A Portable Satellite Station Part 6 – Plans for a 4.0 Station

Portable Satellite Station 3.0 Antenna System

Satellite Station 3.0 Antenna System

We have begun looking ahead to Satellite Station 4.0 and where we want to go next after our ARISS crew contact is complete. Our goals for the Satellite Station 4.0 include:

  • A permanently installed version of our 3.1 Station which can be operated remotely over the Internet
  • Upgraded Transceivers which add Pan Adapter/Waterfall display capabilities
  • Enhancements to our Transportable 2.1 Station for improved performance
  • A more portable version of our 1.1 Station for Grid Square Activations

New 4.0 Station at our Home QTH

The performance of the 3.1 Station’s antennas is very good but the antenna system is a handful to transport. We are planning to install these antennas on a new tower at our QTH and use our Flex-6700 SDR-based Remote Operating Gateway with some upgrades to create a remotely controlled satellite station which can be operated via the Internet. The main components of the 4.0 Station will include:

The new tower will also provide a new antenna system for the 6 m band.

Updated Remote Operating Setup

Flex-6700 SDR-Based Remote Operating Setup

The Flex-6700 SDR and the associated Maestro Remote Unit will enable the 4.0 Station to be remotely operated through the Internet via a Laptop running MacDoppler.

Upgraded Transportable 2.2 Station

Upgrade plans for our Transportable station include the addition of remote switchable polarity relays and a new Icom IC-9700 Transceiver when it becomes available.

Polarity Switch Installed in LEO Pack Antennas

Polarity Switch Installed in LEO Pack Antennas

The polarity switches have been installed on the M2 Antennas 436CP16 and 2MCP8A antennas in our M2 Antennas LEO Pack. We are using a DX Engineering EC-4 console to control LHCP or RHCP polarity selection on the antennas. We have been doing some testing with the upgraded LEO pack which includes the polarity switching capabilities and we are seeing a significant improvement in performance.

Alfa Spid Az-El Rotator

AlfaSpid Az-El Rotator

We are also planning to move the upgraded LEO pack antennas to the current 3.1 Tower to take advantage of the AlfaSpid Rotator which is installed there.

Icom IC-7900 Transceiver

The other major upgrade planned for the 2.2 Station is the new Icom IC-9700 Transceiver when it becomes available. This radio will utilize Icom’s SDR platform and includes a Pan Adapter/Waterfall display which will be a very useful addition for operation with Linear Transponder Satellites.

Upgraded Portable 1.2 Station

We really enjoy mountain topping and activating grid squares so we are planning upgrades to our 1.2 Station for this purpose.

Our 1.2 Portable Satellite Station on Mt. Kearsarge

Our 1.2 Portable Satellite Station on Mt. Kearsarge

The 1.2 Station utilizes computer control to enable operation with linear transponder satellites and will use solar/battery power along with a 100w/70w Icom IC-910H Satellite Transceiver.

Solar Panels

Solar Panels

A pair of 90W foldable solar panels, an MPPT solar charger, and a pair of LiPo 4S4P A123 batteries provide plenty of power to run the IC-910H Transceiver and the associated computer. The portable station also includes a pair of ARR preamps.

Portable Satellite Antenna System

Portable Satellite Antenna System

The antenna system we’ll be using is an Elk Portable Log Periodic 2m/70cm yagi on a camera tripod. A combination of a compass and an angle finder gauge help us to correctly point the antenna.

As you can probably tell, all of these upgrades are in progress and are at various stages of completion. We will post updates here on our Blog as we continue to make progress.

Fred, AB1OC

Nashua Area Radio Society Youth Expo at Boxboro

Karen KC1KBW a BGHS Teacher Building a Kit

Karen KC1KBW a BGHS Teacher Building a Kit

The Nashua Area Radio Society put together a successful Amateur Radio Youth Exposition at the New England Amateur Radio Convention at Boxboro this year. Our exposition features over ten displays with hands-on activities…

Source: NARS Youth Expo at Boxboro – Nashua Area Radio Society

Anita AB1QB and I are continuing to work along with the Nashua Area Radio Society to encourage young people to become licensed and join the Amateur Radio Service.

NARS Team at Boxboro

Nashua Area Radio Society Team at Boxboro

The Nashua Area Radio Society recently hosted an Amateur Radio Exposition for Young People at the New England Amateur Radio Convention in Boxboro, MA. Our event featured Remote HF and Satellite GOTA stations, a kit build, and many other hands-on activities which were part of the over ten displays at the event.

You can read more and see photos from our Youth Expo via the link above. We will be holding another Amateur Radio Youth Expo as part of NETT at NEAR-Fest in Deerfield, NH in October. We hope to see some of our local friends there.

Fred, AB1OC

Working IC-9700 Shown In Tokyo

Working IC-9700 On Display In Tokyo

Working IC-9700 On Display In Tokyo

Icom displayed three working demonstration units of the forthcoming IC-9700 VHF/UHF/1.2GHz transceiver, Icom Inc. at the Tokyo Hamfair, which took place in Ariake, Tokyo on August 25th – 26th.

Source: New Icom Amateur Products Shown at Tokyo Hamfair 2018

The IC-9700 is a new VHF/UHF radio that is based upon the Software Defined Radio (SDR) platform that Icom uses in the IC-7300 and IC-7610.

It looks like this is going to be an excellent radio for Satellite, EME, and other weak-signal work on the 2 m, 70 cm, and 23 cm bands. The IC-9700 features a pan adapter display which will be very useful for working contacts through linear satellites.

Based upon previous new Transceivers release by Icom, I would guess we are at least 8 months to a year away from the time when this radio will be offered for sale in the USA.

Here’s some video of the forthcoming  IC-9700 as well as other gear from Icom. The video also features other new products and updated Firmware capabilities from Icom. Enjoy!

Fred, AB1OC

Sights from the New England Tech Trek (NETT) at NEAR-Fest

We have been working on project to scale our open house activities to provide an opportunity to learn about Amatuer Radio and to showcase some of the modern, “hi-tech” aspects of the Amatuer Radio Service. This project was debuted at the NETT event at NEAR-Fest. We used our Portable Satellite Station, Remote Operating Gateway, and our Mobile HF Stations as part of this activity. There might be some ideas here that you can use to create an exciting operating activity at you local club or Ham Fest.

Source: Sights from the New England Tech Trek (NETT) at NEAR-Fest

Upgrading our 2.0 Satellite Station for ARISS Contacts

We have been working with Hudson Memorial School near Nashua, NH to prepare for a possible ISS crew contact. The ARISS folks work with schools and their Ham Radio helpers to prepare for these contacts. ARISS provides recommendations for ground station equipment to help ensure a good experience for the students. The ground station recommendations provide a solid set of specifications to support communications with the ISS on the 2m band. The recommendations include things such as:

  • A requirement to build both a primary and a backup ground station
  • Radio and power specifications (a 200W amp is recommended)
  • Antenna specifications including recommendations to provide for switchable LHCP and RHCP
  • Computer controlled azimuth/elevation positioning of antennas to track the ISS
  • Use of a receive preamplifier at the antenna
Portable Satellite Station 3.0 Antenna System

Portable Satellite Station 3.0 Antenna System

We have recently completed construction and testing of our Portable Satellite Station 3.0 which was built specifically to meet the primary station requirements for our ISS contact.

Our plan is to add some upgrades to our Portable Satellite Station 2.0 to create a Portable 2.1 Station which meets the backup station requirements. These upgrades will include:

All of the equipment needed to upgrade our 2.0 Portable Station to 2.1 is either here or will arrive shortly. Here’s some more information on the planned equipment.

Icom IC-910H Transceiver

Icom IC-910H Transceiver

The Icom IC-910H was Icom’s flagship Transceiver for Satellite work before the IC-9100 was released. It’s a very nice satellite radio! Dave, K1DLM graciously lent us his IC-910H for use in our backup station.

Green Heron RT-21 AZ/EL Rotator Controller

Green Heron RT-21 AZ/EL Rotator Controller

We already have a Green Heron Az/El Rotator controller setup for the Yaesu Rotator system on the 2.0 Antenna Tower and we will be reusing it for the 2.1 station.

GHTracker Running On A Raspberry Pi 3

GHTracker Running On A Raspberry Pi 3

We are also planning to build a second Raspberry Pi Rotator Interface for it.

M2 Antenna Systems PS2MCP8A Polarity Switch

M2 Antenna Systems PS-2MCP8A Polarity Switch

M2 Antenna Systems recently added a new 2M polarity switch, the PS-2MCP8A, designed for use with the 2M antenna in their LEO Pack which we are using in our 2.0 Antenna System. We will be installing this relay as well as a PS-70CM polarity switch relay for the LEO pack’s 70cm antenna as part of the 2.1 Antena System upgrade.

DXEngineering EC-4 Control Box

DXEngineering EC-4 Control Box

We will add another DXEngineering EC-4 BCD Control Console to control the polarity switching relays on the upgraded antennas.

m RM ITALY LA-250V Amplifier

RM ITALY LA-250V Amplifier

The final new component in our 2.0 to 2.1 upgrade is the addition of a 200W RM ITALY LA 250 power amplifier. We have opted for the version of this amplifier with the cooling fans. The unit is very well made and we are anxious to see how it performs on the air.

Some of our readers might be wondering what we are planning to do with all of Portable Satellite Ground Station equipment in the long run? We plan on keeping the 1.0 Portable Station for grid square activations and demonstrations. Its simple, battery-powered approach and small antenna make it ideal for this sort of work.

The upgraded 2.0 Portable Station with its enhanced polarity switching will become our transportable station for License Class and Field Day use. It will be converted at the end of 2018 to use our Icom IC-9100 Transceiver that is currently part of the 3.0 station.

We plan to use the Portable 3.0 Station through the year (2018) to support the planned ARISS contact, Field Day, and some demonstrations at local Ham Fests and schools. Once these are complete, we plan to permanently install it here at our QTH and it will become our main satellite ground station at our home QTH.

You can view all of the articles about our Portable Satellite Stations via the links below.

We will begin construction of the 2.1 upgraded station once a few remaining components arrive here. We plan to share some more about the construction and initial testing of our 2.1 Portable Station here.

Fred, AB1OC

A Portable Satellite Station Part 6 – 3.0 Station Initial Contacts

Tech Class First 3.0 Portable Station Test

Tech Class First 3.0 Portable Station Test

With the construction of our Portable Satellite Station 3.0 complete, we’ve been looking forward to an opportunity to test the new setup. We chose the Nashua Area Radio Society’s recent Technician License Class as a good time to both test the new stations and to acquaint our Tech Class grads with one of the many things that they can do with their new licenses – amateur satellite operations.

Tech Class 3.0 Portable Satellite Antenna Test

Tech Class 3.0 Portable Satellite Antenna Test

The first transport of the new 3.0 station antenna system turned out to be simple. The booms and counterweights of the new antenna system are easily separated via the removal of a few bolts located at the cross-boom. This allowed the antennas feed-points, rotator loops and polarity switching connections to be removed and transported as complete assemblies. The separation of the longer-boom antennas into two sections also made transporting the antennas easier and made the antenna elements less prone to bending in transport. Setup and cabling of the new 3.0 antenna system as the class site was quick and simple.

The opportunities to make contacts during our Tech Class were limited but the new system performed well with one exception. We saw a higher than expected SWR readings on the 70cm yagi during transmit. We immediately suspected problems with one of the N connectors that were installed during the construction of the new system (component testing during assembly showed the SWR readings on the 70cm side of the system to be in spec.).

Portable Satellite Station 3.0 Antenna System

Portable Satellite Station 3.0 Antenna System

After the class, we set up the 3.0 system again at our QTH. Transport and re-assembly of the new system are somewhat easier and faster than our 2.0 portable station antenna setup is.

Satellite Antenna System 3.0 Connections

Satellite Antenna System 3.0 Connections

The 3.0 antenna system uses a similar connector bulkhead approach that we used previously. The rotator controls are handled via a single, 8-conductor cable and we have a new connection for the polarity switching controls on the 3.0 system yagis.

Rotator Loop Coax Retention System

Rotator Loop Coax Retention System

We have had some problems with the connections between the preamplifiers mounted at the antennas and the rotator loops which connect the antennas to them. This problem caused several failures in the associated N-connectors on the 2.0 portable antenna system so we fabricated a simple arrangement to prevent the rotation of the antennas from turning the coax inside the N-connectors and causing these failures.

70cm Yagi SWR in the Satellite Sub-Band

70cm Antenna and Feedline SWR in the Satellite Sub-Band

Some isolation tests were performed on each cabling element of the 70cm side of the 3.0 antenna system and this resulted in the location of an improperly installed N-connector. The faulty connector was easily replaced and this corrected the SWR readings on the 70cm side of the antenna system. The image above shows the SWR readings for the 70cm antenna after the faulty connector was replaced. We checked the SWR performance with the 70cm yagi set for both Left-Hand and Right-Hand Circular Polarization and we saw good results in both configurations.

2m Yagi SWR in the Satellite Sub-Band

2m Antenna and Feedline SWR in the Satellite Sub-Band

We also re-checked the SWR performance of the 2m side of the antenna system with the 2m yagi in both polarity settings and it looked good as well.

Portable Satellite Antenna 3.0 Az-El Rotator

Portable Satellite Antenna 3.0 Az-El Rotator

The 3.0 antenna system uses an Alfa-Spid rotator. The Alfa-Spid can handle the additional weight of the larger yagis and has a more precise pointing ability (1° accuracy) which is helpful given the tighter patterns of the larger, 3.0 yagis.

70cm Yagi Switchable Polarity Feedpoint

70cm Yagi Switchable Polarity Feedpoint

The new yagis in the 3.0 antenna system have feed point arrangements which allow the polarity of the yagis to be switched between Left-Hand Circular Polarity (LHCP) and Right-Hand Circular Polarity (RHCP). These antennas used a relay arrangement at the feed-points that flip the polarity of one plane of the yagis by 180° which in turn changes the polarity of the antennas between LHCP and RHCP.

Portable Satellite Station 3.0 Radio and Controls

Portable Satellite Station 3.0 Radio and Controls

With the SWR problem corrected, we set up the 3.0 station radio and controls. The 3.0 station adds our homebuilt PTT Router and the control box from DXengineering which controls polarity switching. Also, the Green Heron rotator control box has been configured to control the new Alfa-Spid rotator.

POrtable Satellite Station 3.0 Computer Control via MacDoppler

Portable Satellite Station 3.0 Computer Control via MacDoppler

We are continuing to use the excellent MacDoppler software to control the 3.0 station. MacDoppler provides tracking controls for the antennas and doppler correction for the Icom-9100 transceivers uplink and downlink VFOs.

Satellite 3.0 Station Control Details

Satellite 3.0 Station Control Details

The image above shows a closer view of the 3.0 station controls. The box in the middle-left with four LEDs and the knob is used to select one of four polarity configurations for the 2m and 70cm yagis – RHCP/RHCP, LHCP/RHCP, RHCP/LHCP, or LHCP/LHCP. Just to the right in the middle stack is our homebrewed PTT Router which expands and improves the PTT sequencing performance of the station.

So how does the new 3.0 station perform? The new antennas have a tighter pattern requiring careful pointing calibration of the rotators during setup. This is easy to do with the Alfa-Spid rotator. The new antennas have noticeable more gain as compared to the LEO pack used on the 2.0 station. We are also surprised to see how much difference the polarity switching capability makes in certain situations – sometimes as much as two S units (12 dB) in certain situations. The combination of the new antennas and selection of the best polarity combination allows solid operation on many satellites passes with as little as 2 watts of uplink power. We have made a little over 50 QSOs on the new 3.0 station so far and it works great! For more information on the Portable 3.0 Station as well as the 2.0 and 1.0 stations that we’ve built – see the links below:

Fred, AB1OC

 

PTT Router for Satellite Station 3.0

ARR Satellite Preamp

Advanced Receiver Research Remote Preamp

Our Satellite Station 2.0 antenna system uses a pair of Advanced Receiver Research Remote preamplifiers at the antennas to boost weak signals. These preamps have RF sensing and switching to protect them during transit. While this system works well; we are always concerned about the impact of the RF power affecting the long-term reliability of these devices and the associated radio equipment.

M2 Antenna Systems S3 Sequencers

M2 Antenna Systems S3 Sequencers

Our Satellite Station 2.0 uses a pair of M2 Antenna Systems S3 Sequencers to control the preamps remotely. For U/V and V/U mode satellites, it’s a simple matter to turn off the uplink band preamp to protect it against RF during transmit. The problem with this approach comes when working satellites and the International Space Station in simplex (single band) modes. In these situations, we need a solution which keys the sequencers externally so that the sequencers can properly control the changeover of the preamps from receive to transmit mode before keying our radio (an Icom IC-9100). We also wanted a solution which could also allow the radio initiate the keying of the sequencers for CW break-in keying and digital modes.

PTT Router

PTT Router

Our solution was to design and build a simple Push-To-Talk (PTT) router. This device allows an external source such as a footswitch or a trigger switch to initiate the keying. The design also includes indicators which confirm that the keying sequence has completed.

PTT Router Schematic Diagram

PTT Router Schematic Diagram

Our first step was to create a simple design which allowed for either an external switch or the radio to initiate keying. The PTT source switch (S1) selects the keying source and uses the Hsend  (2m key) and Vsend (70cm/1.2 GH key) lines on the Icom IC-9100 accessory jack as either the means to key the radio or the means to detect that the radio has initiated a transmit keying sequence. A second switch (S2) selects which VFO is keyed when the keying source switch (S1) is in External mode. Finally,  indicators for power and keying complete were added.

Rear Panel Connectors

Rear Panel Connectors

A small enclosure was used to house the switches, indicators, and the connections to the rest of our Satellite Station. The image above shows the rear-panel connections to external PTT sources, the S3 Sequencers, the IC-9100 Radio, and a 12 Vdc station power source.

PTT Router Internal View

PTT Router Internal View

A pair of terminal strips were mounted inside the enclosure to make connecting all of the components easier. The wiring is pretty dense around the front and rear panels so connections were insulated with heat shrink tubing. A small PCB could easily be created to make replicating the prototype easier should we decide to build more copies of the design.

Satellite Station 3.0 Controls

Satellite Station 3.0 Controls

Our new PTT router was easy to integrate into our Satellite Station 3.0 setup. Integration required some custom cables to be made to connect our PTT router to the sequencers and to the accessory jack of the radio. With the integration completed, we are now able to properly sequence the control of the preamps and the radio in all modes of operation. Here are some more articles which include more about our portable satellite stations –

Fred (AB1OC)

ISS Crew Contact

We have been working with Hudson Memorial School to help them secure and prepare for an ISS Crew Contact. We are hoping to support their ISS Crew Contact using an upgraded version of our Portable Satellite Ground Station. A school in Raleigh, North Carolina had their ISS Crew Contact today and I decided to record the downlink from the ISS to test our backup Portable 2.0 ISS/Satellite Ground Station.

The video above is a capture of the school’s contact. It was very easy to receive the ISS downlink on our portable backup ground station. I heard the downlink a few seconds before the ISS came up on the horizon and the audio was solid for the duration of the contact. We can only hear the astronaut’s side of the contact as we cannot receive the school’s uplink from Raleigh, NC. The ISS pass began here in New Hampshire part way through the school’s session so we did not hear the first few questions.

Update on Portable ISS/Sat Station 3.0

Portable ISS/Sat Station 3.0 Antenna System

Portable ISS/Sat Station 3.0 Antenna System

Work on our upgraded primary Portable 3.0 Station which includes a larger antenna system using switchable circular polarity is progressing well. The portable tower, upgraded rotator system, and the new, larger 2m and 70cm circularly polarized antennas are complete.  We are just waiting for a few additional components to arrive here and the upgraded portable ground station should be ready for its first test at our Technician License Class later this month.

More on Today’s ISS Crew Contact

You can see a live stream of the ISS Contact from the school above. There is a great deal of planning which goes into an ISS Crew Contact such as this. We are working closely with Hudson Memorial School on their project and their school is also beginning a High-Altitude Balloon Project with us in a few weeks.

The ISS Crew Contact today was exciting to listen too and we are looking forward to being able to share this experience with Hudson Memorial School in the near future.

Fred, AB1OC

Receiving SSTV From The ISS

Portable Satellite Station Additions - Digital and Packet

Portable Satellite Station With Additions For Digital and Packet

We’ve recently upgraded our Portable Satellite Station 2.0 to add digital and packet capabilities. The upgrade was pretty simple – we added a SignaLink USB Soundcard and a Windows Laptop PC. Most of the software for packet and digital Amateur Radio communications is written for the Windows OS so using a separate laptop running Windows 10 was the simplest way to go. Another benefit of the second laptop was added screen space to use when doing packet communications via satellites and the International Space Station (ISS).

SSTV Image From The ISS

SSTV Image From The ISS

We recently learned that the ISS was going to be again transmitting SSTV images worldwide. This provided a perfect opportunity to work with the digital additions in our satellite setup. We downloaded and installed MMSSTV on our Windows laptop and set the audio levels on the Windows PC and our SignaLink Sound card to properly receive SSTV signals. The MMSSTV application can decode several different SSTV formats including the PD120 format used by the ISS. The ISS transmits SSTV on a 2m FM voice channel. We configured MacDoppler to track the ISS and perform doppler correction on the 2m ISS 2m downlink and began to listen.

The video above was made during the reception of an SSTV image from the ISS during a pass over the United States. The video gives a good idea of what its like to receive SSTV from the space station.

Another SSTV Image From The ISS

Another SSTV Image From The ISS

We were able to receive several different images from the ISS during the period that it was transmitting SSTV worldwide.

A Third SSTV Image From The ISS

A Third SSTV Image From The ISS

It was pretty easy to capture the SSTV transmissions from the ISS with our Portable Satellite Station 2.0 setup. The signals were strong and I would imagine that the SSTV transmission could have also been received with a simple portable satellite setup with a hand-held yagi antenna.

We hope that the ISS will send SSTV images again in the near future. It was fun receiving them.

Fred, AB1OC