New 70cm Yagi

M2 Antenna Systems 432-9WLA Specifications

M2 Antenna Systems 432-9WLA Specifications

We decided to replace our current 70cm yagi with a newer, higher performance one from M2 Antenna Systems. We choose the M2 432-9WLA. The new antenna has higher gain and a cleaner pattern than our current 70cm yagi. It also has a longer boom.

New Yagi Ready For Installation

New Yagi Ready For Installation

The first step in the project was to assemble the antenna and check its SWR on the ground. The elements on an antenna like this typically vary by small amounts and are usually not arranged from shortest to longest. It is important to carefully measure each element during installation to confirm that each element is installed at the correct location on the boom.

The folks at M2 Antenna Systems made up a custom boom support truss for us. This is important given the potential for ice and snow accumulation that we face here in New England. We also made up a section of LMR-600uF coax to connect the antenna to the feedline and preamp system on our tower.

Driven Element Details

Driven Element Details

The new antenna uses a Folded Dipole style feed point. This system is essentially a T-matching arrangement where the two sides of the driven element are fed 180 degrees out of phase. It is important to set the locations of the shorting blocks carefully to ensure proper operation of the driven element and a resulting low SWR.

Yagi Going Up The Tower

Yagi Going Up The Tower

Matt, KC1XX, and Andrew from XXTowers handled the installation of the new Yagi on our tower. The installation involved climbing our 100 ft tower and the 25 ft mast at the top to remove the old yagi and install the new one. Note the careful rigging of the new antenna and associated feedline. This allows the new antenna to be pulled up the tower without damaging it.

Climbing a mast is not for the faint at heart! An installation like this one is clearly a job for experienced professionals. Andrew makes this task look easy. Our tower camera captured some video (click on the image above to play) of Andrew’s handy work.

Completed Installation

Completed Installation

The new yagi (top antenna in the picture above) is installed on a 5 ft fiberglass mast extension. The extension is used to ensure that the antenna does not “see” a metal mast which would disrupt the antenna’s pattern. The final installed height of our new yagi is a little over 125 ft. Note Andrew’s good work in attaching the feedline to the mast.

432-9WLA Installed SDR - Shack End

432-9WLA Installed SDR – Shack End

With the new yagi installed and hooked up, we made a final check of the end-to-end SWR from the shack. The antenna’s SWR is very good and the 2:1 SWR bandwidth extends from the bottom of the 70cm band to almost 450 Mhz. The new antenna is optimized for weak signal work up through the ATV sub-band and its SWR is below 1.2:1 in this range.

Fred, AB1OC

Satellite Station 4.0 Part 10 – Adding 23 cm To Our Satellite SDR

Satellite SDR

DEM L24TX Tx Converter

We’ve recently received our L24TX Transmit Converter from Down East Microwave. The unit is compact, simple, and produces up to 25W output in the satellite section of the 23 cm band (1260 MHz – 1270 MHz, actually 24 cm). The L24TX is a transmit-only device that is intended to enable L-band uplinks for Satellite use. This article is about our most recent project which involved integrating the L24TX into our Flex SDR Satellite System.

Satellite SDR

24 cm Tx Converter Rear Panel

Connecting the unit is straightforward. The unit requires an IF input, a 10 MHz reference oscillator, DC power, and a transmit keyline. The later two inputs are provided via a 7-pin connector and a DEM supplied cable. We ordered our unit with the following configuration options:

  • IF 28 Mhz = 1260 MHz output
  • Max IF Drive Level – +10 dBm
  • Fan and Case configured for mounting in the shack

Fortunately, our feedlines for the 23/24 cm band are hardline-based and relatively short. The unit is also available in a configuration that would enable it to be remotely mounted in an enclosure on a tower.

Satellite SDR

24 cm Tx Converter Installation in our Remote Gateway SDR Rack

The unit fits nicely into our Remote Gateway SDR Rack. The L24TX does not include a power output display so we used a 23/24 cm sensor and our WaveNode WN-2 Wattmeter to monitor output power from the unit. The unit does have leads which output a voltage that is proportional to output power. This could be used to build a power output bar display or meter. the front panel indicates display a power-on indication, lock to the 10 MHz clock input, and Tx when the unit is transmitting.

Satellite SDR

Overall Satellite SDR System Design

Integration into our Satellite SDR System was straightforward. Our system already included splitters for the 10 MHz GPSDO and the 28 MHz Transverter outputs from our Flex 6700 SDR. I had hoped to use one of the leads from the SmartSDR BITS cable we are using to key our 70 cm Transverter but the BITS cable did not have an adequate drive level to key the L24TX.

Satellite SDR

Remote SDR Gateway Tx Band Settings

Fortunately, the Flex 6700 has configurable TX1-TX3 outputs for keying devices like Transverters. The use of the TX2 output to key the L24TX was easily configured in the SmartSDR’s TX Band Settings.

Satellite SDR

23 cm Tx Converter Setup in SmartSDR

It is necessary to configure SmartSDR for the L24TX. The required settings are in the XVTR options tab. In addition to configuring the mapping between the Flex 6700’s XVTR IF frequency and the unit’s output Frequency, one needs to set the IF drive levels. We used the default drive level of 6.0 dBm and adjusted the IF Gain Control on the L24TX until the full output of 25W was reached while transmitting a tone. The correct adjustment is apparent when further gain increases do not provide a proportional increase in output power. Proper setting of the RF drive and gain will keep the L24TX’s output in its linear range of operation.

Satellite SDR

Final Power Distribution Design

The L24TX is powered via the power distribution system in our Satellite SDR Rack. Control and current limiting for the 2m LPDA, 70 cm Transverter, and the L24TX are individually controlled via a RigRunner 4005i IP Power Controller.

Satellite SDR

SDR Satellite System Remote Power Control via a RigRunner 4005i

The RigRunner is remotely accessible over the Internet and our network via a password-protected web interface. This enables us to easily power down or power cycle individual components in the Satellite SDR System remotely.

MacDoppler Tracking AO-91

MacDoppler Tracking AO-91

With all of the hardware installation and calibration steps complete, we are turning our attention to the software side of the setup. We will be using MacDoppler for satellite tracking and VFO control of our Satellite SDR System. This creates a need to connect the MacDoppler program which runs on a Mac to SmartSDR and the Flex 6700 which is a Windows-based system. Fortunately, MacDoppler provides a UDP broadcast mode which transmits az/el antenna position information as well as data to control radio VFOs to adjust for Doppler shift.

Satellite SDR

FlexBridge Software Beta

We are working on a custom windows application called FlexBridge to enable MacDoppler to run our Flex SDR-based Satellite System. FlexBridge runs on a Windows PC. It receives and parses the UDP broadcast messages from MacDoppler and uses the FlexLib API to properly configure and control the Flex SDR’s VFOs.

Satellite SDR

SmartSDR Operating With AO-92 in L-V Mode

At present, FlexBridge can configure and control SmartSDR (or a Maestro Client) that is operating our SDR Satellite System. The screenshot above shows the MacDoppler, FlexBridge, SmartSDR combination operating with AO-92 in L/V mode. This software is still an in-progress development and we plan to add the ability for FlexBridge to connect to the radio via SmartLink as well as support for the Green Heron RT-21 Az/El Rotator Controller that we are using. We’ll be sharing more about FlexBridge here as the software development progresses.

The next step in our Satellite Station 4.0 Remote Gateway project will be to move our satellite antenna controls and feedlines into the shack and begin testing the complete setup using local control. Once this step is complete, we’ll focus on the final steps to enable remote operation of our satellite station via the Internet.

Here are links to some additional posts about our Satellite Station 4.0 Projects:

Fred, AB1OC

AMSAT 50th Aniversary Celebration – W3ZM/1 Activations in CT and RI

Source: AMSAT 50th Aniversary Celebration – W3ZM/1 Activations in CT and RI

We continued to test our Portable Satellite Station 4.0 as part of AMSAT’s 50th Anniversary Celebration WAS Activations. You can read about the activations and our station’s performance via the link above. Overall, we were pleased with how the portable setup performed. The weakest link was the downlink performance of our antenna system. We are working on some ideas to improve this element of our setup – more to come on this project…

Fred, AB1OC

 Nashua Area Radio Society Ham Bootcamp @ HamXpostion 2019

The Nashua Area Radio Society (NARS), will be hosting a Ham Bootcamp on Saturday, September 7th from 9 AM until noon at the Northeastern HamXposition at Boxboro. Ham Bootcamp includes a series of hands-on activities designed to help newly licensed Technician and General class license holders get on the air and use their amateur radio license. It is also a great opportunity for prospective hams who are interested in seeing what the hobby has to offer….

Source: Ham Bootcamp @ HamXpostion 2019 – Nashua Area Radio Society

Ham Bootcamp activities will be provided in two tracks – one for Technicians and prospective hams and one for General class licenses and higher.

Technician Track Activities

  • Putting together a Station for Repeaters – how to pick an HT and antenna
  • HT Programming Tutorials and Help
  • Getting Started with EchoLink
  • Making a Contact, joining a Repeater Net
  • Fox Hunting Demonstrations
  • Making contacts through Amateur Radio Satellites in Space

General Track Activities

  • Putting together an HF Station
  • Putting up a simple HF Antenna including coax and grounding choices
  • Software for your HF station
  • Operating on the HF bands using voice, morse code, and digital
  • Putting together a portable HF Station
  • How to find and work DX and QSL

… and more!

We will also be providing discount coupons for a kit build and for purchases at HRO to Ham Bootcamp participates.

Ham Bootcamp is free and it is available to all HamXpositon 2019 attendees. Participation in the hands-on training is limited to 100 people maximum and will be on a first-come, first-served basis, so arrive early to get a seat. Registration begins at 8 am.

If you are planning to attend the Northeastern HamXpostion 2019 @ Boxboro on September 7th, don’t miss this once a year opportunity to learn more about Amateur Radio, improve your station, expand your skills, and get on the air. See you at Ham Bootcamp!

Fred, AB1OC

Get A Custom Program for Your HT at HamXpostion 2019

It seems that Hams struggle a bit to get their HTs programmed with the right set of repeaters and other memory settings. The Nashua Area Radio Society will be offering a custom HT Programming Clinic at HamXposition @ Boxboro 2019 to help hams get their HT’s programmed…

Source: Get A Custom Program for Your HT – Nashua Area Radio Society

I’d like to invite our readers who are planning to attend the Northeastern HamXposition 2019 @ Boxboro on September 7th and 8th to bring their HT. We will be providing an HT Programming Clinic at the show and we’d be happy to create a custom program for your HT and location. Our custom programs can also include FM Satellites, Foxes, and more!

Fred, AB1OC

Satellite Station 4.0 Part 9 – Upgraded Simple Portable Station

Portable Satellite Station

Portable Satellite and Grid Square Activation Station

We were up on Mt. Washington here in New Hampshire this past weekend and we decided to use the SOTA activation as a test for our updated Portable Satellite Station 4.0. It turned out that the station was also a great SOTA and Grid Square Activation station for terrestrial contacts.

An upgraded Portable Satellite Station has been part of our 4.0 Satellite Evolution plan from the start. The goals for the station included:

  • Support for FM and Linear Satellite Contacts
  • Computer Control to handle Doppler Shift
  • A simple, easy to deploy portable antenna system for 2m and 70cm
  • Full-Featured 100w/75w Transceiver with External Preamps for good weak-signal performance
  • Quite, Green Power using Solar Energy and Batteries

Station Components

Our upgraded portable station uses the following components:

Portable Antenna System

Elk Antenna on Tripod

We decided to keep our antenna system simple and quick to deploy. We choose a portable 2m/70cm antenna from Elk and mounted it on a camera tripod. A carpenter’s slope gauge is used as an elevation indicator and our iPhone serves as a compass to point the antenna in the azimuth direction. A weighted bag, Bungie cord, and a tent stake anchor the tripod in the windy conditions on the mountain. A 15 ft length of LMR-240uF coax with N-connectors make the connection between the antenna and the rest of the station.

Station Transceiver and Supporting Gear

Portable Station Transceiver and Preamps

We decided to mount the station Transceiver and supporting gear on a piece of plywood to make it easy to transport and setup. The components from lower-right moving counter-clockwise include:

The preamps are powered and sequenced by the IC-910H through its coax outputs. The 70cm side of the second diplexer is used as a filter to prevent transmissions on 2m uplinks from de-sensitizing 70cm downlink signals.

Portable Station Electronics

The use of the mounting board for all of the components allows the station to deployed quickly and helps to ensure reliable operation.

We used a MacBook Air Laptop running MacDoppler to control the transceiver’s VFOs (via a USB CI-V cable). MacDoppler also provided azimuth and elevation data used to point the antenna during satellite passes.

Portable Power

Portable Solar-Battery Power System

Powering a 100w radio in a way that allows continuous use for a day can be a challenge. It’s important to do this in a way that that does not generate noise so we do not disturb others trying to enjoy the outdoors. We met all of these needs using a combination of solar power and batteries.

Portable Solar Power

The primary source of power comes from a pair of 90w foldable solar panels from PowerFilm. The panels are wired in series and connected to an MPPT Charger which charges a pair of batteries. This approach allows the system to provide usable power when it is cloudy and the voltage output of the solar panels drops.

We use a pair of A123 10 Ah LiPo battery packs to supply high-current capacity when transmitting. The solar-battery combination is capable of maintaining full battery voltage while supporting the continuous operation of our station for a full day.

The MacBook Air Laptop batteries are adequate to operate the station during the available satellite passes. We have a 12V DC to 120 VAC inverter which can power the computer from our solar battery setup if needed.

Station Performance

View from Mt. Washington Summit

Our portable station did very well during its initial test! I had to move the antennas and operate the station by myself on this activation which limited my ability to make a large number of contacts during the limited number of satellite passes that were available. Still, I was able to make 6 solid contacts through AO-91 and AO-85 while on Mt. Washington. I did not have a suitable linear satellite pass to make contacts but I was able to hear the EO-88 beacon with no problems and confirm that the doppler correction system was working well.

The station also put in a great performance visa-vie 2m terrestrial contacts. We made a total of 70 contacts using 2m FM and USB! We received many good signal reports with our longest contacts being some 275 mi from our location. We also worked stations on four other SOTAs this way.

Learnings and Next Steps

Our station exceeded my expectations during our initial test on Mt. Washington – especially in terms of the number of Terrestial Contacts that I was able to make with it. I did notice that the transmit side of the system was quite a bit stronger than the receive side. This is an indication that a better antenna would help.

We changed the antenna polarization to vertical for 2m FM contacts and to horizontal for 2m USB contacts. This helped the receive side performance quite a bit.

I found that a headset was essential for satellite and terrestrial weak-signal operation in USB mode. I was able to use the hand microphone and the radio’s speaker for most of the 2m FM contacts that I made. This gave interested onlookers a chance to experience Amateur Radio.

Satellite operation would have been much easier and more productive with a helper to handle pointing the antenna while we operated. This improvement will need to be coupled with a headset/speaker combination that allows the person pointing the antenna to hear the quality of the downlink while moving the antenna and finding the best polarization.

I am looking forward to doing some grid-square activations using our upgraded portable station. It was a pleasant surprise to find as much interest in Terrestial contacts on the 2m band as we did. The Nashua Area Radio Society does several SOTA activations each year and I am looking forward to using that station for these as well.

Here are links to some additional posts about our Satellite Station 4.0 Projects:

Fred, AB1OC

Learn About Ham Radio at HamXposition @ Boxboro

Remote HF GOTA Station at HamXpositon

The Nashua Area Radio Society will be hosting several activities and displays at HamXposition this year. Our planned activities include:

  • NEW! Ham Bootcamp Program – a hands-on activity to help folks get on the air and build their stations
  • Our Ham Expo Display featuring information and hands-on activities you can do with Amateur Radio
  • Kit Building Activity featuring a choice of two different kits
  • Multiple Get On The Air Stations including an HF Remote GOTA station and an on-site Satellite GOTA station
  • Special Event Station using the N1T Callsign
  • NEW! Radio Programming Station – Get your FM HT programmed with a custom repeater list for your location
  • Two Forum Presentations by Nashua Area Radio Society Members

The ARRL and the HamXposition team have been helping us to promote our activities. You can see what the ARRL is saying about our plans in their recent posting – Dayton Hamvention Radio Club of the Year to Hold Ham Bootcamp at New England Convention.

You can learn more about HamXposition and our activities there at the HamXpostion website.

Ham Bootcamp

A First HF Contact at Ham Bootcamp

We have created a program that we call Ham Bootcamp. Bootcamp to helps recently licensed and upgraded hams to get on the air. We are making this program available to up to 100 HamXpostion attendees on a first-come-first-served basis.

Our Bootcamp program will run from 9 am to noon on Saturday, September 7th in the Federal Room. Bootcamp will feature tracks for both Technician and General class license holders. It is also a great place for folks who are not yet licensed to learn more about Amateur Radio and how to get on the air.

Our Bootcamp program will include:

  • How to make a contact and join a repeater net
  • Putting together an HF station
  • Radio, antenna, and feed line choices
  • Getting started with FT8 and digital modes
  • Exchanging QSL cards
  • Learning Morse code
  • Tips on upgrading
  • Introduction to ham radio kit building
  • Handheld radio programming tutorials

Ham Bootcamp is free.  Participants will receive discount certificates for a kit build at the show and for purchase of Ham Radio Gear from Ham Radio Outlet.

You can learn more about Ham Bootcamp on the HamXposition website and on our website.

Source: Interest and Excitement Around HamXposition Is Building

I wanted to share our plans for several hands-on activities at HamXposition @ Boxboro in September. We hope that Ham Bootcamp will be of particular interest to folks getting into Amateur Radio. You can learn more about Ham Bootcamp and all of our planned activities via the link above. We hope to see some of our readers at HamXpostion next month!

Fred, AB1OC

A Raspberry Pi Video Player for Ham Expo Displays

Dave, K1DLM recently prototyped a simple Raspberry Pi Video Player for use in our Ham Exposition Displays. We’ve built a number of these players to play video content at our upcoming Ham Expo Display at HamXposition at Boxboro in September. The article below shares information on the hardware and software we used to put these players together. The information should provide a useful start for many other Raspberry Pi projects.

Source: A Raspberry Pi Video Player for Expo Displays – Nashua Area Radio Society

Simple Raspberry Pi Computers have many useful applications in Amateur Radio. They can also be used to create a nice general purpose computing platform for many applications.

The hardest part of using the Raspberry Pi is getting the basic hardware and software components together to create a working system. This article explains these basic steps for a simple video player application that we use as part of our Ham Radio Expo Displays. I hope that this information is useful to others who might want to use the Raspberry Pi.

Fred, AB1OC

Video About Growing and Modernizing Your Amateur Radio Club

Jamey, AC1DC Presenting in the ARRL Forum at Dayton 2019

The ARRL gave the Nashua Area Radio Society a Forum at the Dayton Hamvention(R)this past year to talk about how we approached Growing and Modernizing our club. The ARRL has produced a video of our Dayton Forum presentation. You can view the Video along with a copy of the presentation via the link which follows…

Dayton Hamvention(R) 2019 ARRL Forum – Growing and Modernizing Your Amateur Radio Club

The Nashua Area Radio Society has grown from about 35 members to over 225 members in less than 4 years. The presentation contains ideas and programs that have worked for the Nashua Area Radio Society’s (NARS) as part of our efforts to modernize and grow our club.

We have been sharing this presentation via the Internet with other Amateur Radio Clubs. All that is required is an Internet connection capable of streaming video and an associated computer with a projector and speakers. We would like to invite our readers who might want us to do a similar presentation at one of your club meetings to reach out to us via an email to ab1oc@arrl.net.

Fred, AB1OC

GPS Time Server

GPS NTP

GPS Controlled Time Server

There are many reasons to have an accurate time source in your station. Getting the best performance from WSJT-X modes like FT8 requires your computer clock to be synchronized to within a second for example. You can set your clocks accurately using NTP servers on the Internet. This is the most common way that most stations set their clocks.

What if you are portable and don’t have Internet access or what do you do if your Internet connection goes down? One way to solve these problems is to use a GPS controlled NTP time server in your station. We recently installed one from Leo Bodnar in our station.

GPS NTP

GPS Antenna

This device is simple to install. It just requires an Ethernet connection to your network and a GPS antenna. The antenna is included with the unit. The antenna will need to be outdoors with a reasonably clear view of the sky.

GPS NTP

GPS Satellite Lock Screen

After a minute or so after it is installed and powered up, the unit will synchronize to the visible GPS satellites in your location and report its coordinates. This indicates that you have a good GPS system lock and that the clock in the unit is accurate to within a microsecond.

GPS NTP

NTP Summary Screen

The unit gets its IP either from DHCP or via a fixed IP address that you can program. Once the unit is set, you use its IP address as the NTP server in your software to set your clocks. You would set you NTP server in a program like Dimension 4 to accurately set your computer’s clock for example. You will want to disable your computer’s normal Internet clock setting function to avoid conflicts with Dimension 4. Once this is set up, your computer clock will be synchronized to the GPS system and will be very accurate and you will get the best performance from WSJT-X.

Fred, AB1OC