EME Station 2.0 Part 2 – Excavation, Footings, and Conduits for New Tower

EME Tower

FInished Tower Base and Cable Conduits

The first part of our EME project is to put up a new tower to support our antennas. Our plans call for a 26′ tower built using three Rohn 55G tower sections. Four feet of the first section of the tower is cemented in a concrete footing to anchor the tower’s base. The tower is also going to be guyed to ensure that it is very stable.

EME Tower

Digging Footings for our New Tower

We are working with Matt Strelow, KC1XX and Andrew Toth of XX Towers to put up our new tower. Matt brought out his tractor and dug the footings for our tower and for the associated conduits that will carry coax and control cables to our shack. The photo above shows the completed hole and form for the main tower base. Matt is working on the footings for one of the three guy anchors.

EME Tower

First Tower Section and Rebar Cage

Here’s a closer look at the tower base. The footing includes a rebar cage to reinforce the concrete footing. There is also 6″ of crushed stone in the bottom of the hole that the tower legs sit it. It is very important that the bottoms of the tower legs remain open and do not become plugged with cement so that water in the legs can drain. If the legs cannot drain properly, water will accumulate and freeze. This can split open the tower legs and ruin the tower.

EME Tower

Cable Conduits with Drains

We also installed two conduits (a 4″ and a 2″ run of schedule 80 conduits) from the base of our tower to our shack. These conduits will carry coax feed lines and control cables to our new tower. We used a pair of 22° elbows to create a smooth transition to bring the conduits out of the ground. This will ensure that our hardline and other coax cables can be placed in the conduits without creating excessive bends.

Conduits will fill with water even if they are sealed. This happens as a result of the condensation of water in the air. To prevent our conduits from filling with water, we created two drain pits at the bottom of the trench at the two lowest spots in the conduit runs and filled them with stone. We drilled a few holes in the bottom of the conduits above the drain pits to allow the water to drain so our cables will remain dry.

EME Tower

Cadweld’ed Ground Cable Bonded to a Ground Rod

We also created a bonding ground cable run from our new tower to the ground system at our shack entry. The bonding system was created by driving an 8′ ground rod every 10′ in the trench between our new tower and the perimeter ground around our house.

#2 stranded copper ground cable was Cadweld’ed to each ground rod to create a ground path to bond the tower to the perimeter grounding system around our house. Using a Cadweld system is simple and produces strong connections that will not deteriorate.

Here’s a video that shows our a Cadweld is made. We’ll cover completing the ground connections to the tower and the perimeter grounding system in a future article.

EME Tower

Completed Footings – Ready to Pour Cement

Finally, we used some sections of rebar to firmly support the guy anchor rods prior to pouring the cement. If you look closely, you can see a portion of the rebar material in one of the guy anchor footings in the photo above.

EME Tower

Cement Mixer

The next step in this part of our project was to pour the cement. A large cement mixer brought the proper cement mix to our QTH and Matt used his tractor to transport the cement from the mixer to the forms. We did a bit of finishing work on the cement base for our tower and let the cement dry for a few days.

EME Tower

FInished Tower Base and Cable Conduits

The last step was to remove the forms and backfill the footings. A little work with a cement finishing block was done on the cement base to round off the rough edges left by the forms. The cable conduits emerge from the ground next to the tower base. You can also see one end of the copper bonding cable next to the conduits as well.

EME Tower

Completed Guy Anchor

Here’s one of the completed guy anchor rods after backfilling. We are going to let the cement harden for a couple of weeks and then we’ll complete the construction of our new tower.

Here are some links to other articles in our series about our EME Station 2.0 project:

Fred, AB1OC

EME Station 2.0 Part 1 – Goals and Station Design

The Moon

The Moon

EME or Earth-Moon-Earth contacts involve bouncing signals off the moon to make contacts. EME provides a means to make DX contacts using the VHF and higher bands. There are also some EME Contests including the ARRL EME Contest that provides opportunities to make EME contacts.

We made some 2m EME contacts a while ago using the 2m antenna on our tower at about 112′. This experience created interest on my part in building a more capable EME station at some point in time. Well, the time has finally arrived.

EME Propagation

Understanding EME Propagation is a project in of itself. The following is a brief overview of some of the (mostly negative) effects involved.

The path loss for EME contacts varies by Band and is in excess of 250 dB on the 2m band. There are some significant “propagation” effects that further impair our ability to make EME contacts. These include:

  • Faraday Rotation – an effect which results in the polarity of signals being rotated by differing amounts as they pass through the ionosphere on their way to the moon and back
  • Libration Fading – fading caused by the adding of the multiple wave-fronts that are reflected by the uneven surface of the moon
  • Path loss variations as the earth to moon distance varies – the moon’s orbit around the earth is somewhat elliptical in shape resulting in a distance variation of approximately 50,000 km during the moon’s monthly orbital cycle. This equates to about a 2 dB variation in total path loss. An average figure for the path loss for 2m EME might be in the range of 252 dB.
  • Transit Delays – at the speed of light, it takes between 2.4 and 2.7 seconds for our signals to travel from earth to the moon and back.
  • Noise – the signals returning from the moon are extremely weak and must compete with natural (and man-made) noise sources. The sun and the noise from other stars in our galaxy are significant factors for EME communications on the 2m band.
  • Doppler shifts – as the earth rotates, the total length of the path to the moon and back is constantly changing and this results in some frequency shift due to doppler effects. Doppler shift changes fairly slowly compared to the time it takes to complete a 2m EME QSO so it is not a major factor for the 2m band.
  • Moon’s size vs. Antenna Aperture – the moon is a small target (about 0.5 degrees) compared to the radiation pattern of most 2m antenna systems. This means that most of our transmitted power passes by the moon and continues into space.

Taking the moon’s size, an average orbital distance, and an average Libration Fading level into account, one can expect only about 6.5 % of the power that is directed towards the moon to be reflected back towards earth.

EME “Good Guys”

One might look at the challenges associated with making EME contacts and say “why bother”? EME contacts present one of the most challenging and technical forms of Amateur Radio communications. It is this challenge the fascinates most EME’ers including this one. Fortunately, there are some “good-guy” effects that help to put EME communications within reach of most Amateur Radio stations. These include:

  • WSJT-X and the JT65 Digital Protocol – In the early days of EME communications, one had to rely on CW mode to make contacts. All of the impairments outlined above made these contacts very challenging and the antennas and power levels required put EME communications out of the reach of most Amateurs. Along came Joe Taylor’s digital JT65 protocol which changed all of this. It is now possible to make 2m EME contacts with a single (albeit large) 2m yagi and 200W or so of input power. As a result of these innovations, many more Amateurs have built EME stations and are active on the 2m (and other) bands. Many DXpeditions are now also including EME communications in their operations.
  • Ground Gain Effects – a horizontally polarized antenna system will experience approximately 6 dB of additional gain when the antenna(s) are pointed approximately parallel to the ground. Ground gain effects made it possible for us to use our single 2m antenna to make our first 2m EME contacts.
  • MAP65 Adaptive Polarization – Fading resulting from polarity changes due to Faraday Rotator can cause a received signal to fade to nothing over the period of time needed to complete a 2m EME contact. These polarity “lock-out” effects can make contacts take significant time to complete. Fortunately, a version of the software which implements the JT65 protocol called MAP65 has been created that will automatically detect and adapt to the actual polarity of signals returning from the moon. More on how this is achieved follows below. MAP65 is most useful for making “random” EME contacts during contests. In these situations, a variety of signals will be present in a given band with different polarities and the MAP65 software can adapt to each one’s polarity and decode as many simultaneous signals as possible.
  • Commercially Available Amplifiers for VHF+ Bands – Modern, solid-state amplifiers have become much for available for the 2m (and other VHF and higher bands). This has made single-antenna EME on 2m and above much more practical for smaller stations with a single antenna.

Our 2m EME Goals and Station Design

We began this project by making a list of goals for our 2m EME Station 2.0. Here is that list:

  • Operation using JT65 and QRA64 digital protocols and possibly CW on the 2m EME band
  • 80th percentile or better station (i.e. we want to be able to work 80% of the JT65 capable 2m EME stations out there)
  • Operation in EME contests and EME DX’ing; earn a 2m EME DXCC

We have come up with the following station design parameters to meet these goals:

  • An array of four X-polarized antennas with an aggregate gain of approximately 23 dBi
  • A new 26′ Rohn 55G tower to support the antennas
  • A computer-controlled Azimuth/Elevation rotator system to allow us to track the moon
  • Input power in the range of 900W
  • A MAP65 capable SDR-based receive system which can support adaptive polarity
  • Low-noise, high gain preamplifiers located at the antennas
  • A low-loss feedline system for both the transmit and receive sides of the system
  • Use of both the MAP65 and standard versions for WSJT-X for digital operations
  • Use of Linrad as a front-end to the receive side of our system
  • Our existing Icom IC-9100 Transceiver and M2 1K2 2m Power Amplifier for transmitting


WA1NZP Antenna System (4 M2 XP32 X-Polarity Antenna Array)

WA1NZP Antenna System (4 M2 Antennas XP32 X-Polarity Antenna Array)

It takes some fairly large antennas to create an 80th percentile EME station. We are planning a setup similar to Bob, WA1NZP’s system shown above. We are going to put up a 26′ Rohn 55G tower for our EME antenna system. We will be using four M2 Antenna System XP28 Antennas mounted on an H-frame to create a 15′ x 15′ square array.

The combined gain of the system will be approximately 23 dBi with a 3 dB beamwidth of 12.5°. The XP28 antennas are designed for stacking and have good Gain/Temperature (G/T) characteristics. G/T is a measure of the gain and noise performance of an antenna system. See VE7BQH’s tables for some interesting data on G/T for many commercially available EME and VHF+ antennas.

The antenna system will have separate feeds for the antenna array’s Horizontal (H) and Vertical (V) planes. The Horizontal elements will be oriented parallel to the ground to maximize ground gain when the H plane is used for transmitting (and receive). A pair of 4-port power combiners will be used to combine the H and V polarities of the four antennas into a pair of H and V feedline connections.

Plans call for a combination of the M2 Orion 2800G2 and MT3000A rotators to be used along with a Green Heron RT-21 Az/El Rotator Controller to provide computer-controlled tracking of the moon. A 22′ section of 3″ Chrome Molly mast material will allow the azimuth rotator to be located near the base of the tower where it can be easily serviced.

Tower Mounted Preamps and Polarity Switching

MAP65 Switching and Preamp Housing

MAP65 Switching and Preamp Housing

M2 Antenna Systems will be supplying a MAP65 Switching and Preamp System that will mount on the tower near the antennas. The MAP65 Housing provides switching and separate receive preamplifiers and feedlines for the H and V polarities of the antennas. Separate H and V receive coax connections bring the Horizontal and Vertical elements of the antennas back to the shack. A third coax connection is provided for Transmit. The transmit feedline can be routed to either the H or the V antenna polarity to help minimize Faraday Rotation related fading at the other end of the contact.

S2 Sequencer

S2 Sequencer

An M2 Antennas S2 Sequencer will provide Tx/Rx sequencing and H/V transmit polarity selection via the MAP65 Switching and Preamp System on the tower. The sequencer is essential to provide safe changeovers between receive and transmit and to protect the preamplifiers and the power amplifier during high power operation.

Feedline plans call for a run of 7/8″ Hardline Coax for transmit and a pair of LMR-400uF Coax cables for the H and V receive polarities.

MAP65 Capable Receive Chain

LinRF IQ+ Block Diagram

LinRF IQ+ Block Diagram

The signals returning from the moon in an EME system are very, very weak. Because of this, Noise and Dynamic Range performance are critical factors in an EME receive system. In addition, we will need a pair of high-performance, phase-coherent receivers to enable Adaptive Polarization via MAP65.

LinkRF IQ+ Dual Polarity Receive System

LinkRF IQ+ Dual Polarity Receive System

We are planning to use a LinkRF IQ+ Dual Channel Receive Converter in our EME system. The Link RF IQ+ features excellent noise and dynamic range performance and its phase-coherent design will support adaptive polarity via MAP65. The IQ+ separately converts both the H and V polarities of the antennas into two separate pairs of I/Q streams.

UADC4 High-Performance A/D Converter

UADC4 High-Performance 4-Channel A/D Converter

The four channels (two I/Q streams) from the LinkRF IQ+ must be digitized and fed to a Windows PC for decoding. The conventional way to do this is with a 4-channel, 24-bit soundcard. The available computer soundcards add a good bit of noise and therefore limit the overall dynamic range of an EME system. Alex, HB9DRI at LinkRF has come up with the UADC4 – a high-performance 4-channel ADC that is specially designed for software-defined radio. The UADC4 design is based on CERO- IF conversion and is optimized for EME use. The UADC4 should add about 10 – 15 dB of dynamic range improvement over a typical 24-bit PC Soundcard. Alex is currently taking pre-orders for the next run for UADC4 devices. You can contact him at info@linkrf.ch for more information.


JT65 Software Block Diagram

JT65B Software Block Diagram

Our plans for JT65 software and related components for our EME station are shown above. We are planning on running a combination of Linrad and WSJT software on the same Windows PC to handle JT65B QSOs. There are two configurations that are applicable to our plans:

We are also planning to develop a simple windows application that will read the Moon Tracking data that is generated by WSJT MAP65 and WSJT-X and use it to control the rotator system associated with our EME antennas. More on this to come in a future article.

Transmit System

2m Amplifier And Sequencers

2m Amplifier and Sequencers

A combination of our existing Icom IC-9100 Transceiver and our 2M-1K2 Amplifier will be used for the Transmit side of our system. The 2M-1K2 can generate about 900W when transmitting in JT65B mode.

Well, that about covers it as far as our 2m EME goals and station design go. The plan is to break ground for the new EME tower later this week. 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 EME Station 2.0 project:

Fred, AB1OC

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

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

Amatuer Radio Video How-To – Putting Up A Tower

July 2019 Tech Night – Putting Up A Tower

We recently did a how-to presentation on Putting Up A Tower at a Nashua Area Radio Society Tech Night. The video from this presentation can be viewed above.

Putting Up A Tower Video – Topics Covered

We covered a variety of information related to planning, building and integrating Guyed and House-Bracketed towers. You can view the accompanying presentation materials here.

The Nashua Area Radio Society produces similar how-to training materials on almost a monthly basis and we make these materials available to our Members an Internet Subscribers (folks that live too far from our location to be regular members) for a small cost which supports our new Ham development programs and covers the production and storage costs associated with the video material. Here’s a list of the training topics that we’ve produced to date:

2019 Tech Nights

  • Fox Hunting: Radio Direction Finding for Beginners including a Tape Measure Yagi Build by Jamey Finchum, AC1DC
  • Surface Mount Technology by Hamilton Stewart, K1HMS
  • RF Design with Smith Charts, Building a First HF Station, and Begining with CW – Hamilton Stewart, K1HMS; Anthony Rizzolo, KC1DXL; and Jerry Doty, K1OKD
  • All About Field Day 2019 by our Field Day Planning Team
  • Putting up a Tower by Fred Kemmerer, AB1OC

2018 Tech Nights

  • Operating Your Station Remotely by Fred Kemmerer, AB1OC
  • Transceiver Frequency Measurement and Calibration by George Allison, K1IG.
  • DMR Radios and Programming by Bill Barber, NE1B
  • WSJT-X: FT8, WSPR, MSK144 and More by Fred Kemmerer, AB1OC
  • Getting Started with Raspberry Pi Computers by Anita Kemmerer, AB1QB, Jamey Finchum, AC1DC,  Brian McCaffrey, W1BP, Fred Kemmerer, AB1OC, and Craig Bailey, N1SFT
  • All About Field Day 2018 by our Field Day Planning Team
  • Portable Operating Gear – demonstrations by Nashua Area Radio Society Members
  • K1EL Kits by Steve Elliott, K1EL
  • Antenna Modeling I by Scott Andersen, NE1RD.
  • Building and Operating a Mobile HF Station by Fred Kemmerer, AB1OC

2017 Tech Nights

  • High-Altitude Balloons: Amateur Radio at the Edge of Space and was presented by our HAB Team.
  • Getting On The Air 2.0 by Fred Kemmerer, AB1OC, and B. Scott Andersen, NE1RD
  • All About n1fd.org – Getting the most from our Website by Fred Kemmerer, AB1OC.
  • Digital Modes: RTTY, PSK, and WSJT-X by Mike Struzik AB1YKAnita Kemmerer AB1QB, and Fred Kemmerer, AB1OC
  • Bonding and Grounding by Jeff Millar, WA1HCO and Fred Kemmerer, AB1OC.
  • All About Field Day 2017  by Dave Merchant, K1DLM, and our Field Day Planning Team.
  • Building and Operating a Satellite Ground Station by Burns Fisher, W2BFJ and Fred Kemmerer, AB1OC.
  • DXing and QSLing by Anita Kemmerer, AB1QB; Bill Barber, NE1B; Fred Kemmerer, AB1OC; and Dick Powell, WK1J.
  • Weak Signal VHF and UHF Stations by Jeff Millar, WA1HCO and Bill Barber, NE1B.
  • Getting the Most from your HF Transceiver and More by Fred Kemmerer, AB1OC and Dave Michaels, N1RF.

2016 Tech Nights

  • Popular Loggers – Ham Radio Deluxe and DXLab Suite by Dave Merchant, K1DLM and Fred Kemmerer, AB1OC.
  • Low-Band Antennas by Dennis Marandos, K1LGQ; Hamilton Stewart, K1HMS; Brian McCaffrey, W1BP; and Fred Kemmerer, AB1OC.
  • RF Simulation and Matching by Jeff Millar, WA1HCO
  • Directional Antennas by Fred Kemmerer, AB1OC; Dave Michaels, N1RF; Brian Smigielski, AB1ZO; and Greg Fuller, W1TEN
  • All About Field Day 2016  by our Field Day Planning Team.
  • Surface Mount Soldering and Desoldering, a Hands-On Presentation by Jeff Millar, WA1HCO
  • Building Your First Station and Getting On The Air by Fred Kemmerer, AB1OC, and Dave Michaels N1RF
  • Software Defined Radios by Fred Kemmerer, AB1OC and Skip Youngberg, K1NKR
  • Advanced Repeaters (DMR, EchoLink, DMR, and D-STAR) by Anita Kemmerer; AB1QB, Fred Kemmerer, AB1OC; and Bill Barber, NE1B
  • Antenna Modeling with EZNEC by Fred Kemmerer, AB1OC

You can gain on-going access to the full library of Amateur Radio Training and How-To materials by supporting our work to bring new people and young people into the Amateur Radio Service as a Nashua Area Radio Society Internet Subscriber. You can learn more about how to become an Internet Subscriber here.

Fred, AB1OC

Field Day Satellites, VHF+ and Fox Hunting

We will have lots of great activities for folks who are interested in operating on the VHF and above bands at Field Day 2019. Here are some of the activities that we’ll be doing:

  • Satellites Contacts using a Portable Computer Controlled Satellite Stations
  • Weak Signal SSB, CW, and FT8 Contacts on 6m, 2m, and 70cm
  • Fox Hunting using Radio Direction Finding (RDF) to find hidden 2m Radio Transmitters
  • Satellite Station, VHF+ Station, and Fox Hunting Training

Source: Field Day Satellites, VHF, and Fox Hunting – Field Day 2019

The Nashua Area Radio Society always brings something new to each Field Day that we do. In addition to our Computer Controlled Satellite Station, we will be adding a state of the art Weak Signal Antenna System and Station to our Field Day 2019 lineup. Our VHF Station will use a dedicated 40 ft Tower with Tower Mounted Preamps and low-loss feedlines. You can see what is going on at Field Day 2019 on 6m and above via the preceding link.

Fred, AB1OC