Greencube (IO-117) – A Portable Station for Activating Grid Squares

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Portable Station for Greencube

Portable Station for Greencube

We’ve been having a lot of fun with the Greencube (IO-117) satellite, so I decided to put together a portable ground station for activating grid squares. I wanted a station that –

  • Has adequate antenna gain and power for reliable Greencube operation
  • Uses solar-battery power so that it is quiet when operating in public places
  • Uses computer management for Doppler correction
  • Can provide accurate grid locator information via  a GPS receiver
  • Is easy to set up in the field in less than 30 minutes

Station Components

We already have a solar-battery power system that we build for portable operation with a 100w transceiver as well as an IC-9700 transceiver that we use as part of our transportable satellite ground station. We also have Windows and Mac laptop computers that we can use as part of our Greencube (IO-117) portable ground station. With these components in mind, here are the hardware components that we are using as part of our Greencube portable station –

We are using the following software for our portable Greencube (IO-117) ground station:

Portable Station in Pelican Case

Portable Station in Pelican Case

We also purchased a case (Pelican Air 1555) to package the transceiver and accessories.

Antenna System

M2 Antenna Systems 440-11X Antenna

M2 Antenna Systems 440-11X Antenna

We choose the M2 Antenna Systems  440-11X Antenna for our portable ground station. This antenna has more than adequate gain for use with Greencube, and its lightweight rear-mounted design makes it ideal for use with our heavy-duty video camera tripod.

Portable Antenna System

Portable Antenna System

The antenna is attached to the tripod using a Camera Tripod Ball Mount, a Handlebar Ball Mount Clamp, and a Double Socket Ball Arm. The Handlebar Clamp grips that antenna’s rear extension and allows the antenna to be easily rotated to align its polarity with Greencube’s antenna during a pass. A short section of water pipe with a cap, hook, and a 1,000-gram weight provides a counterweight to balance the antenna on the tripod.

Portable Antenna System Details

Portable Antenna System Details

A Magnetic Digital Angle Guage is used to adjust the elevation angle of the antenna.

A coax-powered LNA from Advanced Receiver Research (an available alternative is the SSB Electronic SP 70 preamp) is attached to one of the legs of the tripod and is connected to the antenna with a short LMR-240uF coax cable. a 20′ length of LMR-400uF coax connects the antenna system to the transceiver. N-connectors are used throughout the feedline system.

Radio, Computers, and Software

IC-9700 Transciver and Computers

IC-9700 Transceiver and Computers

Our setup uses an Icom IC-9700 transceiver and two computers. The IC-9700 transceiver is connected to the Windows computer via the radio’s USB port and to the MacBook Air via a CI-V cable.

The Windows computer runs the following software programs to provide the client terminal, modem, and logging functions required to operate with Greencube –

The configuration of these programs is covered in more detail here.

GPS Dongle NMEATime Software

NMEATime Software used with GPS Dongle

The Windows laptop also runs the NMEATime application and uses a USB GPS Dongle to accurately determine the grid locator where we are operating from. The grid locator from NMEATime is used to configure MacDoppler to ensure accurate tracking information for aiming our antenna.

MacDoppler Tracking Greencube and Controlling the M2 LEO Pack

MacDoppler Tracking Greencube and Controlling the Uplink/Downlink Frequencies

The MacBook Air laptop runs MacDoopler. MacDoppler is connected to the IC-9700 transceiver via a CI-V cable and controls the IC-9700’s uplink and downlink frequencies to provide Doppler correction. MacDoppler is also used to determine the azimuth and elevation of Greencube to enable manual pointing of our antenna.

Power System

Solar-Battery Power System

Solar-Battery Power System

Powering a 100-watt transceiver in a portable application during extended operating sessions can present a challenge. I also wanted a setup that was quiet as we often operate portable in public locations. For these reasons, I decided to put together a solar-battery setup that consists of the following components:

90W Foldable Solar Panels

90W Foldable Solar Panels

The solar panels are wired in series and provide about 34 Vdc in bright sunlight.

MPPT Charge Controller, NLiPo Batteries, and Power Distribution

MPPT Charge Controller, LiPo Batteries, and Power Distribution

The MPPT Charge Controller automatically determines the best balance between cell voltage and current to provide maximum power transfer to charge the batteries. The batteries provide the extra power capacity needed when transmitting. The resulting power setup can sustain the full power operation of our portable station, even on cloud days.

The laptops run on their internal batteries and are changed via automotive lighter socket power adapters between operating sessions.

Operating Using Greencube

Portable Telemetry from Greencube

Portable Telemetry from Greencube

My initial tests of the portable station were done using the station to receive Telemetry from Greencube. This allowed me to learn to steer the antenna and adjust it for the best polarity during passes. The station had no trouble hearing and decoding Greencube’s telemetry transmission from horizon to horizon.

Compass App on iPhone

Compass App on iPhone

It was relatively easy to point the antenna based on the azimuth and elevation information from MacDoppler. I used a compass app on my iPhone to set the antenna’s azimuth heading and the Digital Angle Guage to set the antenna’s elevation. Pointing the antenna to within +/- 10 degrees of accuracy was adequate for reliable operation with Greencube.

I turned the speaker volume on the radio high enough so I could hear Greencube’s signal while adjusting the antenna polarity. Finding the polarity that caused Greencube’s signal to be weakest and then rotating the antenna 90 degrees from this point worked well.

Portable QSOs with EA8ARI via Greencube

Portable QSOs with EA8ARI via Greencube

I was able to make 15-20 contacts on each Greencube pass with our portable ground station. The RSSI graph in the Greencube terminal is a good indicator to determine when to adjust the antenna’s heading and polarity to track Greencube during a pass. It’s best to have a helper with one person making contacts and the other adjusting the antenna, but it’s possible for a single operator to do both jobs and still make many contacts during a pass.

More Fun With Greencube

I am quite pleased with the performance of our new portable ground station for Greencube (IO-117). Anita and I are planning a portable grid square activation trip for later in the fall to make use of the station.

This article is the fifth in a series that we are working on. You view the other articles via the links below. This is a work in progress, and we’ll be creating additional Greencube-related posts in the near future:

You can also read more about our Satellite Ground stations here.

Fred, AB1OC

EME Station 2.0 Part 14 – New 1.5 Kw Amplifier

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W6PQL 2 Meter 1.5 Kw Linear Amplier

W6PQL 2 Meter 1.5 Kw Linear Amplifier

I’ve recently upgraded the Amplifier for our 2m EME station to one that can provide full-duty cycle operation at 1500 watts. The digital modes used for EME on 2m (JT65 and Q65) require an amplifier that can sustain full output for periods of 1 minute or more as well as sustain full power operation at a 50% duty cycle over an extended period of time.

I’ve had great experiences with Jim Klitzing, W6PQL’s amplifiers in our station so I contacted Jim to build a new 2m amplifier for our EME station.

Construction and Setup

W6PQL 2m 1.5 Kw Linear Amplifier Interior View

W6PQL 2m 1.5 Kw Linear Amplifier Interior View

Jim does an excellent job with the design and construction of his amplifiers. The parts are top-notch and the quality of construction and attention to detail are second to none. Jim provides components and sub-assemblies as well as some turn-key amplifiers.

He hand-builds each amplifier to his customer’s specifications and there is usually some wait time to receive a completed amplifier. The results are absolutely worth the wait!

W6PQL 2m 1.5 Kw Linear Amplifier Rear Panel

W6PQL 2m 1.5 Kw Linear Amplifier Rear Panel

The connection and setup of the amplifier was straightforward. It is well worth the effort to hook up an ALC feedback connection from the amplifier to your exciter. In our case, we are using an Icom IC-9700 to drive the amplifier. This radio does not have a positive sequencing control input for the power stage of the transceiver. Our setup uses an external sequencer to manage transmit and receive changeover and protect our tower-mounted preamplifiers. We have had numerous problems where sequencing errors damaged our preamps.

One of the unique features of Jim’s Amplifier Control Board is the inclusion of an ALC hold-back capability. The amplifier can be configured to send an output limiting ALC voltage to the driving transceiver to prevent any power from being applied until the sequencer completes the final Tx changeover step by keying the amplifier. This feature requires additional amplifier adjustment (the adjustment procedure is well covered in the documentation). This capability has eliminated the issue of sequencing problems causing damage to our preamplifiers!

Power Supply

Meanwell Power Supply

Meanwell RSP-3000-48 Power Supply

The recommended power supply for this amplifier is a 48-volt, 62.5-amp switching design from Meanwell (Model RSP-3000-48). Jim set up the supply and provided the cabling to connect it to the amplifier. The supply is 240 VAC powered and is quite efficient. Jim adjusted the power supply’s output voltage and tested the amplifier with it with the amplifier before shipping.

Controls and Operation

W6PQL 2 Meter 1.5 Kw Linear Amplier Controls and Meters

W6PQL 2 Meter 1.5 Kw Linear Amplifier Controls and Meters

The operation of the amplifier is straightforward. It is best to set the driving transceiver for a watt or so and perform some initial test transmissions to ensure that the antenna system is presenting a low SWR and that your station’s sequencing system is operating correctly. Note the LNA and Amplify Controls must be turned on for the ALC holdback feature to work correctly.

The amplifier provides PA Voltage and PA Current meters as well as bar-graph displays for Forward and Reflected power.

More Articles on EME

We are very pleased with our new amplifier! I’ve used it for quite a few contacts, and it performs great. It provides a full 1500 watts output with the digital modes used for EME work.

You can read more about our EME station project via the links that follow:

If you’d like to learn more about How To Get Started in EME, check out the Nashua Area Radio Society Tech Night on this topic. You can find the EME Tech Night here.

Fred, AB1OC

Greencube (IO-117) – M2 Antenna Systems LEO Pack – Will It Work?

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LEO Pack Transportable Satellite Antenna System

LEO Pack Transportable Satellite Antenna System

Quite a few folks have the M2 Antenna System LEO pack antenna. I wanted to see how this antenna system would perform with Greencube (IO-117). Our LEO Pack is set up on a Glen Martin roof tower that we’ve modified to create a transportable ground station. Here are some of the specs for the setup we’ve tested:

The specifications for the 70cm antenna are as follows:

  • Frequency Range: 432 To 438 MHz
  • Gain: 13.3 dBic
  • Front to back: 15 dB Typical
  • Beamwidth: 42° Circular

The published gain number for this antenna meets the requirements for operation with Greencube, so we set up our transportable station in our backyard and proceeded to do some testing.

Transportable Ground Station

LEO Pack Transportable Ground Station Radio and Computers

Transportable Ground Station Radio and Computers

The ground station setup includes an IC-9700 Transceiver, a Green Heron RT-21 AZ/EL Rotator Controller, and two computers.

MacDoppler Tracking Greencube and Controlling the M2 LEO Pack

MacDoppler Tracking Greencube and Controlling the M2 LEO Pack

The Mac laptop runs MacDoppler, which handles steering the antennas and Doppler correction, and the Windows laptop runs the modem and client software to access Greencube’s Digipeater.

The antennas are located about 100 ft from the rest of the ground station and are connected using LMR-600uF coax cable. This results in about 40 watts of power being delivered to the feedpoint of the 70 cm antenna.

Testing The LEO Pack With Greencube’s Digipeater

Greencube (IO-117) QSOs with the LEO Pack Antenna System

Greencube (IO-117) QSOs with the LEO Pack Antenna System

I am happy to report that the LEO Pack 70cm antenna enabled us to make quite a few contacts using the Greencube Digipeater. The setup required the remote preamp to be on and the use of the polarity switching controls to optimize losses due to mismatched polarity, which occurred frequently during Greencube passes. The LEO Pack antenna/preamp combination provided consistent decodes of Greencube’s packets. The challenge was getting our packets to be Digipeated by Greencube. On some passes, this worked very well. During other passes, we were only able to get reliable Digipeats during the approaching portion of a pass at elevations above 25 degrees.

Optimizing Our Station

MacDoppler Optimized Frequency Settings for Greencube

MacDoppler Optimized Frequency Settings for Greencube

I spent a lot of time determining the best uplink frequency to use with Greencube’s Digipeater. The settings above are what I finally settled on for uplink and downlink frequencies.

Optimized Soundmodem Settings

Optimized Soundmodem Settings for Greencube (IO-117)

I also spent some time experimenting with the Soundmodem settings. The lengthened Tx lead-in and tail settings above helped Greencube decode our signals more reliably.

These adjustments also improved the Digipeating performance of the larger antennas used in our main ground station, so they are not specific to the LEO Pack.

Conclusions About The LEO Pack and Greencube

I probably made about 50 contacts using Greencube and our LEO Pack antennas. If you already have a ground station built around the LEO Pack Antenna System, I would encourage you to add a preamplifier if you don’t already have one and try Greencube.

If you are building a fixed ground station for use with Greencube, it might be better to step up to a larger antenna such as the M2 Antenna Systems 436CP30.

I have also found that antennas with circular polarity are not necessarily the best for Greencube. This is likely due to a combination of the lengthened path through the ionosphere due to Greencube’s altitude, resulting in stronger polarity rotational effects and mismatches with the circularly polarized antennas we are using. I am anxious to do some more testing with the non-circularly polarized yagi that we are using with our portable station to see if I can confirm this.

More Fun With Greencube

This article is the fourth in a series that we are working on. You view the other articles via the links below. This is a work in progress, and we’ll be creating additional Greencube-related posts in the near future:

You can also read more about our Satellite Ground stations here.

Fred, AB1OC

Greencube (IO-117) – Completing a Satellite Worked All States

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AB1OC Satellite Worked All States

AB1OC Satellite Worked All States (WAS)

I have worked and confirmed all states in the USA for some time now except for Hawaii. It is simply impossible to work Hawaii from my location in New England via a Low Earth Orbit (LEO) satellite. Fortunately, the Greencube (IO-117) Medium Earth Orbit (MEO) satellite has made a contact with Hawaii possible. The next challenge was finding an active Amateur Radio satellite operator set up for Greencube.

Developing a Plan

KH6WI is QRV in Hawaii!

KH6WI is QRV in Hawaii!

After doing some online research, I was pleasantly surprised to find Eric Olson, KH6WI, was preparing a portable setup for Greencube! This motivated us to set up the software to use Greencube from our station here.

Making the Contact

Eric KH6WI Calling CQ from Hawaii

Eric KH6WI Calling CQ from Hawaii

With everything set up and working for operation with Greencube, I anxiously awaited Eric’s first activation. I was thrilled to see him calling CQ during one of the first passes that he was active on.

The Contact with KH6WI

The Contact with KH6WI

The contact with Eric was easily made and quickly confirmed via LoTW. With this done, I had finally completed my Satellite Worked All States!

Grids, Grids, Grids

AB1OC Satellite Grids

AB1OC Satellite Grids

I’ve been active on Greencube for about a month and have made over 320 contacts via Greencube, bringing my total satellite contact count to over 3,200. Greencube has helped me confirm several new DXCCs via Satellite and increased my worldwide grids to over 415 grids.

If you have not tried Greencube (IO-117), I’d encourage you to set up your station to work this bird. It’s not difficult to do this, and Greencube opens the world to Amateur Satellite operators.

More Fun With Greencube

This article is the third in a series that we are working on. You view the other articles via the links below. This is a work in progress, and we’ll be creating additional Greencube-related posts in the near future:

You can also read more about our Satellite Ground stations here.

Fred, AB1OC

Greencube (IO-117) – Setup, Software, and Operation

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Typical Greencube Pass Providing DX Possibilities

Typical Greencube Pass Providing DX Possibilities

Greencube (IO-117) is a Medium Earth Orbit (MEO) satellite that carries a 70cm digipeater. This satellite can provide DX contacts covering a wide area around an Amateur Radio satellite ground station. Putting together a station and the necessary software to use Greencube is not difficult. If you already have a computer-controlled satellite ground station that works on 70cm, you may already have most of what is needed. We’ll cover Greencube (IO-117) setup in detail in this article.

Operating with Greencube – What’s Required

Greencube (IO-117) requires the following for successful contacts via its digipeater:

  • A directional antenna with at least 12 dBi gain
  • A 70cm SSB/FM capable Transceiver with a soundcard interface and at least 25 watts of output at the antenna
  • Software to control the Transceiver to correct for Doppler shift and provide antenna tracking control or pointing information
  • A computer running modem software and a Greencube Terminal Program
  • A low-noise preamp at the antenna is recommended

Greencube Satellite Antennas

Satellite Antennas Tracking Greencube (IO-117)

Tower Mounted Satellite Antennas Tracking Greencube

We have three different antenna combinations that are Greencube capable here:

ARR Satellite Preamp

ARR Satellite Preamp

All three antennas have Advanced Receiver Research Low-Noise preamps which are powered via the associated antenna’s coax feedline. Unfortunately, the ARR preamps are no longer available. A good alternative would be the SSB Electronic SP 70 preamp. I recommend choosing a preamp that can be sequenced using coax power from your transceiver if your transceiver supports coax-powered preamps. This approach ensures that your preamps are protected from transmit power in most operational scenarios.

Radio, Computers, and Power

New IC-9700

Icom IC-9700 Transceiver

All of our Greencube (IO-117) setups use an Icom IC-9700 Transceiver.

We use two computers to run our stations:

  • A Mac (iMac or MacbookAir) running MacDoppler to control antenna tracking and to control our IC-9700 to perform Doppler correction
  • A Windows PC running the modem, terminal client software, and a logger for using Greencube’s digipeater and for decoding telemetry
Greencube (IO-117) Setup - Transportable Ground Station Radio and Computers

Transportable Ground Station Radio and Computers

Using the two computers means that both must simultaneously control the IC-9700 via the radio’s CAT interface. This is easily accomplished with the IC-9700 by using both the CI-V and USB CAT interfaces. The radio’s CI-V interface is used with MacDoppler, and the USB interface is used with the Windows PC to connect the IC-9700’s Rx and Tx audio to the modem SW and to provide for PTT via a COM port.

We use AC power for our fixed and transportable setups.

Portable Solar-Battery Power System

Our portable setup uses solar power consisting of two 90-watt foldable panels, an MPPT charger system, and a pair of A123 LiPo batteries. We’ll share more about our portable and transportable setups in subsequent posts.

Software

Greencube Client and Modem Software

Greencube Terminal and Uz7HO Modem Software

We use the following software for our Greencube (IO-117) ground station:

MacDoppler runs on a Mac computer (iMac or Macbook Air), and the rest of the software runs on a Windows PC.

The links above include instructions for setting up each of the software applications. The following are some notes on Greencube (IO-117) setup for each software component.

MacDoppler

Greencube (IO-117) Setup - MacDoopler Configuration for Greencube

MacDoopler Configuration for Greencube

The Greencube (IO-117) setup in MacDoppler configures the IC-9700 Transceiver to operate in simplex SSB digital mode. This is the SSB-D choice in MacDoppler’s Modes tab for Greencube.

MacDoppler Uplink and Downlink VFO Offsets

MacDoppler Uplink and Downlink VFO Offsets

You’ll want to select SSB-D mode in MacDoppler to track Greencube and configure the IC-9700 to work with the Greencube digipeater. Setting the uplink and downlink offsets to -1.200 KHz will place Greencube’s packet transmissions in the middle of the IC-9700’s passband.

UZ7HO Soundmodem

UZ7HO Sound Modem Greencube Packet Decoding Greencube Packets

UZ7HO Sound Modem Greencube Packet Decoding Greencube Packets

There is a specific version of UZ7HO’s Soundmodem for use with Greencube (see the link above to download greentnc.zip). The soundcard and PTT COM port interfaces provided via the USB connection to the IC-9700 must be configured in Soundmodem.

Soundmodem Devices Settings

Greencube (IO-117) Setup - UZ7HO Soundmodem - Devices Setup

UZ7HO Soundmodem – Devices Setup

The USB connection from the IC-9700 to a Windows PC will create a pair of sound devices (in this example, USB Audio CODEC) and a COM port (in this example, COM15) for CAT and PTT control. These must be properly configured in the Settings – Devices choice on the Soundmodem main menu.

Soundmodem Modem Settings

UZ7HO Soundmodem - Modem Setup

UZ7HO Soundmodem – Modem Setup

The Settings – Modems choice on the Soundmodem main menu brings up this dialog. The settings are the default ones. Note that Soundmodem has two modes – GreenCube 1200bd and GreenCube 300bd. The GreenCube 1200bd setting is normally used for digipeater operation, including decoding telemetry when enabled. You’ll need to use the GreenCube 300bd setting to decode telemetry if Greencube’s digipeater is turned off.

IC-9700 Transceiver Settings

There are some important adjustments to the configuration of the IC-9700 that need to be made for Soundmodem to work properly with the transceiver.

IC-9700 CI-V Settings

IC-9700 CI-V Settings

Configuring the CI-V USB Port to Unlink from [REMOTE] is necessary to allow it to function independently for the other interfaces.

IC-9700 USB AF Output Settings

IC-9700 USB AF Output Settings

You’ll want to set the AF Output Level of the USB interface to about 25% of the maximum and adjust the Windows audio control in Control Panel to get a display on the Soundmodem waterfall of about the intensity shown above.

IC-9700 USB Modulation Input Settings

IC-9700 USB Modulation Input Settings

Setting up the Tx audio levels is important to avoid overdriving the Transmitter. A good place to start is to set the USB Mod Level in the IC-9700 to about 25%.

IC-9700 Tx Drive Setting for One ALC Bar

IC-9700 Tx Drive Adjustment for 1-2 ALC Bars

Then adjust the Windows audio control in Control Panel to get full transmitter output power with only one or two bars of ALC indication on the IC-9700’s ALC meter when transmitting via the Greencube Terminal client. This adjustment is an essential part of your Greencube (IO-117) setup.

OZ9ARR’s Greencube Terminal Setup

Greencube Terminal and Modem Software

Greencube Terminal and Modem Software

A client program is required to format and decode the packets from Greencube. We are using OZ9ARR’s Greencube Terminal for this purpose. This program includes a macro button capability to help you format Greencube Tx packets and includes some nice capabilities for logging contacts and identifying new DXCCs, Grids, and Stations that you have not yet worked.

Greencube (IO-117) Setup - Greencube Terminal Setup

Greencube Terminal Setup

We are using Greencube Terminal with N3FJP’s ACLog to log contacts made with Greencube. This makes it easy to export our contacts to an adif file after each Greencube operating session and import them into our main logger. We also periodically export an adif file containing all of our satellite contacts from our main logger and provide access to this file so Greencube Terminal can determine what we’ve worked before. OZ9ARR’s Greencube Terminal webpage thoroughly explains how to set up and use the program.

DK3WN’s Greencube Telemetry Decoder

DK3WN's Greencube Telemtry Decoder

DK3WN’s Greencube Telemetry Decoder

Greencube periodically sends Telemetry information. You can decode it by using DK3WN’s Greencube Telemetry Decoder with Soundmodem. You can download the decoder and see how to install it on DK3WN’s webpage.

Making Contacts with Greencube

Greencube Terminal and Modem Software

Greencube Terminal and Modem Software

With your Greencube (IO-117) Setup complete, you should be ready to make some contacts! Begin by starting up all of the software and configuring MacDoppler to track Greencube in SSB-D mode. When Greencube is in range, you should see Greencube’s packet transmission being displayed in Soundmodem’s waterfall, and you should be able to hear the packet bursts on your Transceiver. Adjust the Soundmodem decode pointers by dragging them with your mouse to center them in the waterfall traces received in Soundmodem. The setting should be around 1400 – 1500 Hz. Also, make sure that GreenCube 1200db mode is selected in Soundmodem. You should see packets being decoded by Soundmodem.

Greencube (IO-117) Setup - CQ Button

CQ Button

Greencube (IO-117) Setup - INFO Button

INFO Button

Greencube (IO-117) Setup - RRR Button

RRR Button

Greencube (IO-117) Setup - 73 Button

73 Button

You can configure the Shortcut buttons to handle the steps needed to make a contact. The images above show the setup of the buttons that we are using here.

Greencube Terminal Working JH8FIH

Greencube Terminal Working JH8FIH

You’ll want to set the Tx delay for 0 – 2 seconds to give your preamp time to recover from transmitting before you receive your digipeater packets back from Greencube.

You can begin to make a contact by either clicking on another station’s CQ to load the station’s callsign or by just calling CQ yourself. Next, use the INFO button to send your callsign and grid square and then the RRR and 73 buttons to complete your contact. When you are done, you can right-click on the last packet in the exchange or on the station’s callsign that you have worked in one of the right windows to log the contact. That’s all there is to it!

Note that you’ll want to confirm that Greencube has heard and digipeated each of your transmissions. Collisions, fading, and other effects will often cause your packets to not be digipeated, and you’ll need to repeat your transmission until it is digipeated by Greencube.

You can also use the digipeater in store-and-forward mode by setting a long TX Delay (the number is in seconds). This can be as long as several hours to allow you to have Greencube digipeat your packet on the other side of the world! Note that store and forward contacts do not count for operating awards such as Worked All States, VUCC, or DXCC.

The video above shows Uz7HO Soundmodem and OZ9AAR’s Greencube Terminal being used to make contacts during a Greencube pass. the video also demonstrates some of Greencube Terminal’s features for identifying unworked calls and grids. You’ll want to spend some time reading OZ9AAR’s webpage to learn about and take maximum advantage of the many features Greencube Terminal can provide.

More Fun With Greencube

This article is the second in a series that we are working on. You view the other articles via the links below. This is a work in progress, and we’ll be creating additional Greencube-related posts in the near future:

You can also read more about our Satellite Ground stations here.

Fred, AB1OC

Greencube (IO-117) – A New Satellite for DX!

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Greencube (IO-117)

Greencube (IO-117)

The Amateur Radio satellite community is fortunate to have a relatively new Medium Earth Orbit (MEO) satellite. The satellite is named Greencube or IO-117. Here’s some more information about Greencube from the S5Lab Research Team:

GreenCube is a 3U CubeSat aimed at demonstrating an autonomous biological laboratory for plants cultivation on-board a CubeSat platform. The satellite project is managed by the S5Lab research team at Sapienza University of Rome and it involves ENEA (the Italian National Agency for New Technologies, Energy and Sustainable Economic Development) and University of Naples “Federico II”. The project is coordinated by the Italian Space Agency (ASI) and it has benefitted of a launch opportunity offered by the European Space Agency. The spacecraft has been launched on-board the maiden Vega-C flight on 13 July 2022 and it has been deployed in Medium Earth Orbit (MEO) at approximately 5800 km of altitude. GreenCube is carrying microgreens (brassicacae) seeds for the farthest experiment ever of plants cultivation in microgravity.

Amateur Radio Payload

In addition to its scientific payload, Green carries an Amateur Radio digipeater that operates on the 70 cm band. The Digipeater operates in both real-time and store and forward modes.

Typical Greencube (IO-117) Pass Providing DX Possibilities

Typical Greencube Pass Providing DX Possibilities

The satellite’s MEO orbit provides passes lasting as long as 90 minutes and some great DX contact opportunities for Amateur Radio satellite operators. The image above shows a typical Greencube pass in the Northeastern US. The tracking program is MacDoppler, and the red arc shows the area on the ground that we can contact. This pass provides DX contacts to China, Asia, Hawaii, Alaska, the US, and Mexico. We can also reach much of Europe, the Middle East, Africa, and South and Central America via Greencube.

Greencube Contact QSL Card - JR6QFV/9

Greencube Contact With JR6QFV/9

To date, I have made about 320 contacts using Greencube, including DX contacts to Japan, China, Hawaii, Central and South America, the Caribbean, Europe, the Middle East, Africa, and many stations in the US.

Operating with Greencube – What’s Required

Greencube requires the following for successful contacts via its digipeater:

  • A directional antenna with at least 12 dBi gain
  • A 70cm SSB/FM capable Transceiver with a soundcard interface and at least 25 watts of output at the antenna
  • Software to control the Transceiver to correct for Doppler shift and provide antenna tracking control or pointing information
  • A computer running modem software and a Greencube Client Program
  • A low-noise preamp at the antenna is recommended
Satellite Antennas On the Tower - Tracking

Satellite Antennas On the Tower – Tracking

Space Communications Ground Station at AB1OC-AB1QB

Space Communications Ground Station at AB1OC-AB1QB

The ground station at our QTH more than meets these requirements.

Transportable Satellite Antenn

M2 Antenna Systems LEO Pack Transportable Satellite Antenna System

We are also testing our Transportable LEO Pack-based station with Greencube, and we’ll have more on the results from these tests soon.

More to Come

I am planning a series of articles covering setup and operations with Greencube in hopes that other Amateur Radio satellite operators might take advantage of this bird:

You can read more about our Satellite Ground stations here.

Fred, AB1OC

6m Antenna Upgrade Part 5 – Antenna Installation and Station Integration

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6m Antennas on our Main Tower

The final stage of our 6m Antenna Project was completed earlier this week. I began by gathering all of the hardware and components for the installation and staged them near our tower.

Project Components Ready for Installation

The installation of our new 6m antennas was a big project, and I was fortunate to have Matt Strelow, KC1XX, and Andrew Toth of XX Tower here to do the installation. We had many things go well during this project, and some good luck on a few items where we needed it.

Rearranging Antennas for the 7-Element LFA

The first step in the installation was to rearrange the antennas on the mast on our main tower. We moved our existing 2m yagi up to make space for the new 7-Element LFA yagi and installed it on our mast. We pulled the new LFA yagi about 30 ft above the ground on a tram line to check the SWR and adjusted the driven element before installing it on the mast.

New 7-Element LFA Yagi on Tower

New 7-Element LFA Yagi on the Tower

The first bit of luck was that we had enough rotator loop slack for our existing 2m yagi to move it up our mast about 4 ft without making a new feedline.

Removing 6m Elements from SteppIR’s

6m SteppIR Element Removal

SteppIR 6m Passove Element Removal

Our SteppIR yagis had 6m passive elements installed, and my modeling indicated that these elements would upset the pattern and performance of the new 6m yagis we are installing. Matt and Andrew came to the rescue on this one – they used an aluminum ladder rigged, as shown above, to remove the passive elements from both SteppIR yagis without taking them down. Note to our readers – do not try this a home!

Building the 6m Stacks

6m West Stack and 7 Element LFA

The next step in the project was to install the eleven 3-element LFA yagis that make up our new 6m stacks. This took some time as we had to work out and adjust mounting heights and the separation between the antennas in the stacks to avoid interference with guy cables, wire antennas, and other components on the tower. Andrew and Matt worked from the top of the tower to avoid climbing around the antennas after they were installed. At the end of the first day, we had the West-facing 3-stack installed on the tower.

All Eleven 6m Antenna Stack Installed

All Eleven 6m Antenna Stack Installed

The photo above shows the additional stacks facing Europe (on the left) and the south (on the right). With all the antennas installed, we were ready for the Power Dividers, feedlines, and electronics.

Feedlines, Electronics, and Switching

Hardline and Control Conduits

We used 1 5/8″ hardline coax for the main feedline from our shack to the 6m switching and electronics on our tower. I had previously installed conduits running from our tower to the shack, and we were able to get the new 1 5/8″ down the 100 ft conduit from our tower to the shack. The new hardline was added to the conduit (front left), which already had two 7/8″ hardlines in it. This part of the installation went smoothly, which was our next bit of good luck.

Hardline Connector Installation

Next, Matt installed N connectors on the new hardline. The photo above shows the hardline prep for the connector installation.

N Connector on the Main Feedline to Shack

N Connector on the Main Hardline to Shack

The photo above shows the completed connector installation.

Power Divider Installed on Tower

Power Divider Installed on Tower

The next step was to install the Power Dividers near the middle of each stack and hook up the phasing lines from the antennas. The photo above shows how the Power Dividers are mounted. We also ran 7/8″ hardline coax cables from the 7-element LFA yagi and from the Power Divider for the West stack on the top half of our tower down to the location where the Preamplifier Housing and Remote Antenna Switch is installed.

6m Preamp Housing and Antenna Switch Main Tower

The final step of the installation was to install the Preamplifier Housing and Remote Antenna Switch near the center of the bottom two stacks and hook all of the components up via LMR-400 coax jumpers.

Control Cable Interconnects on the Tower

Our tower has junction boxes installed at the base for interconnecting the many control cables for our antennas and electronics. It was a simple step to hook up the new Preamp Housing and Remote Antenna Switch to get everything working with our microHam control system. These junction points make it easy to rearrange and test our equipment on the towers when needed.

Updates on our VHF Tower

6m Preamp System on our VHF+ Tower

6m Preamp System on our VHF+ Tower

I built a second Preamp Housing for use with the existing 7-element 6m yagi on our VHF and Satellite Tower, and we installed that unit as well.

Control Cable Interconnect on our VHF+ Tower

Control Cable Interconnect on our VHF+ Tower

The junction box on this tower made the final hookup of the second Preamp Housing a snap.

Final Integration

We adjusted the length of the jumpers between the Power Dividers and the Remote Antenna Switch to optimize the SWRs of the stacks and tested all of the electronics on both towers via our microHam system. The stacks and the new 7-element LFA have SWRs at 1.3:1 or lower in the weak signal section of the 6m Band.

With everything connected and checked out, it was finally time to see what our new 6m Antenna System could do!

Initial Contacts

The Taurids Meteor Shower is active right now, so I’ve been making many Meteor Scatter contacts using our new antennas. The PSKreporter snapshot shows where I was heard this morning using MSK144 mode and the West antenna stack.

PSKreporter – 6m Meteor Scatter Reports

The background noise levels on the new antennas are between 3 dB and 9 dB, better than my previous 6m antennas were. This makes working weaker stations much easier to do.

We have not had much Es propagation since we finished the project earlier this week. I did catch a marginal Es opening yesterday and made an FT8 contact with CE8EIO in Chile. This contact is about 29,350 km from our QTH here in New England. It is the longest 6m contact I have ever made with South America.

PSK Reporter - CE8EIO Contact

PSKreporter – CE8EIO Contact in Chile

As you can see from the PSKreporter data, I was heard very well at CE8EIO. This is very encouraging. I have been making FT8 contacts with the midwest and the southeast United States using the new antennas as well. Given the very limited Es propagation at this time, I would say that the new antennas are a significant improvement.

More About our Project

Here are some links to other articles in our series about our 6m Antenna Upgrade Project:

We have completed all the steps in our 6m Antenna Upgrade Project. I look forward to the Winter Es period to see how well everything will perform. I plan to post more information about the performance of our new antennas once we have some better Es openings.

Fred, AB1OC

6m Antenna Upgrade Part 4 – Building Antennas and Prep for Installation

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First 3 Element LFA Antenna on the Tower

First 3 Element LFA Antenna on the Tower

Our new Loop Fed Array (LFA) antennas, phasing lines, and power dividers have arrived from InnoVAntennas. Our plan for this phase of our project includes the following steps:

  • Build mounts for the stack Power Dividers
  • Design and a mounting and truss system for the 3 Element LFA yagis in our stacks
  • Build the first 3-element LFA yagis, test mount it on our Tower, and adjust the SWR
  • Build the additional ten 3-element LFA yagis
  • Build the 7-element LFA and adjust its SWR

Power Dividers

We are using Power Dividers from InnoVAntennas to construct our three new fixed stacks.

4-Port Power Divider for 50 MHz

4-Port Power Divider for 50 MHz

These units are very well made and perform well, but they did not come with a system to mount them on our tower. I decided to fabricate mounting clamps to attach the Power Dividers to the legs of our tower.

Custom Power Divider Mounting Clamp

Custom Power Divider Mounting Clamp

The clamps are made using stainless steel U-clamps and 1″ square aluminum tubing.

Power Divider Mount Test

Power Divider Mount Test

The mounts worked out quite well, allowing easy access to the connectors on the Power Dividers for attaching coax cables. I made up three sets of clamps to mount the power dividers in our stacks.

3-Element LFA Mounting System

The 3-Element LFA antennas that we are using are a custom variation of InnoVAntennas 3-element LFA design. The antennas are designed to be rear-mounted to a pair of legs on a rotating tower. We are using the antennas on a fixed tower, and we want to be able to adjust the direction they point in. To accomplish this, I decided to fabricate an adjustable system suggested by Matt Strewlow, KC1XX, using a 1/4″ threaded stainless steel rod.

3 Element LFA Mounting System Mock Up

3 Element LFA Mounting System Mock Up

I began by assembling the boom and clamps for one of the 3-element LFA antennas and attaching it to our tower. This allowed me to fabricate and test an adjustable rear clamp to orient the antennas. The clamps and hardware are made from aluminum and stainless steel. The components came from DX Engineering and our local hardware store.

Adjustable LFA Antenna Mounting System

Adjustable LFA Antenna Mounting System

The final step in this part of the project was to install a small eye bolt near the front of the booms and create a simple clamp to attach a boom truss (dacron) rope and a turnbuckle to support the front of the antennas.

Boom Truss Attachment Clamp

Boom Truss Attachment Clamp

Once everything fit and worked properly, I made up 11 sets of mounting hardware to support all of our 3-element LFA yagis.

3-Element LFA Assembly and Test

The next step was to assemble the first 3-Element LFA yagi. These antennas are well-made and go together easily. I assembled the boom, mounting attachments, and the center of the elements in my shop and then moved the antenna outdoors to complete the assembly and final adjustments.

3 Element LFA Assembly

3 Element LFA Assembly

I attached and sealed the phasing lines to the driven elements and checked the SWR with the antenna pointing skyward. Next, I adjusted the length of the driven element loop ends to get each antenna’s SWR where I wanted it.

First 3 Element LFA Antenna on the Tower

First 3 Element LFA Antenna on the Tower

I mounted the first antenna on the tower to confirm that my mounting system worked as planned and to check the SWR adjustment with the antenna at its installed height above ground.

First 3 Element LFA Antenna - Installed SWR

First 3 Element LFA Antenna – Installed SWR

As you can see from the analyzer image above, the antenna tuned up very well.

6m Antenna Farm

The only real problem I encountered was finding enough space to store all 11 antennas after they were assembled and tested. As you can see from the photo above, we had quite an “antenna farm” in our backyard during this part of our project.

7-Element LFA Assembly and Test

The final part of this phase of the project was to assemble the new 7-element LFA yagi. This antenna uses a curved reflector to further improve its pattern and lower its noise temperature.

7 Element LFA - Boom and Element Centers

7 Element LFA – Boom and Element Centers

I had just enough room in our workshop to assemble the antenna’s boom, mast clamp, truss components, and element centers.

7 Element LFA - Final Assembly

7 Element LFA – Final Assembly

I moved the antenna outdoors, where we had more room to complete the final assembly, and attached the feedline. I adjusted the SWR of the antenna with the front elevated skyward. Final SWR and driven element adjustments were made with the antenna suspended about 30 ft above the ground on a tram line.

Next Steps

The final step in our preparations was to run control cables from our shack to the junction box on our towers to enable our microHam system to control the remote Preamp Housing and Antenna Switch.

The next step in our project will be to install everything on our towers and integrate all the antennas and components into our station.

We’ll continue to post more articles in this series as our project proceeds. Here are some links to other articles in our series about our 6m Antenna Upgrade Project:

With all of our preparations complete, we are ready to install our new antennas on our tower.

Fred, AB1OC

6m Antenna Upgrade Part 3 – microHam Antenna Control System

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6m Antennas choices on the Station Master Deluxe

6m Antenna choices on the Station Master Deluxe

The next step in our project is to configure our microHam station management system to support the new antennas and other components in our 6m antenna project. Each radio in our station (we have five that are 6m capable) has a microHam Station Master Deluxe antenna controller that is used to select and control all of our antennas. These units use the band selection and frequency data from their associated Transceivers to present a set of antenna choices and associated rotator, LNA, amplifier, and other controls to the user.

We are adding the following components to our 6m antenna farm that will need to be controlled by our microHam system:

Any of these antennas and their associated Preamp Housings can be used by any of the six Transceivers in our station. There are also two Elecraft KPA-1500 1500w amplifiers (one is shared) that operate on 6m and can be used by three of the five Transceivers in our setup. In this article, I will cover the configuration of our microHam system to support all of the new elements.

Remote Antenna Switching

microHam TEN SWITCH

microHam TEN SWITCH

I choose a microHam TEN SWITCH to handle switching between the new 7-Element LFA and the 6m Antenna Stacks that we will be installing. This switch is can be mounted outdoors on our tower and has good SWR, power handling, and loss performance at 50 MHz. I also chose the option to have N-connectors installed on our TEN SWITCH.

Control Interface Installation

microHam Control Boxes - Relay 10 (Remote Ant. Switch) & Relay 6 (Preamp Housings)

microHam Control Boxes – Relay 10 (Ant. Switch) & Relay 6 (Preamp Housings)

The first step in this part of our project was to install two new microHam Control Boxes to control the new remote antenna switch and the two 6m Preamp Housings. These control boxes are connected to a control bus which allows the Station Master Deluxe antenna controllers associated with our transceivers to control all of our equipment and antennas. The microHam TEN SWITCH that we are using requires ten 12 Vdc control lines to select one of its ten antenna inputs. Each of the two 6m Preamp Housings requires a combination of two 28 Vdc control lines to manage its relays and a 13.8 Vdc line to power its LNA. The microHam Relay 10 Control Box is a good choice for controlling the antenna switch, and a single microHam Relay 6 Control Box can be configured to control the two Preamp Housings. I installed the two new control boxes and a DIN Rail Terminal Block for ground fan out on an existing section of DIN rail in our shack. Finally, I extended the microHam control bus to the new units and connected the control boxes to the 13.8 Vdc and 28 Vdc power systems in our shack, and set the addresses of the two new control boxes.

Relay 10 (Ant. Switch) and Relay 6 (Preamp Housing) Control Box Configuration

Relay 10 (Ant. Switch) and Relay 6 (Preamp Housing) Control Box Configuration

Next, we updated the firmware in the new Control Boxes. We configured their relays into groups for interfacing to the remote microHam TEN SWITCH and the components in the 6m Preamp Housings.

New Antenna and Remote Switch Configuration

microHam Ten Switch on Tower

microHam Ten Switch on Tower

The next step was to define “RF Boxes” in the microHam program for the 7-Element LFA, three fixed-direction 3-Element LFA Antenna Stacks, and the two 6m Preamp Housings that we are going to be installing on our towers.

With this done, we created an additional RF box for the microHam TEN SWITCH that will be located on our main tower. The image above shows how the switch is configured in the microHAM system. We also needed to associate the Relay 10 control box with the switch to enable the microHam system to control it.

6m Preamp Housing Configuration

6m Shared Preamp Housing.jpg

6m Shared Preamp Housing.jpg

The next step was to configure our 6m Preamp Housings. The image above shows the configuration of the shared housing installed on our main tower behind the microHAM TEN SWITCH.

Antenna Switching Matrix

Station Antenna Switching Matrix

The shared Preamp housing will be connected to one of the inputs on our antenna switching matrix shown above.

This arrangement allows us to use the 6m LNA in the housing with any of the 3-Element LFA antenna stacks or the 7-Element LFA antenna we are installing on this tower. One of the features of the microHam system is that it can understand and correctly sequence shared devices like LNAs, amplifiers, and other active RF components.

LNA Controls

Preamp Housing LNA Control

Preamp Housing LNA Control

The image above shows the configuration for the LNA control button that will appear on our SMDs. The configuration above creates a button and display to turn the LNA on or off when an associated button on one SMDs is pressed. This control will appear on the SMDs for any radio using one of the associated 6m antennas.

LNA and PTT Sequencing

Preamp Housing Sequencer

Preamp Housing Sequencer

We also need to configure a sequencing element for each of our 6m Preamp Housings. This ensures that the Push To Talk (PTT) lines and transceiver inhibit lines are properly sequenced for the transceivers, amplifiers, and relays in the Preamp Housing that is part of a path to a selected antenna. The microHam system automatically applies the appropriate timing and sequencing rules to all of the RF elements in the path based on the sequencer settings shown above. Configuring the sequencer also involved associating the appropriate relay control units on the newly installed Relay 6 Control Box with the elements in the sequencer timing diagram above. One item to note here is the 20 – 30 ms tail on the sequencing of the Preamp Housing relays when going from Transmit to Receive. This is done to allow extra time for any stored RF energy in the feedlines during high-power Tx to dissipate before bringing the LNA back into the feedline system.

We also added our second 6m Preamp Housing to the RF path for our existing 7-Element M2 Antenna on our VHF Tower and configured it similarly.

Virtual Rotator for Fixed Antenna Stacks

6m Antenna Stacks - microHam Virtual Rotator

6m Antenna Stacks – microHam Virtual Rotator

The microHam system has a Virtual Rotator feature which is a great way to control selecting between fixed stacks of antennas of the type we are installing. The image above shows the Virtual Rotator we configured for our 3-Element LFA stacks. The Virtual Rotator becomes an additional antenna choice that accepts a direction in the same way that a conventional rotator does. The microHam system figures out which of the available stacks would best match any heading selected and automatically switches the antenna path to the stack that best matches the chosen heading. This capability will be a great tool in VHF contests when we are working multiplier grids on 6m.

microHam Control App - 7-Element LFA, shared LNA, and Rotator Controls

microHam Control App – 7-Element LFA, shared LNA, and Rotator Controls

Final Testing

With all the configuration work done, I downloaded the final microHam program to all of our Control Boxes and SMDs and did some more testing. I connected one of our 6m Preamp Housings to the newly installed Relay 6 Control Box and tested the operation with our Transceivers. Everything worked as expected.

I also used the microHam Control App (shown above) to test the various combinations of 6m antenna selections and configured options. The image above shows the selection of the new 7-Element LFA we are adding. Note the availability of controls for the LNA in the shared Preamp Housing and the controls for pointing the antenna via the associated rotator.

Virtual Rotator for 6m Stacks

Virtual Rotator for 6m Stacks

The image above shows the selections and controls for the 6m Antenna Stacks. The Virtual Rotator choice (STK-VR) is selected in this example. Each SMD has a control knob that can be turned to any heading. When the heading for the STK-VR antenna choice is changed, the system automatically chooses the stack that most closely matches the chosen direction. Choices are also available to choose any of the three stacks directly (ex. EU-STK for the LFA stack facing Europe).

microHam Control App - 6m Split Tx and Rx Antennas

microHam Control App – 6m Split Tx and Rx Antennas

Another nice feature of the microHam system is its ability to use different antennas for Transmit and Receive. The example above shows a setup that uses two different antennas for Tx and Tx.

As you can probably tell, the microHam Station Master Deluxe (SMD) system provides many features for controlling complex antenna arrangements and shared equipment. You can learn more about the microHam SMD system and what it can do here. You can learn more about the programming and operation of the SMD components via the SMD manual.

Next Steps

We’ll continue to post more articles in this series as our project proceeds. Here are some links to other articles in our series about our 6m Antenna Upgrade Project:

Our new LFA antennas and supporting equipment have arrived. The next step in our project will be assembling them and creating an adjustable mounting system for the 3-Element LFA antennas in our stacks.

Fred, AB1OC