Portable Satellite Station Transceiver and Related Equipment

With the Antenna System for our 2.0 Portable Satellite Station complete, we turned our attention to assembling the Transceiver and supporting equipment. The equipment used for this part of the project includes:

• Icom IC-9100 Transceiver and SP-23 Speaker
• Green Heron RT-21 Azimuth/Elevation Rotator Controller (see Part 2 of this series for details on this device)
• M2 Antenna Systems S3 Sequencers for Preamp Control
• WaveNode WN-2 Wattmeter
• Powerwerx SS-30 DV 30A Power Supply and RigRunner 4007U distribution unit
• Heil Pro 7 Headset with Boom Microphone (desk microphone shown in the picture was used for testing only)
• Apple MacBook Air laptop running MacDoppler Satellite Tracking Software

The Icom IC-9100 provides 100W on 2M and 75W on 70 cm, which is more than enough power for our application. It also has some nice satellite features, such as support for synchronized VFO tracking between the radio’s 2M and 70 cm VFOs. This radio also uses a single USB connection to allow computer control of the radio and the creation of a sound card interface on the host computer. A Heil Pro 7 Headset will be used for operator audio to avoid feedback due to our audio coming back from the satellite. The Icom SP-23 speaker is included to allow observers to hear satellite contacts while they are in progress.

Radio Management via MacDoppler

The MacDoppler software provides automated control of the IC-9100, including mode selection and automatic correction of both VFOs for the Doppler shift. These features greatly simplify the operation of the radio, especially when satellites with SSB/CW transponders are used.

The video above shows MacDoppler’s management of the IC-9100 Transceiver during a pass of AO-73. The constant adjustments of the VFOs take care of Doppler shift correction and ensure that our signal stays at a fixed position in the transponder passband of linear transponder satellites.

Preamp Sequencers and Output Monitoring

M2 Antenna Systems S3 Sequencers are used to provide control of the Advanced Receiver Research low-noise preamps on our portable tower. One of the nice features of the Icom IC-9100 is that it can be configured to provide separate keying lines for the 2M and 70cm VFOs. This allows a preamp to remain enabled on the receive VFO while the other VFO is in transmit mode with its preamp shutdown by the sequencer. This arrangement is very useful during tuning when one needs to hear your signal coming back from a satellite. A custom-made cable assembly was made to interconnect the S3 Sequencers with the ACC socket on the IC-9100, the Weatherpack connector on the tower preamp control cable, and DC power.

We used the excellent WaveNode WN-2 Wattmeter again in our portable satellite setup. This modular output monitoring system has sensors for VHF/UHF use as well as voltage, signal quality, and other monitoring functions.

DC power for the setup is provided via a Powerwerx SS-30DV Power Supply and a RigRunner 40007U distribution unit. We use this power supply in all of our portable setups. It is lightweight, provides plenty of power for a 100W station and accessories, and is quiet from an RF perspective.

Equipment Packing and Protection

With the transceiver test of the station complete, we turned our attention to transporting the setup. Proper protection of the equipment during transport was provided via a large case from Pelican. We combined this with a roller bag and an inexpensive storage bin for documentation and accessories, which are not very fragile. We also included our RigExpert antenna analyzer in the setup to make testing the station during setup in a portable environment easier.

Station Packed and Ready for Transport

With all of the assembly and testing of our 2.0 Portable Satellite Station components complete, we packed up all the components. We used an inexpensive furniture dolly to allow us to roll the tower around to load and unload it.

We are ready to test our new station in a portable application. More on that in the final article in this series. Other articles in the series include:

• A Portable Satellite Station Part 1 – A Simple Station for AO-85
• A Portable Satellite Station Part 2 – 2.0 Station Goals and Antenna System
• A Portable Satellite Station Part 4 – 2.0 Station First Contacts!
• A Portable Satellite Station Part 5 – Plans for Our 3.0 Station
• A Portable Satellite Station Part 6 – 3.0 Station Initial Contacts
• Plans for Upgrading Our 2.0 Station for ARISS Contacts
• Raspberry Pi Satellite Rotator Interface
• Raspberry Pi Satellite Tracker Interface How To
• PTT Router for Satellite Station 3.0

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

Fred, AB1OC