First Tower Part 5 – Tower/Antenna System Analysis And Design (HFTA Analysis)

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SteppIR DB36 Array at 105'/65' on 20m

SteppIR DB36 Array at 105’/65′ on 20m

The next step in the design of our new antenna system and the tower was to perform a High-Frequency Terrain Analysis (HFTA) for our specific QTH. An excellent explanation of how to use HFTA and the required SW can be found in the ARRL Antenna Book. HFTA uses coordinates and information about the planned antennas and heights to perform a very thorough analysis and prediction of the likely performance of a Yagi-based antenna system for a specific location and associated terrain. The software also includes files that give the probability that a Contact will occur on a given arrival angle for stations in all major regions of the world to major population centers (these files are called elevation statistics files) and this data is provided across all phases of the sunspot cycle. This allows one to predict how a given antenna system at a specific location will perform under all propagation conditions when a given band is open. The steps required to perform this analysis are as follows:

  1. Download and install the latest versions of the MicroDEM and HFTA programs (the only source I can find for HFTA is the CDROM which comes with the ARRL Antenna Book).
  2. Determine the GPS coordinates of the planned location of the tower/antennas (this can be most easily done with a GPS receiver or Google Maps).
  3. Use the USGS (US Government Survey) website to download a set of Digital Elevation Maps (DEMs) for your location and merge them into a single seamless DEM using MicroDEM (this is the most difficult part)
  4. Use MicroDEM to generate a set of profiles (.pro) files for the tower location. Generally, these are done every 5 degrees for a full 360 degrees around the tower site.
  5. Get the elevation statistics files for 7 regions of the world (US, Europe, Africa, South America, Oceania, Asia, and Japan) for the closest metropolitan area to you (in my case this was Boston, MA USA).
  6. Decide which azimuth angles you want to analyze for each region (we used four angles 15 – 20 degrees apart for each region)
  7. Decide upon the antenna types and heights you want to analyze. We used the following values for our final analysis:
    • 80m – dipole at 105′
    • 40m & 30m – 3 Element Yagis at 105′ and 65′ as an array
    • 20m – 10m – 4 Element Yagis at 105′ and 65′ as an array
    • 6m – 6 Element Yagis at 105′ and 65′ as individual antennas
    • In the case of array combinations, we analyzed both antennas in-phase (BIP) and both antennas out-of-phase (BOP)

The HFTA .pdf file explains all of these steps in detail. With this information and files in hand, you are ready to perform the HFTA analysis.

Here’s what the merged DEM file for our location looks like.

Merged DEM for our QTH

Merged DEM for our QTH

The circles represent mile distances from our tower site. In this post, we will look at the HFTA analysis for our antenna system for one azimuth angle (65 degrees) from our QTH toward Europe. We merged a total of 6 individual DEMs to create the seamless merged DEM shown in the figure (see the HFTA .pdf file for the details on how to do this).

The first information that HFTA can produce is a graph of the terrain profile in a selected direction. Here’s what this data looks like for our site towards Europe at 65 degrees.

Terrain Profile Towards Europe

Terrain Profile Towards Europe

The two diamonds on the graph show the elevation of the two DB36 Yagis at 105′ and 65′. The terrain is conducive to good propagation in this direction from our site and our experience with our existing antennas supports this conclusion.

Next, let’s look at the performance that HFTA predicts towards Europe for our planned system on 40m.

DB36 Array at 105'/65' on 40m

DB36 Array at 105’/65′ on 40m

There is a lot of information here so let’s step through how to read the chart. In the upper left, you can see the parameters of the HFTA run:

  • Frequency analyzed was 7.2 MHz (40m)
  • Two array combinations were run with a pair of 3 Element Yagis at 105′ and 65′
    • Both antennas in-phase (the Blue trace) and
    • Both antennas out-of-phase (the Red trace). Note the ‘*’ on the antenna at 65′ which indicates it is modeled as 180 degrees out of phase with the antenna at 105′).
  • The elevation statistics used for the run were for Boston towards Europe (the W1-MA-EU.PRN file).

The gain of each antenna at a given Takeoff (T/O) Angle is shown on the left vertical scale. You can see that a peak gain of about 15 dBi occurs with the in-phase combination at an arrival angle of about 20 degrees. Note that this tracks well with the EZNEC analysis over flat ground in the previous post. The increase in gain here is partially due to the enhanced “ground gain” developed since the actual terrain slopes away from the antenna.

The Purple bars at the bottom of the graph show the probability that a station in Europe will arrive at a given T/O angle. You can read the actual probability for a given T/O angle bar on the right vertical scale as a percentage. Note that this part of the data is based upon predictions and actual measurements over a range of sunspot levels across the entire 13-year sunspot cycle. Note that this does not mean that the band will always be open; rather the bars indicate the probability that a station from Europe will arrive on a given angle if the band is open.

Note that the single most important arrival angle is at 1 degree which accounts for almost 8% of all contacts. This is common and speaks to the importance of engineering an antenna system that performs well at low T/O angles. Also, note that our planned system does a reasonably good job of covering all T/O angles from Europe in this direction. Thus, we can expect to work station on 40m from Europe any time that the 40m band is open.

Now let’s look at the performance of our planned system on 20m.

DB36 Array at 105'/65' on 20m

DB36 Array at 105’/65′ on 20m

First, note how the in-phase configuration of the array (Blue trace) does not do a good job of covering some important takeoff angles above 20 degrees. This is indicated by the “dip” or “null” in the Blue trace. Fortunately, the Stack Match system we are using with the array can also operate the two antennas 180 degrees out of phase (BOP). The Red trace shows how the array will perform in BOP mode. As you can see, the BOP configuration fills in the null nicely and the resulting BIP/BOP combination has 10 dBi or more of gain at almost all T/O angles (except for 1 degree where we have 7 dBi). The ability to change the pattern (in this case to higher T/O angles) is the main reason for selecting a Stack Match system that supports BIP and BOP operation.

Finally, let’s see what happens on 6m. The first thing to note is that it is practically impossible to build a Stack Match system which can create a phased array on all of the HF bands and 6m. The ability to match the antennas in this configuration over such a wide frequency range is not achievable at high power with available components. As a result, most HF Stack Match systems (including the one we are using) will create an array of antennas on 160m – 10m and will allow either antenna in the stack to be used individually on 6m. This is the mode of operation that we will look at on 6m.

Individual DB36 Antennas at 105'/65' on 6m

Individual DB36 Antennas at 105’/65′ on 6m

As you can see, the combination of the individual upper and lower DB36 antennas do a pretty good job of covering most T/O angles from Europe on 6m. Except for 15 – 17 degrees, we have 10 dBi or more of gain from one of the two antennas. This leaves only about 5% of the angles covered with 5-10 dBi of gain. The net of all of this is that we should do a good job of working stations in Europe on 6m when the band is open.

We did this analysis for all 7 regions, on all HF bands (including the WARC bands) and 6m, trying different antenna heights and separations. After all of this analysis, we settled on placing the two DB36 antennas at 105′ and 65′. This combination along with the BIP/BOP and individual antenna selection capabilities allow us to cover almost all T/O angles of importance to major parts of the world throughout the sunspot cycle. In almost all cases, we can work nearly all stations on a given band if it’s open. Obviously, all of this analysis consumed a considerable amount of time but I feel the work was well worth it. The resulting “book” of  EZNEC and HFTA information has been printed and should make a useful operating aide for our Station once our new antenna system is completed and operational.

Now that we know the target heights of our tower and antennas, we can complete the mechanical layout and wind loading analysis for our tower. We will cover these steps in our next post.

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

First Tower Part 4 – Tower/Antenna System Analysis And Design (Planning And EZNEC)

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Antenna System Design and Layout Plan

Antenna System Design – Layout Plan

As one can imagine, there are many variables and design choices when building an antenna and tower system. We are practically limited to a single tower at our QTH and our desire to build one system that covers many bands and applications made the engineering aspect of the project a challenge. We also wanted to ensure that the system worked out well mechanically and is safe and reliable. To this end, we invested considerable time in the design and analysis of our new system before building it. The major steps in the engineering phase included:

  1. Determine our goals for the end result
  2. Comparison and selection of beam antennas
  3. Measure the height of closely surrounding trees and perform a “Balloon Test” to get an idea of how visible various tower heights might be in our neighborhood.
  4. Perform an EZNEC Analysis of the beam antennas to determine parameters such as antenna heights and approximate system performance
  5. Perform a High-Frequency Terrain Analysis (HFTA) to more accurately determine the performance of the system over a variety of propagation conditions in our location and to confirm the selected antenna heights
  6. Do a mechanical analysis of the tower system to determine guy wire placement requirements to allow clearance for the rotating antenna mid-tower
  7. Do a wind loading analysis to ensure that the tower is not overloaded
  8. Model interactions between the various antennas at our QTH to ensure different elements of our antenna farm do not significantly degrade each other’s performance
  9. Put all of the pieces together to determine the final specifications for the tower and assemble the support specs and materials for the construction of the system

As you can see, there is quite a bit of information to share and we will cover all of this in a series of posts. This post will cover the first four steps in the process. We will also cover the wire antenna systems for 80m and 160m in a separate series of posts.

The ARRL Antenna Book is an excellent source of the various techniques and software used as part of our design process. I highly recommend that anyone considering an antenna and tower system project like ours spend some time reading the relevant chapters of this book before undertaking the design process.

The first step in a project like this is to determine what you want to accomplish with the end result. Here is a list of our goals:

  • Work DX into all regions of the world on all HF bands 160m – 6m including the WARC bands
  • Be competitive enough in HF contests to have fun
  • Support the legal limit of power and have good receive performance on the target bands
  • Allow for both of us to share the available antennas and operate at the same time. This includes having at least two directions HF beams available for us to share.
  • Allow for future expansion into weak signal VHF/UHF work, possibly including satellite and/or EME operations

As one can imagine, this is quite a wide range of goals it was pretty difficult to achieve all of this with a single-tower system. The first problem was selecting HF beam antennas. After much research, we tentatively settled on a pair of SteppIR DB36 HF Beams. We chose these beams for the following reasons:

  • A single antenna covers all bands 40m – 6m with an option for a rotating dipole on 80m with good performance
  • Since the length of the elements adjust to make the antenna resonant on a single frequency, the antenna produces superior gain and F/B ration performance to other multi-band antennas
  • The antenna behaves much like a mono-band Yagi which supports our desire to operate two transmitters at the same time on different bands.
  • We have been pleased with the performance and reliability of the SteppIR Vertical antenna that we already own

The SteppIR DB36 provides 3 elements on 40m and 30m, 4 elements on 20m – 10m, and 6 elements on 6m. It also has the option to include a rotatable dipole on 80m. The 80m dipole option uses a wire and a loading coil that runs parallel to the boom and uses the end elements to complete the dipole and end load it. The resulting performance is about 0.8 dB less than a full-size 80m dipole. We decided to use two DB36s which allows each of us to use one when operating multi-op. This decision also allowed us to use them together in an array which added additional gain and enabled much cleaner antenna patterns across the wide range of Bands that we are covering with the system (more on this later). Finally, we elected to equip the top DB36 with the 80m dipole option.

The next step was to measure the height of the trees surrounding our backyard. We did this with the goal of getting the tower high enough to get future UHF antennas above the top of the trees. This can be done in a variety of ways. We used a device called a Clinometer and a long tape measure. We found that the trees that would surround the tower ranged in height from about 85′ – 95′. Based upon this, we settled on a tower height of 100′. We wanted to be respectful to our neighbors and limit the visibility of the final installation. To this end, we decided to do a “Balloon Test” to see how visible the final result might be in our neighborhood.

Ballon test to determine tower height.

Balloon Test

This is done by filling a large balloon with Helium and raising it on a string marked every 10′ on a calm day. After some experimentation with various heights, we settled upon a 100′ tower with a 15′ mast on top. At this height, the mast will be about 10′ above the tallest trees that surround our back yard. Only our closest neighbors will be able to see the system when it’s up yet this height will allow future UHF beams to clear the treetops (the angle used to take the picture above makes the balloon look much higher than it is). This test should be done when there are no leaves on the trees as this is the time of year when the system is most visible. The next step was to speak with our nearest neighbors to confirm that they were ‘OK’ with our plans. Fortunately, they were.

The next step was to build models of the DB36s in an antenna analysis program called EZNEC. We did this using the actual dimensions of the boom and element placements/lengths from SteppIR’s DB36 manual and we approximated the curved elements as if they were straight. This is a good model for this antenna on 20m and up and should also be pretty accurate on 40m. All of our Modeling was done using “Poor” ground conditions (what we have here in southern New Hampshire). We experimented with the EZNEC models at various heights and tentatively settled on placing the top antenna on the mast at 105′ and the middle antenna on a rotating ring at 65′. The final choice of spacing is critical for the system to perform well across the wide range of Bands that we plan to operate on. Also, the 105′ height is quite high for a single antenna on 20m and above. To understand our selections, let’s look at some of the EZNEC results.

Single DB36 at 105 ft on 40m

Single DB36 at 105 ft on 40m

As you can see, the upper DB36 provides good gain (12.25 dBi) and a reasonably low Takeoff Angle (T/O) of 18 deg. at the 105′ level. The pattern is not great with a large secondary lobe with a T/O angle of about 60 deg. Now, look at what happens when we add the second DB36 antenna at 65′ configured as an in-phase array.

DB36 Array at 105+65 ft on 40m

DB36 Array at 105+65 ft on 40m

Note how the array improves the overall pattern of the system on 40m. We see a slight increase in overall gain (approximately 1 dB) but the high angle energy is now directed in the upper part of the main lobe which makes this power much more useful for medium-range DX work. Also, note the improvement in the Front/Sidelobe performance indicating the pattern of the system has become “tighter” and more directional in the azimuth plane. All of these differences are worthwhile improvements. As we’ll see later, the Stack Matching system used to create the array will allow us to operate the antennas together both in-phase (BIP) as an array or separately as well as both out-of-phase (BOP). This creates a lot of flexibility in the resulting antenna patterns and enables coverage of almost all arrival angles.

Now let’s look at the EZNEC analysis for 20m. First, we have the pattern for a single DB36 at 105′ on 20m.

Single DB36 at 105 ft on 20m

Single DB36 at 105 ft on 20m

As you can see, we have an excellent T/O angle of only 9 deg. but the antenna pattern is rather badly split into three lobes. Having the energy spread out over a wide range of T/O angles is not necessarily bad but the nulls between the lobes mean that the stations which at these angles will not be able to be worked at all or will be very weak. Now let’s see what happens when we operate the DB36s as a BIP array at 105’/65′.

DB36 Array at 105/65 ft on 20m

DB36 Array at 105/65 ft on 20m

As you can see, array operation improves the pattern of the system on 20m considerably. We also have almost 2 dB of additional gain which will allow us to hear a new layer of stations. The remaining second lobe is down almost 10 dB which indicates that we a placing most of the available power in the main lobe. We will be able to solve the problem of stations arriving at higher angles with BOP operation of the array as you will see in our next post. We also see improved Front/Sidelobe performance indicating a tighter pattern.

Our next post will cover the HFTA analysis to evaluate the system performance at our actual QTH to all areas of the world and the overall phases of the sunspot cycle. Stay tuned!

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

First Tower Part 3 – More Excavation For Feedline Conduits

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We are planning a pretty extensive feedline and control system for our new tower. The plan currently includes:

  • Two 7/8′ hard lines to feed the SteppIR DB36 array
  • One 1/2″ hardline to feed 80m Delta Loop and 160 Invert-L antennas on the tower
  • Two 1 5/8″ hard lines to feed future UHF antennas
  • A total of 6 control cables for the two SteppIR Beams, two rotators for the Beams, Stack Antenna Phasing System and Remote Antenna Switch
  • Capacity for 6 additional control cables for future use

We also need a 120 VAC outdoor outlet at the base of the tower to provide power for the ring rotator.

The accommodate all of this, we are placing several plastic conduit pipes in a trench from our shack entry point to the tower. The conduits include:

  • One 4″ run for the three new hardline feeders
  • One 6″ run for the future UHF hard lines
  • Two 2″ runs for control cables
  • One 3″ run extending beyond the tower to the back of our lot for possible future use with additional antennas in this location
  • One 1 1/2″ conduit for the 120 VAC cable to the tower

As you can imagine, this requires quite a trench! This part of the construction is compounded by the existence of a sprinkler system and train pipes for the rain spouting as well as the radial field all of which are already in place in the area where the conduits must run. This is yet another job for Brian Veillette (Nashyei@aol.com), our excavation contractor on the project. As you can see from the pictures below, Brain has done a very careful job of creating the trench to minimize the damage to our lawn.

Conduit Trench Run

Conduit Trench

The conduits are laid in a bed of sand and then covered completely with another layer of sand to ensure that the pipes are not damaged by freezing and thawing of the ground. We also constructed two moisture drains under the conduits at the ends and place small holes in the pipes at the bottom to allow the water that will ultimately accumulate in the pipes to drain into the ground. Also, note the drainage pipes installed on the rain spoutings to carry rainwater from the room away from the conduit area and the shack in the basement. These are important steps to ensure that the feedline in the conduits stay dry and perform well for an extended period of time. It’s also important to create a gradual upslope at the ends of the conduits which will contain hardline feeders as these cables are stiff and cannot be bent sharply as the come out of the ground. This is accomplished by using a pair of 22.5-degree elbows on each end of the conduits to bring them out of the ground.

Conduits at Shack entry

Conduits at Shack

As you can see, we still have some work to do to complete the conduit work. We expect to finish this part of the project early next week. Once this is done and the remaining parts arrive for the tower, we will be ready to put it up!

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

First Tower Part 2 – Tower/Antenna System Design Details And Equipment Ordering

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Finished Tower Base

Finished Tower Base

Now that we have backfilled the base and guy anchors for our tower, we are ready to have the equalizer plates and guy wires attached. We are planning to use two sets of star guys on the tower – one set of 6 guys at 50’ and a second set at 95’ (5′ down from the top). Star guys use special brackets where the guys attach to the tower to connect two guy wires on each tower leg for a total of 6 at each level instead of the usual three. This prevents the tower from torque-ing when the rotators start and stop moving the large beams (we are using a pair of SteppIR DB36’s – full-size 40m beams weighing about 165 lbs. each).

We also ordered a number of parts for the final tower over the last couple of days. Here is a rundown of the components and some links in case you are interested in what these components are:

The SteppIR antennas cover all bands 40m – 6m including the WARC bands. One of the DB36’s (the top one) will have an 80m dipole option that uses a wire running parallel to the beam (36’) plus the end elements of the antenna and a pair of loading coils to create a rotatable 80m dipole. This should be reasonably effective at the 105’ level where this antenna will be mounted. The ring rotator allows the lower beam to rotate around the tower and the Green Heron Controllers synchronize the upper Beam’s rotator with the lower ring to move both antennas in the array together. The Green Heron controllers also come with software that allows them to be operated over the internet which will allow me to use the station and move the beams while I am traveling via a PC and the Internet. The DX Engineering Broadband Matching system allows the two Beams to operate as an array increasing the overall gain of the system and improving the radiation patterns of the antennas. The Matching System and the two associated antennas can be used three ways – as an array in-phase, as an array out-of-phase and individually. This allows us to cover a much larger set of takeoff angles to optimize the performance of the system based upon the propagation conditions at any given time.

We chose Phillystran Guy material which is made of Kevlar and is non-conducting. This ensures that the guy wires will not be resonant on the HAM bands and upset the tune or interact with the antennas on the tower. The Phillystran will transition to a normal steel guy wire near the ground for safety reasons. Rohn 55G tower is strong stuff and we chose it to maximize the antenna and wind loading capacity of the system. Check out the 55G Brochure via this link for details on the 55G tower kit and related hardware. Finally, the 21’ H.D. mast will allow us to add additional antennas for 2M and 70 cm above the top SteppIR beam in the future. The first 5’ of the mast goes inside the tower which leaves 16’ of the mast to mount antennas on. This allows us to put an antenna as high as 115’. The mast is also climbable which should make for some exciting times (and pictures) sometime in the future.

We are also planning to add an 80m Delta Loop antenna and a 160m Inverted-L antenna to the tower. These antennas will be selectable at the tower via a DX Engineering Remote Antenna switch. The tower is located right next to our current SteppIR vertical antenna which has a large radial field under it (forty-eight 85′ radials). We need to move the Vertical antenna to a new location due to the tower but we can re-use the existing radial field to improve the performance of the 160m and 80m antennas on the tower. We plan to add a few 170′ radials to the field to improve its performance on 160m.

We are in the process of completing an HFTA and EZNEC modeling analysis of the complete antenna system to finalize the height of the two beams and the design of the 160m and 80m antennas. Look for a future post on this work. Right now it looks like the two beams will likely perform best when installed at 102′ and 65′.

You can read more about our tower project via the articles which follow:

– Fred, AB1OC

First Tower Part 1 – Ground Broken For New Tower!

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We have finally broken the ground and started the construction of a new Amateur Radio tower and antenna system for our station. The plan for our new antenna system is as follows:

  • 100’ Rohn 55G star guyed tower
  • Two SteppIR DB36 beams 40m-6m in an array
  • The top antenna on an M2 Azimuth Rotator, the middle antenna on a K0XG ring rotator
  • 160m Inverted-L installed on side of the tower
  • 80m Loop installed at the apex of the tower
  • Hardline feeders (3) for the two SteppIR beams and the 160m and 80m wire antennas

If all works as planned, we should have a great signal on all bands 80m-6m. We are also making provisions for adding 2M and 70cm long beam antennas or perhaps an az/el UHF array on the top of the tower at a later date.

We are working with a local tower contractor, Matt Strelow at XX Towers to build our tower and antenna system. Matt has a great deal of experience with Amateur Radio Antenna Systems like ours and he has been a great help in planning our project and getting it going. We are also working with a local excavation contractor, Brian Veillette (Nashyei@aol.com) to handle all of the excavation work for the tower as well as to install the feedline conduits to bring feedlines from the tower to the shack entry.

We were fortunate to purchase a nearly new Rohn 55G tower kit locally. This not only saved on the cost of the tower but also a significant expense for shipping. The kit is an 80′ Rohn 55G tower and we are adding two additional sections to it to create a 100′ tower.

Amatuer Radio Tower - 80' Rohn Tower Kit

Rohn 55G Tower Kit

The first step was to obtain a building permit and layout the location of the tower base and three guy anchor blocks. Matt from XX Towers was able to find a good spot on our lot that places the tower about 100′ from the entry point to our shack and located the guy anchors about 100′ from it in the woods on the edge of our property. Next, Brian Veillette used his backhoe to dig 4′ deep holes for the base pad of the tower and the three guy anchors. Then holes were fitted with the proper rebar cages and forms.

Hold and rebhar reinforcing for amateur radio tower base slab.

Base Foundation

Amateur Radio Tower - Reinforcing rod and structure for guy anchor

Guy Anchor Ready for Cement

After completing our first building inspection. We ordered 5 cubic yards of 4,000 lb. strength concrete from a local Redi-Mix company. The cement mixer showed up the next morning.

Redi-mix Cement Mixer

Cement Mixer

The weight of the cement truck would have likely damaged our driveway and it could not reach the location where the tower is located anyway so Brian Veillette used his front-end loader to move the cement one bucket at a time from the street into the forms.

Amateur Radio Tower - Pouring Cement for our tower base..

Pouring Cement for the Tower Base

The guy anchor blocks were a “free pour” directly into the holes.

Guy Anchor Block

Guy Anchor Block

We finished the tower base and allowed the cement to set up for two days before removing the forms. We used a brick to smooth the cement on the top and sides of the base to create a nice finish. The threaded rod on the base slab is used to hold the tower base to the slab. This also allows the tower to be removed from the base in the future if necessary.

Finished Amatuer Radio Tower Base

Finished Tower Base

It’s important to keep the cement moist with water for about a week until in cures some to ensure that the final structures reach their full strength. We accomplished this by pouring a bucket of water on the cement structures once a day and keeping them covered with a plastic tarp to keep the cement damp while it cured.

We have backfilled the guy anchors and they present a low profile in the woods at the edge of our property.

Finished Guy Anchor after Backfilling

Finished Guy Anchor

We are both working different parts of our tower project, Anita is project managing the entire project, ordering much of the equipment, and has done a great deal to coordinate all of our sub-contractors working with us. Fred is doing the overall planning and engineering and working with the contractors to build the system. We are both doing work to clear brush, clean up the landscaping around the tower and the shack, and assisting the contractors in their work.

Anita, AB1QB is shown working on our tower project.

AB1QB Working on the Tower Project

The next step in our tower project is to install conduits in our yard to run feedlines and control lines from the shack to the tower. You can read more about our tower project via the articles which follow:

– Fred, AB1OC

A Tour Of Our Shack

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Our New Shack

I wanted to share a little more about our new shack, which was recently completed. Anita and I each have our own operating positions, which are SO2R capable. Anita’s setup consists of a Yaesu FTdx5000 and has provisions to add a second radio in the future. Fred’s position uses an Icom IC-7800 and an Icom IC-9100. Some of the key specifications and capabilities of our shack include:

  • A manual antenna switching matrix that allows us to connect any one of 6 antennas to our radios
  • W3QN bandpass filters systems for each radio to allow simultaneous operation of multiple transmitters at the same time on different bands
  • microHAM MK2R+ and SignalLink USB sound cards to enable digital mode operation
  • Dedicated displays and keyboards for the FTdx5000 ahttps://www.n1fd.org/2017/04/23/member-spotlight-ab1qb/nd IC-7800 radios to enable better use of their built-in Pan Adapters
  • Icom and Yaesu desk microphones and Heil ProSet headsets with boom microphones
  • Bencher paddle for CW
  • Windows 7 (64-bit) computers with dual monitors for running all manner of HAM software (we mainly use Ham Radio Deluxe at this time – more on software in a future post)
  • An Icom PW-1 Kilowatt Solid State Amplifier

The shack also has 125A of dedicated AC power, 70A of DC power, and its own Heat Pump system for heating and cooling. Our house also has a 20 KW automatic generator system that provides emergency power to the shack.

The following are a few pictures of our shack:

This is Fred's operating position.

AB1OC Position

This is Anita's operating position.

AB1QB Position

Our shack also has a dedicated area for equipment construction and test. It sure is nice to have a place where all of our test equipment, etc. can be left connected and set up for immediate use.

Electronic equipment for equipment construction and test.

Construction Area

Our shack includes areas for storage and an A-V area with a TV and entertainment audio. These are all essential items for a complete HAM-cave.

Storage and display area

Storage Area

TV and Entertainment Audio Equipment

A-V Area

Anita and I were able to use our new shack in its multi-op configuration for the 13 Colonies Special Event on the 4th of July. We were both on the air at the same time as K2K New Hampshire, and this was the first test of our station in a multi-operator configuration. One of us did SSB-phone on one band to avoid audio interference, while the other operated digital modes on a different band. For now, we built a matrix of manual antenna switches, allowing any of our four radios to use any available antennas. In the future, we plan to automate all of this with a microHAM system.

The work to construct our shack took about 8 months and was quite a bit of work. We started with an unfinished area of our basement, and we did the framing, electrical, HVAC, plumbing, drywall, ceiling, floor, and finish work. We had the help of several great contractors along the way. We plan to do a series of posts sometime in the future to explain a little more about what went into the construction of the room and the systems which support it.

[fvplayer id=”3″]

The video playlist above provides a “Virtual Station Tour” of our station.

Are you interested in learning more about our shack design and construction? Here are some links with more information:

– Fred, AB1OC

Welcome To Our Blog!

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Our Shack

We are in the process of building a state of the art multi-operator Amateur Radio Station. We have created this blog to share our plans, experiences and learnings as we go. We hope that this information will be useful to other HAMs and potential HAMs that are thinking about building a station. Anita and Fred, the authors, are recently licensed Amateur Radio Operators and this is our first permanent station project. Our goals for our station are as follows:

  • A station that will operate and perform well on all HF bands and 6m as well as provide access to our local VHF and UHF repeaters
  • Support all modes of operation including SSB Phone, Digital and CW
  • Allow both of us to operate at the same time and also support Single Operator 2 Radio (SO2R) operations
  • Allow us to have fun working DX and contests
  • Be easily expandable for VHF/UHF weak signal work in the future

There are two parts to this project. The first is the construction of a permanent station in a dedicated, finished room in our basement and the second is to build a good antenna farm. As I write this, the station room is complete (see picture above) as is a basic part of the antenna farm. As time permits, we will add details and pictures of these parts of our project as well as the end result. The current work in progress in the construction of a new antenna system based upon a 100′ tower and an array of large yagi antennas as well as some new wire antennas which will be attached to the tower. Most of our early posts will likely focus on this area.

We welcome everyone’s thoughts and comments on our project via this blog. We hope that you enjoy the material that we are sharing here!

– Fred (AB1OC) and Anita (AB1QB)