NX5R

 

 

 

 

This satellite’s high altitude will create a very large coverage footprint. Also, see the following article on the ARRL website for more information.

According to AMSAT Vice President-Operations Drew Glasbrenner, KO4MA, the satellite’s potential footprint would extend over the US from the Mid-Pacific to Africa.

Source: First amateur radio in geosynchronous orbit will aid disaster communications

Activities, General, Newsletter, Space, Youth Activities

A High Altitude Balloon Project To Generate STEM Interest And Learning

Several members of our club have been working on a High Altitude Balloon Project to promote STEM interest and learning by young people. Our project team currently includes the following folks:

Other interested club members are welcome to join us.

We want to provide a STEM learning opportunity and project to be planned and executed by young people ages 10 – 16. We are actively seeking engagement and support from local schools, Scout Troops and other youth organizations to help us with this project.

Our goals for the project include:

  • Building and launching a high altitude balloon carrying Amateur Radio to near space and back
  • Enabling young people to plan and execute the project with help and guidance from members of the Nashua Area Radio Club and supporting adults from organizations that wish to assist us
  • Helping young people gain STEM-based experience and learnings by handling all phases of the project including:
    • Planning the flight, the balloon, and its payload
    • Building the balloon and testing it on the ground
    • Launching, tracking and recovering the balloon’s payload
    • Analysis of the flight data and the creation of a presentation to be delivered to fellow students and other interested groups

We plan to introduce new technology, experiments, and flight elements and develop team member skills and expertise across multiple launches. Later phases of the project are expected to include design and construction of additional payload electronics, high altitude/longer duration flights, and additional on-board atmospheric science experiments.

Typical High Altitude Balloon System
Typical High Altitude Balloon System

Our goals for the initial flight mission of this project will include:

  • Building a helium filled balloon which carries a payload of < 4 lbs. to altitudes in excess of 90,000 ft (27,400 m)
    • Parachute controls decent rate after balloon bursts
  • Capturing a video of flight using on-board GoPro video camera(s)
  • Flying an on-board APRS transmitter allows tracking from the ground via Amateur 2m APRS and aprs.fi
    • Flight computer plus APRS provides altitude, position and temperature data throughout the flight
    • Anyone with a device that has internet access and a web browser will be able to track the flight
  • Augmenting the APRS system with commercial satellite tracker to assure successful recovery of our payload by the project team
High Altitude Balloon
High Altitude Balloons

The balloon is filled with enough Helium to carry its payload to a target altitude in excess of 90,000 ft and then burst. A parachute will deploy to control the rate at which the payload descends and will ensure a controlled safe and soft landing.

High ALtitude Balloon Payload Components
Payload Components

The payload will be built around a light-weight platform which will carry a Video Camera, a Flight Computer/APRS Transmitter, and a Commercial Satellite Tracker. The camera will capture a video of the flight and the flight computer will record altitude, temperature and position data and relay this information to the ground via APRS on 2m. A commercial satellite tracker would be included to ensure we could locate the payload once it is back on the ground.

High Altitude Balloon Flight Planning
High Altitude Flight Planning

A key part of the project will involve planning the target altitude and flight path for our balloon. There are some good resources available to help us do this. Check out the Balloon Performance Calculator here. Tools also exist to estimate a balloon’s flight path and track based on Jetstream and other flight parameters.

High Altitude Balloon Tracking
High Altitude Balloon Tracking

Once we launch our balloon, we can track it in flight via the Amateur Radio APRS network on 2m. The payload will transmit position and other information via APRS that will be received by the many APRS receiver stations that have been built by Amateur Radio Operators. The data from our balloon will be relayed to aprs.fi in real-time and will be able to be displayed on any device with internet access and a web browser.

High Altitude Balloon Flight Data Analysis
High Altitude Balloon Flight Data Analysis

Once we recover our balloon payload, we will guide our young team members in analyzing the data from the flight to help them to learn about atmospheric conditions and to prepare to share the results along with the video captured with classmates and other interested groups. You can get an idea of the video that we can expect below.

 

We are working to raise the necessary funds to support our project.  We are counting on the generosity of our members and friends to help us.  Please consider making a donation here.

Fred, AB1OC

Radio Amateurs Developing Skills Worldwide