Mobile HF Installation – Part 3/4 (Screwdriver Antenna Installation)

October 13, 2014 by AB1OC

Icom IC-7000 Mobile HF Radio

We have made some 250+ contacts using the Mobile HF setup in our Ford F-150 Truck. Our initial setup used an Icom IC-7000 Transceiver and HAM Stick Antennas. This combination enabled us to work a lot of DX from our truck (56 DXCC’s worked mobile HF to date). It is surprising how well a properly installed Mobile HF setup works. For more information on our Mobile HF installation project, see our other articles here –

Phase 1 – Install the Icom IC-7000 running barefoot with a simple MFJ HAMStick Antenna (to be replaced with the Scorpion Screwdriver Antenna in Phase 3)
Phase 2 – Properly bond all elements of my truck and deal with any noise issues
Phase 3 – Install the Scorpion Screwdriver Antenna and Controller (this article)
Phase 4 – Install a 500w Amplifier, 160m capability, and operating accessories

Our plan has been to enhance our Mobile HF installation to include a Screwdriver Antenna and a Mobile Amplifier. This article covers the first of these upgrades.

Scorpion SA-680 Screwdriver Antenna

We chose a Scorpion SA-680 Screwdriver Antenna for our project. Scorpion mobile HF antennas are among the best in quality and efficiency. The SA-680 covers all HAM bands from 80m – 10m (160m operation will also be added to this antenna – more on this in a later post). The SA-680 is also a good choice given our plans to add a mobile HF amplifier to our truck (the SA-680 is rated for 1500 Watts SSB PEP). We ordered our antenna with a flat black powder-coated finish to match the color scheme on our truck. Scorpion antennas can accommodate a variety of whips, and we have both 6-foot (supplied with the antenna) and 8.5-foot whips available. We also ordered a 3-foot-long rod with a Cap Hat, and this is the combination that we are currently using. This arrangement features improved efficiency due to the top-loading of the antenna the Cap Hat provides and a reduced height profile, which is perfect for avoiding the low tree branches here in New England, USA. Ron Douglas, NI7J owner of Scorpion Antennas, has been a great help providing lots of good advice to help us to install his SA-680 antenna properly.

Breedlove Folder-Over Antenna Mount

The Scorpion SA-680 Antenna is a beefy unit and weighs about 18 pounds. This antenna requires a strong mounting system for safety and reliable operation. We chose to mount our antenna in the bed of our F-150 Truck using a fold-over mount from Breedlove Antenna Mounts. This mount is made specifically for the Scorpion Antenna and uses a 1/2″ thick aluminum plate with reinforcing bars that mount under the truck bed to ensure that the mount is rigid and does not crack the truck bed due to the load of the antenna. As you can see from the picture above, we cut the plastic bed liner, which protects our truck’s body to allow the base of the antenna to sit on the truck body’s sheet metal. We used star washers between the mount and the bed to ensure that the mount made a good RF connection with the bed of the truck.

Antenna In Folder Down Position

One of the nice features of this mount is its ability to be folded over to 90 or 45 degrees. This is done by loosening two large Allen screws on the mount. The picture above shows the antenna folded over with the Cap Hat/Rod removed. In this position, we can close the roll cover on our truck’s bed to completely cover the antenna. This is great for taking the truck through the car wash or protecting the antenna from the winter weather here in New England.

Scorpion Whip Quick Disconnect

Removal of the Cap Hat/Rod or an attached whip is made easy by Scorpion’s Quick Disconnect. The ones on our antenna are made from stainless steel and allow easy removal of the Cap Hat Rod or a whip.

Control And Feedline Choking

All Screwdriver antennas require control cables to operate a motor that raises and lowers the antenna to change the length of a base loading coil. This is how the antenna is tuned to operate on different bands and frequencies. The motor and associated control leads operate at a high RF potential relative to the vehicle’s ground. This is also a problem for the outside shield on the coax cable feeding the antenna. The RF potential on the control cables and feedlines must be choked, or it will enter the vehicle and cause RFI problems. Proper RF choking is especially important in our installation as we plan on running high power via an amplifier. To ensure proper choking, we built a series of RF chokes for the six control lines from the antenna – one pair for the 2 motor leads, one pair for the 2 pulse count leads that are used to sense the position of the antenna, and one pair for a future shunt coil relay to enable 160m operation. These chokes were built according to the information on K0BG’s excellent Mobile HF website. Each pair of control leads were run through two separate chokes at the base of the antenna (two chokes were used due to the planned high-power operation with an amplifier). Two chokes were also used on the RG-8X feedline. For the initial installation, the supplied shunt coil (copper coil on the left side of the antenna base) was used to match the antenna on 80m and 40m. The coil was adjusted using the procedure on K0BG’s website to match these bands well. Also, note the ground strap (visible to the left of the fold-over base). This connects to one of the button head screws at the base of the antenna and to the ground point on the antenna mount to ensure good ground between the antenna and the truck.

Chokes Inside The F-150

Another set of control cable and feedline chokes were made and installed when the antenna cables and feedline entered the vehicle. The picture above shows some additional detail on how the chokes are made. It is important that the chokes be at the same point on each of the control cables and coax feedline so that any RF induced on the cables does not couple from one cable to another and bypass the chokes.

Additional Bonding And Antenna Mount Grounding

I decided to do some additional work on the bonding of the bed of our truck to the rest of the F-150. This involved installing 4 bonding straps between each corner of the F-150’s bed and the frame. I used the excellent strapping material from Electric Motion for this purpose. This strapping features eyelets installed every 3 inches along with the strapping material. This made the attachment of the strapping to the F-150’s bed and frame easy to do via self-tapping stainless steel screws and star washers. A liberal coating of Ideal NOALOX was used on each of the screws and washers to protect against corrosion. Also, note the convoluted tubing which houses the antenna control leads and feedline running along with the frame. The tubing protects the antenna’s cabling and feedline from the weather and enables secure mounting to the vehicle’s frame.

Screwdriver Antenna Manual Controller

The final step in the installation was to connect the antenna control cables to Scorpion’s antenna control switch and mount the switch on the console with velcro strips. This switch is used to raise or lower the antenna, changing the length of the loading coil to tune the antenna for different bands and frequencies. I also installed crimp-on connectors on the RG-8X feedline and connected them to the radio and the antenna. A quick check of the antenna’s SWR on 20m confirmed that the antenna and feedline were working correctly.

I was able to make contacts on the 17m, 20m, 40m, and 80m bands with the new antenna last evening, and it works great. I am particularly pleased with the antenna’s performance on 80m. I made several contacts on this band out to about 2,000 mi and was receiving signal reports ranging from 58 to 59+20dB. These results are very good considering the short length of the antenna’s Cap Hat/Rod (only 3 feet) and that I was using only 100W.

*** Safe operation of your vehicle requires your full attention on the road. You SHOULD NOT try tuning your antennas or radio while your vehicle is in motion. Safety requires that you perform these actions only when your vehicle is stopped and parked safely. ***

The antenna is easy to tune manually. One simply sets the radio to the desired band/frequency and then adjusts the antenna up/down until the maximum reading on the radio’s S-meter is obtained. This usually gets you to within a “coil turn” of the optimal tune-up. I then key the radio up and adjust the antenna up or down to optimize the tune to the lowest SWR, as indicated on the radio. The antenna’s tuning is not critical on 20m and higher bands. It is fairly sharp (due to the short length) on 40m and 80m, so the final adjustment to minimize the SWR is important on these bands.

It’s great to have the full set of Amateur HF bands in the truck with the new antenna. Performance seems comparable to the Ham stick antennas I was using previously on the 20m and higher bands. I would say that this indicates that the efficiency of the Scorpion SA-680 is significantly higher than the Ham stick antennas because the Ham sticks were mounted dead center on the roof of my truck and about 3-4 ft higher than the Scorpion. While this location performed reasonably well on 20m and higher bands, it was not a very practical mounting location due to height problems and difficulty getting at the base on the antenna to change or remove the Ham sticks. Performance is also much better on the 40m and 80m bands with the new antenna. I would say that the new antenna is also somewhat quieter than the Ham sticks were. This is probably due to a combination of being further away from the engine and cab noise sources plus benefits due to the additional bonding work.

The next stage of our Mobile HF project will be the installation of a mobile amplifier, automatic antenna controller, and 160m band add-ons to the Scorpion antenna. I hope to work with some of our readers on the HF bands from our truck soon!

– Fred (AB1OC)

Mobile Ham Radio – VHF-UHF Upgrade

October 13, 2014 by AB1OC

Mobile Ham Radio - Icom ID-5100 Transceiver

Mobile Ham Radio – Icom ID-5100A Transceiver

We installed a 2m / 70cm mobile ham radio setup in our Ford F-150 Truck about 3 years ago. The original installation used an Icom IC-2820H. We used this setup for access to our local repeaters on 2m and 70cm including the many DSTAR repeaters in our area. Our antenna mounts were showing some wear and I’ve been wanting to upgrade to the new Icom ID-5100A for some time now so I decided to replace the entire setup. The Icom ID-5100A was very easy to install – a virtual drop-in replacement for the Icom IC-2820H. The pedestal mount and bracket that I made for the IC-2820H worked fine for the control head of the ID-5100A.

Icom ID-5100 Main Unit Mount

The ID-5100A’s main unit was mounted on the driver’s side kick panel in the same place as the IC-2820H.

The display on the ID-5100A is much easier to read that the IC-2820H and the features that this radio has to locate nearby repeaters based upon the GPS position of the vehicle are also very nice. All in all, the Icom ID-5100A is a much more user-friendly radio to setup and use.

2m / 70cm Mobile Antenna and Mount

The original antenna and mounts on our truck were getting a little tired so I decided to replace them as well. We choose a Diamond K400C NMO mount and a Diamond SG-7900A 2m / 70 cm whip this time around. The Diamond NMO mount is very sturdy and should stand up well to the winters here in New England (as well as the car wash). The new Diamond whip has a bit more gain that the previous setup and is about the limit in terms of height for our location in New England, USA. It is has 5.0 dBi gain on 2m and 7.6 dBi gain on 70cm.

Antenna SWR on 2m

The new mount and antenna was easy to install in our F-150. A final checkout of the antenna’s SWR showed that the new installation was ready to go.

The new radio/antenna combination is working great and the improved usability and display on the ID-5100A is encouraging us to use our local DSTAR repeaters more frequently. The combination was a very worthwhile upgrade.

– Fred (AB1OC)

LEO Satellite System Part 3 – Final Installation And First Contacts

September 19, 2014 by AB1OC

Eggbeater Antennas And Preamps SystemsOn Tower

Eggbeater Satellite Antennas And Preamp System On Tower

With some help from Matt Strelow, KC1XX of XX Towers, we’ve gotten our LEO Satellite Antennas and Preamp System installed on our tower. We installed the antennas on a sidearm at about 80 ft and installed the preamp system (the upper left gray box) next to the antennas on the tower. The design and construction of our LEO Satellite System was covered in the Part 1 and Part 2 articles here on our blog.

Hardlines At The Tower Base

I choose a 7/8″ Heliax Hardline Coax (Andrews AVA5-50) for the feedlines between the antennas on the tower and the shack. I choose this type of cable to hold our losses end-to-end to about 1.0 dB for the 432 MHz side of the system. Our Icom IC-9100 Transceiver, which we will use for satellite work, provides 75W of output on the 70cm band, resulting in a maximum of about 45W at the antenna – plenty of output power for LEO satellite uplink work. The end-to-end loss on the 144 MHz side is about 0.6 dB resulting in an 85W out the maximum from 100W in. The antennas were connected to the preamps and through to the hardline coax cables using short LMR-400UF coax jumpers, and crimp-on N-type connectors were used throughout the system. The conduits buried under our lawn had plenty of capacity for the two additional hardline cables (the lower pair of large coax cables in the picture above). I also routed the control cables for the preamps through one of our smaller conduits.

Hardline Terminations At Our Shack

The hard lines (cables with orange and purple tape) were terminated with N-connectors, and the shack entry end through grounded PolyPhaser Lightning Protectors.

VHF – UHF Antenna Switching Console

The two sides of the LEO Satellite Antenna and Preamp system were terminated on our VHF – UHF switching console in our shack. The console uses Hofi-Technik Rotary UHF Antenna Switches to allow selection of the LEO Satellite Antennas as well as our M2 Antenna Systems 144 MHz and 432 MHz Yagis and a Diamond X-300NA 2m/70cm ground plane vertical, which we use for repeater work.

Preamp Control Cable Terminatons On Tower

Preamp Control Cable Terminations On Tower

We also terminated the control cable from our Preamp System on Control Line Static Suppressors at the base of our tower.

Preamp Sequencers

The Preamp Control Cable was routed to a pair of M2 Antenna Systems S3 Sequencers (top units in the picture above) to enable proper Tx/Rx sequencing to protect the tower-mounted Preamps from damage during transmit. These units allow the 144 MHz and 432 MHz Preamps to be turned on/off separately, as well as enabling the noise test function on the 144 MHz preamp. With all of the installation work done, I confirmed that the SWR reading on both antennas was in the specification at the input to the IC-9100 Transceiver and that both Preamps work (via an observed increase in noise level) when turned on.

Nova For Windows (FO-29 Satellite Pass)

The final step was to install the Nova For Windows program and download the latest Keplerian Elements for the HAM satellites that are currently operational. Nova For Windows allows me to determine when a given satellite is making a pass that covers both my QTH and the area where I want to try to make contacts. The program can also predict future passes, making planning satellite operating times easier. The picture above shows the footprint of the FO-29 and the ISS during a pass over my location.

Fuji Oscar FO-29 Satellite

On the day and time, I tried to make my first contacts, only satellites with Linear Transponders were making useful passes overhead. I try my first contact through FO-29 (Fuji Oscar 29), a V/U Mode (145 MHz uplink/435 MHz downlink) satellite.

First Satelllite Contact - EA1QS In Spain

First Satellite Contact QSL – Pablo, EA1QS In Spain

With my IC-9100 setup in Satellite/SSB Phone mode to transmit and receive on the proper frequencies and side bands and with the Tx and Rx sides set to track each other (this is one of the useful satellite Features provided by the IC-9100), I began by locating a clear frequency on FO-29’s transponder and transmitting on the uplink while adjusting my Rx offset until I could hear my own transmissions coming back from the bird. Once I found my receive frequency, I began looking for a station to work. As good luck would have it, I found Pablo, EA1QS in Spain, and made my first contact! It took some care to stay on frequency during the brief contact as the Doppler shift associated with the path through FO-29 was changing fairly rapidly.

I also made two contacts with W1AW/9, the ARRL Centennial QSO Party Operation in Illinois, USA. I made these two contacts through two different satellites. The first contact was made through VUSat VO-52, a U/V Mode (435 MHz Uplink/145 MHz Downlink) satellite, and the second one was made using FO-29 again. I was quite fortunate to make the contact through VO-52 as its batteries failed, and the bird went out of service just 12 days after my contact was made.

M2 Antenna Systems 70cm and 2m Yagis On Top Of Our Tower

My early experiences with our new LEO Satellite System have been good. The M2 Antenna Systems Eggbeater Antennas and tower-mounted Preamp System work quite well when the Satellites being worked are 30 degrees or more above the horizon. I can use our weak signal 2m and 70cm yagis (top two antennas shown above) and the associated tower-mounted Preamp Systems (two grey boxes just below the top of the tower) for Satellite passes below 30 degrees. This mode of operation will require computer tracking, which I can do via Nova For Windows or the Ham Radio Deluxe Satellite Software, both of which I already have. I plan to try this combination and provide additional setup and operational results for this configuration sometime in the future.

Its been a very busy summer, and I have not as much time to operate using LEO Satellites as I would like. With WRTC 2014, the ARRL Centennial Convention over, and the 13 Colonies Special Event and W1AW/1 New Hampshire portable operations completed, I hope to have more time to devote to Satellite Operation. It’s a lot of fun to make contacts through satellites, and this mode of operation will give us the chance to learn some new skills.

World Radiosport Team Championship 2014 Experiences

August 27, 2014 by AB1OC

Hollis Site Competitors, Referee And Support Team

Anita (AB1QB), Scott (NE1RD) and I had the opportunity to serve as site managers for the WRTC 2014 competition site in Hollis, NH. Our site was one of 65 sites in New England USA (and the only on in the state of New Hampshire). This gave us a chance to be part of the WRTC 2014 event and to meet some of the competitors, referees and the event organizers. WRTC has been called the “Olympics of Amateur Radio” because it brings together the very best Amateur Radio Contesters in the world to see who is the “best of the best”. Here’s a summary of what WRTC is all about from the WRTC 2014 Website:

“The World Radiosport Team Championship (WRTC) is held every four years and consists of 50+ two-person teams of amateur radio operators from around the world competing in a test of operating skill. Unlike most on-the-air competitions, all stations are required to use identical antennas from the same geographic region, eliminating all variables except operating ability.”

Each competitor must qualify based upon results in selected contests over a period of 3 years. There were a total of 63 teams which participated in the event. It is a tremendous achievement just to qualify for WRTC. Each qualifying competitor selects a second person to make up their team. The competitors at our site were Julio Henriquez, AD4Z and Dan Thompson, W4UH. Our referee was Alex Orlov, RW4WR from Russia. We really enjoyed getting to know Julio, Dan and Alex. The stories that they shared and the information and tips they gave us a relatively inexperienced contesters will stick with us forever.

WRTC 2014 Competition Sites

The WRTC 2014 competition was held on July 12-13, 2014 as part of the IARU HF World Championship contest. A great deal of effort was put into selecting and building 65 competition sites for WRTC to ensure that they were as equal in terms of propagation, antennas and configuration as possible. WRTC provided all of the antennas/feedlines, generator power and a tent for each site and each team of competitors supplied their own radios and supporting station equipment.

WRTC Station Kit In Transit

Preparations for WRTC 2014 have been in progress for several years now including planning sessions, station and site tests, team formation and training. All in all, the event is a tremendous planning and logistical effort. Doug Grant, K1DG was the leader and chief evangelist for WRTC 2014. Doug and his team did a tremendous job in making WRTC 2014 happen.

Our part of the WRTC experience began with the pickup of the station kit for the Hollis, NH site on the Wednesday before the event. The station kit consists of a 40 ft Rohn 25G tower, beam/wire antennas, feedlines, generator, tent and miscellaneous equipment.

TX38 Tri-Band Beam Assembly

Ed, K2TE and our “beam team” were at the Hollis, NH site bright and early on Thursday morning to put up the tower and antennas. The heart of the WRTC 2014 antenna system is the TX38 Tri-Band Beam which was designed for WRTC 2014.

TX38 Yagi Installation On Tower

Here’s a picture of the assembled beam and tower ready to be pulled up and into place at our site.

Tower Going Up!

The picture above shows the tower going up. The Falling Derrick System that was developed for WRTC is quite ingenious and it raises the 40 ft tower and beam antenna with very little effort. Each beam team was specially trained in the use of this system to ensure safe setup and takedown of the tower and antennas at each site.

WRTC 2014 Site In Hollis, NH USA

While Ed and the team took care of the tower and antennas, Scott, Anita and I setup the tent, generator, feedlines and “crew tent” at our site. The picture above shows the completed site ready for our competitors.

WRTC Station Radios And Equipment

Julio, Dan and Alex arrived at our site after the site drawing at WRTC headquarters on Friday and proceeded to setup and test their station. As you can see, they brought quite a sophisticated setup! They used Ten-Tec Orion II radios, a microHAM band decoder and antenna switching system and PCs running the N1MM Logger to create a modern, state of the art multi-two contesting station at our site. WRTC competitors used a variety of different radios to compete in the event. You can find a summary of the radios and software used by the competitors here. The Elecraft K3 was the most popular transceiver and a combination of the Wintest and N1MM loggers were used most of the competitors.

WRTC Monitoring System

The WRTC 2014 organizers did some custom design work to facilitate the event. Shown above is the WRTC monitoring system. This system is used by the referee to monitor the power levels of each operator’s radio to ensure that the 100W WRTC power limit is not exceeded. The referees can also monitor the audio from each operator simultaneously and a recording of these audio streams for the entire contest period is also made. All of this is done in the interest of ensuring a fair contest and for judging purposes as needed when the event is complete. A device also monitors the logging streams from the competitors computers to create a live, real-time scoreboard on the web. The scoreboard uses an innovative data collection method developed by Dave Pascoe, KM3T and Bob Raymond, WA1Z to “sniff” the logging information being exchanged by the competitors computers. The data extracted in this way is fed via cellphone data connections to the WRTC headquarters to update the teams scores on the web in real-time during the contest.

The Big Moment – Our Station’s Callsign

On Saturday, just before the competition began, Alex our referee opened the sealed envelope which contained our site’s callsign which was W1T. As with all things about the event, the callsigns were not disclosed to the operators until just before the contest began to ensure that none of the operators specific callsigns were known to others.

Julio (AD4Z) Operating

Once the contest began, our team was all business. Julio is shown above operating CW. He is an amazing operator and can easily operate at 40+ WPM speeds!

Our site was one of the public access sites for the event and we had quite a few visitors from the press and local HAMs who were interested in seeing what WRTC 2014 was about. The event also received quite a bit of media coverage, some of which can be viewed here.

2014 WRTC Medal Winners

An award ceremony was held at WRTC HQ the following Monday to announce and recognize the winners:

Medal winners

Gold K1A 7,184,844 points

Daniel Craig, N6MJ – United States
Chris Hurlbut, KL9A – United States

Silver W1L 6,816,144 points

Rastislav Hrnko, OM3BH – Slovakia
Jozef Lang, OM3GI – Slovakia

Bronze W1P 6,421,383 points

Manfred Wolf DJ5MW – Germany
Stefan von Baltz DL1IAO – Germany

Award winners

Highest SSB (with >35% QSOs on CW)

K1M (IK1HJS/I4UFH) SSB – 2063 CW – 1233

Highest CW (with >35% QSOs on SSB)

N1S (LX2A/YO3JR) CW – 2391 SSB – 1302

Highest Multiplier

K1A (N6MJ/KL9A) 436

Best Accuracy

W1P (DJ5MW/DL1IAO) 1.0% error rate

The final results were very close with only 118,425 points separating the 3rd through 5th place teams. To give you an idea of how close this really was – only 6/10 of a multiplier or about one minute of operating time separated the 3rd and 4th place teams! Some of the operators achieved peak rates of over 300 contacts per hour. This is very impressive considering that Field Day style stations with 100W output were used by the competitors.

WRTC Tower And Antennas At Sunset

Our WRTC 2014 experience was a very memorable one. It was a great combination of amazing people, the best contesters in the world, great application of Amateur Radio technology and some of the best logistics and organization of a large event we’ve ever seen. Truly an Amateur Radio experience of a lifetime!

– Fred (AB1OC)

ARRL Centennial Convention This Week – Come Join Us In Hartford!

July 16, 2014 by AB1OC

ARRL Centennial

Anita (AB1QB) and I will be attending the ARRL Centennial Convention in Hartford Connecticut, USA this coming weekend. We are looking forward to seeing the vendor exhibits, Contest University and the many fine forum presentations which are scheduled.

Station Design Presentation

I will be doing a presentation on the design, construction and operation of our station at the ARRL Centennial event. My presentation is scheduled for Saturday, July 19th at 11 am in Room 27 at the Connecticut Convention Center. I will be presenting the complete story of our station from planning and design, through construction and finally how the station operates and performs. The presentation will include lots of high-resolution pictures and video including material on our shack, tower and antennas.

Updated Station Tour

The presentation will include lots of new material covering all of our recent projects as well as an updated virtual station tour.

Latest Antenna Projects

Some new topics will include our latest antenna projects and some information on our recently completed LEO Satellite System.

Station Automation Overview

The presentation will also include information on our recently installed Station Automation System from microHAM.

Current Station Performance

We plan to talk about how our station is performing against our original design goals and we’ll have some updated video too!

For those who are attending the ARRL Centennial Convention in Hartford Connecticut, I hope you stop by and say hello to Anita and me. We’re anxious to meet as many of our readers as we can at the event. For those who cannot make the trip, we will be taking lots of pictures and we plan to post a summary of what we saw here after the event.

– Fred (AB1OC)

LEO Satellite System Part 2 – Antenna Assembly And Ground Test

June 24, 2014 by AB1OC

Assembled Eggbeater Satellite Antenna System

We continued our project to add LEO Satellite capability to our station this past weekend (you can read about the design of our LEO Satellite System here). With 370′ of 7/8″ Hardline Coax (LDF5-50A) ordered and with Matt Strelow, KC1XX of XXTowers scheduled to help with the antenna installation on the tower later this week, the only prep work left was to assemble our M2 Eggbeater Antenna System and preamps and test the setup. The first rule of tower work is to assemble and test as much on the ground as possible. To this end, we decided to mock-up the entire antenna system a few feet up from the base of our tower. The first step in the process was to assemble the M2 Eggbeater Antenna System. This step was not difficult.

Ground Pre-assembly And Test

We next assembled a Rohn sidearm mount and attached it to our tower about 5 feet from the ground. We then mounted the antennas and cross boom on the sidearm mount and did some SWR sweeps on just the antennas with a RigExpert Antenna Analyzer to ensure that the they were performing to specifications. Both antennas checked out just fine. They both had SWR readings of 1.2 or less across a very wide bandwidth.

Satellite Preamp System Mock-Up

The final step in the pre-assembly process was to mount the preamp system that we had assembled previously to the tower. We also built all of the coax cables needed to connect the system from the planned 7/8″ Hardline Coax Feedlines (LDF5-50A) through the preamps and to the antennas. We used LMR-400UF Coax for these jumpers along with crimp-on N-connectors (we crimp and solder the pins on these connectors to the inner conductor of the coax to improve reliability). We installed heat shrimp tubing to seal the connectors in the crimp ferrule area and then covered all of the exposed connectors with electrical tape and CoaxWrap sealing tape. We also installed a 200′ length of DX Engineering Heavy Duty Control Cable (DXE-CW8-HD) to the preamp system. With these steps done, we again verified that the SWR performance of both antennas checked out within specifications.

I plan to pre-install a run of control cable from the control line surge protectors at the base of our tower to the shack and hook the control cable up to our M2 Antenna Systems S3 Sequencers sometime later this week. With these steps done, we will be ready to put our LEO Satellite System on our tower and perform the final integration and testing steps with the rest of our station.

Station Automation Part 2 – Second Operating Position And Antenna Switching

March 18, 2014 by AB1OC

microHAM Gear At Second Operating Position

microHAM Gear At Anita’s (AB1QB) Operating Position

We have continued our work on automating our station’s operation using microHAM equipment. I have integrated the second operating position into our station into the system via the installation of a second microHAM MK2R+ SO2R interface and two more Station Master Deluxe (SMD) antenna controllers. This position has a Yaesu FTdx5000 Transceiver and an Icom IC-7600 Transceiver. The integration of the FTdx5000 was straightforward and involved a cable hookup to the transceiver. I will add the Icom IC-7600 once the interface cable arrives here.

Current Antenna Control Stack

We’ve also begun to integrate the control of our antenna equipment into the microHAM system. I’ve moved our three SteppIR SDA100 controllers for our two SteppIR DB36 Yagis and our BigIR Vertical, as well as the two Green Heron RT-21 rotator controllers to a set of microHAM DATA control boxes (all of these devices have RS-232 interfaces). With these steps complete, any of our four radios can control the Rotators or provide frequency data to automatically tune our SteppIR antennas.

Antenna Switching Matrix

The biggest part of this project is the construction of a 4 x 10 antenna switching matrix. This element of the system allows any of our 4 radios to connect to any of up to 10 antennas. We built the Antenna Switching Matrix on a 4′ x 8′ board mounted on the wall outside our shack. As you can see from the picture above, this step required quite a few control cable connections as well as the construction of 40 coax interconnect cables (LMR400 Coax and crimp-on connectors were used here).

microHAM Ten Switch

Our Antenna Switching Matrix uses a set of microHAM Ten and 4+4 antenna switches along with multiple RELAY10 control boxes for control.

Antenna Switch Matrix SWR Test

It’s important to test an element like this as it is constructed to catch any errors and to ensure that the final system performance is as expected. I did a combination of continuity, voltage, and end-to-end SWR measurements on the Antenna Switching Matrix as it was built. The microHAM control boxes have a nice manual mode that is available via their front panel buttons which allowed me to configure each antenna switch manually to fully test all of the coax and control cabling in the system.

Receive Antenna Splitter And LNAs

Our antenna farm includes a steerable 8 Circle Vertical Receive Array for the low-bands, and we decided to create two separate appearances of this antenna on our switching matrix. This approach allows two different transceivers to use the receive antenna at the same time. This involves splitting the incoming signal from the receive antenna using a 2-port Splitter from DX Engineering. We also decided to include a pair of Low-Noise Amplifiers (LNAs) to boost the signals from the splitter before feeding the received signals to our antenna switching matrix. The Splitter and LNAs are 75-ohm devices. The signals are passed through a pair of 75-ohm to 50-ohm transformers from Wilson to match their 75-ohm impedance to our 50-ohm antenna switching system and feed lines. The SMD(s) control the LNAs, which have the associated receive antenna connection selected at any given time. This way, an operator can turn off the LNA at their SMD if they don’t need the extra amplification.

Antenna Matrix And Receive Antenna Control

All of this antenna switching requires quite a number of microHAM control boxes. We are also planning to terminate our 8 Circle Receive Antenna’s control lines at this point in our system. The receive antenna requires control leads to steer its direction and a sequencer capability to ensure it is not damaged by strong signals from other nearby transmit antennas. The microHAM system handles these functions easily via a combination of RELAY10 and RELAY6 control boxes, the units in the upper row in the picture above. These boxes also control the two receive LNAs.

With these steps done, we must complete the hookups of our Switchable Band Pass Filters and amplifiers to their associated SMDs. With that done, we can begin moving the feed lines for our antennas and radios over to the system. This will be the topic of our next article. For more information on our automation project, you might want to look at these articles:

– Fred, AB1OC

2013 Amateur Radio Highlights

February 9, 2014 by AB1OC

DXCCs Worked in 2013

Anita and I were quite active on the bands in 2013. Together we made 20,650+ contacts from a combination of our home and mobile stations and we worked a combined 259 DXCC Entities.

Combined 2013 QSOs By Band

We were active on all of the Amateur Bands available in the USA from 160m through 70cm except for the 60m and 1.25m bands. The picture above shows the distribution of our QSOs across the bands in 2013. Both of us participated in quite a few contests in 2013 and this resulted in the 5 major contest bands dominating our operating activity. I did quite a lot of work on the 160m band this year and I participated in several 160m contests to gain experience and to begin working towards a DXCC on this band. We worked a total of 50 DXCC Entities on 160m in 2013. Our 6m, 2m, and 440 MHz (70cm) contacts were made mostly during VHF/UHF contests that I participated in.

Combined 2013 QSOs By Mode

We like to operate using many different modes. Anita (AB1QB) does quite a bit of RTTY contesting and she accounted for the bulk of the activity in the digital modes from our station in 2013. I made it a point to become active using the CW mode this year and I made 1,550+ contacts using CW in 2013 including participation in several CW contests. Operations in SSB Phone mode dominated our activity this year mostly due to our operations in SSB Phone contests and as one of the New Hampshire Stations in the 2013 Colonies Special Event this year where we made a combined total of 6,200+ contacts.

QSL Cards Ready To Mail

We really enjoy sending and receiving QSL cards. We sent 5,800+ QSL cards this year, averaging approximately 110 cards sent each week. We also QSL’ed via eQSL and Logbook Of The World. I am often asked what percentage of our QSL requests are confirmed. For 2013, we received confirmations for 67% of our direct/bureau cards, 31% of the QSOs uploaded to eQSL, and 37% of the QSOs upload to LoTW. These numbers will undoubtedly rise a time goes by.

AB1OC Operating Awards

All of this operating allowed us to complete a number of operating awards this year. Fred completed his DXCC Challenge, 8-Band DXCC, and CQ WPX Award of Excellence Awards as well as a DXCC Awards in CW mode and a DXCC QRP (5 watts).

AB1QB Japan Century Cities Award

Anita has held a DXCC for some time and has been focusing on a number of JARL Awards. She completed her Japan Century Cities Award for confirming contacts with 100 cities in Japan in 2013.

AB1QB Operating In The BARTG RTTY Contest

Contesting was a big part of the operations from our station this year. I was active in several major SSB and CW contests this year and Anita was active in quite a few major RTTY and phone contests as well. We are both licensed for less that 3 years and have been competing in the Rookie or Novice categories in most contests and we have been doing quite well. Anita took 5th place in the world in the 2013 BARTG RTTY Contest and she has placed 1st in our call area in several of the 2013 ARRL Rookie Roundups in both SSB Phone and RTTY.

2013 CQ Worldwide WPX SSB Certificate

I placed 1st in North America/2nd in the World in the 2013 CQ WPX SSB Contest (Rookie High Power) and 1st in North America/2nd in the World in the 2013 CQ WPX CW Contest (Rookie High Power). Contests have provided us a great deal of operating experience and have contributed greatly to our completion of several operating awards.

Mobile Installation In Ford F-150

Station Building was a big part of our Amateur Radio experience again in 2013. We installed a mobile HF setup in our truck and did quite a bit of mobile HF operating. We made 165 contacts from our mobile station in 2013 and worked 41 DXCC entities.

WSJT EME QSO – Waterfall

I also made my first Earth-Moon-Earth Contacts on 2m in 2013. I made 30 contacts on 2m using the moon as a reflector, working a total of 16 DXCC Entities this way.

AB1QB Operating The Flex-3000 Software Defined Radio

We added a Flex-3000 Software Defined Radio (SDR) to our station in 2013 and have been using it to learn about this new technology. The performance and operating capabilities of SDR are making SDR a big part of the future of Amateur Radio in our opinion.

8-Circle Receive Array System Diagram

Antenna projects were also a part of our station building work in 2013. We installed an 8-Circle Receive Array System for 160m – 40m and this new antenna system helped us a great deal with DX’ing and contesting on 160m and 80m. We also began the reinstallation of our BigIR Vertical Antenna but the onset of winter here in New Hampshire caused us to delay the completion of this project until spring. Finally, we made the switch to the excellent DXLab logging and DX’ing software suite. DXLab helped us a great deal with QSL’ing and tracking our progress toward operating awards.

2013 Field Day CW Station Operations

We were part of the 2013 Field Day team at our local radio Club (PART in Westford, MA). We provided and managed the digital station as well as the setup of a portion of the antenna systems for our club’s field day operations.

ARRL At Dayton 2013

Anita and I attended the Dayton Hamvention again in 2013. The Dayton event is always a great opportunity to see the latest in Amateur Radio equipment. We attended the 2013 Contest University which was held as part of the Dayton Event and used the information that we learned there to continue to improve our contesting skills.

Fred Lloyd AA7BQ, Founder Of QRZ.com

The internet was a big part of our Amateur Radio experience again in 2013. We met Fred Lloyd, AA7BQ who visited us to do an article on QRZ.com on our station. We learned a great deal from Fred during the time that we spent with him as part of this project. We published 47 new articles here on our blog in 2013 and have received over 45,000 views from our readers in 152 countries around the world. We really appreciate the interest from the HAM community and we will continue to publish new articles here in 2014.

As you can tell from this article, 2013 has been a very active year for Anita and I. I’ve created the video above to give you some idea of the contacts that we have been fortunate enough to make around the world in 2013. We hope you enjoy it and we want to thank everyone who has taken the time to work us, to end us a QSL card or to read the articles that we have written here.

– Fred (AB1OC)

First QSOs On The 60m Band

January 23, 2014 by AB1OC

60m Band Plan (from ARRL Band Plan Chart)

The 60m Band is a relatively new allocation for Amateur Radio Operators in North America. I’ve long wanted to try this band so last evening I took some time to understand what was required and to determine if my available antennas were up to the task. U.S. Amateur Radio operators with a General Class or higher license have secondary privileges on the 60m band. U.S. HAMs can use either USB Phone, CW, or a limited set of digital modes on 60m. The band is “channelized” meaning that one must operate on specific frequencies only. For Phone communications, one must use USB mode only, limit the bandwidth of your signal to 2.8 kHz (most rigs operate USB at a 2.4 kHz bandwidth) and you must set your rig’s frequencies to one of the values shown above corresponding to the five available channels. These same frequencies/channels would be used for digital modes such as PSK31 or RTTY (see the article on this blog for information on how to get started if your interested in operating using digital modes). For CW operation, you need to set your rig to 1.5 kHz above the frequencies indicated above which will ensure your CW signal is in the center of the associated channel. The highest frequency channel (5403.5 kHz) is shared by HAMs in the U.K. and often provides opportunities to work DX on 60m.

There is an 100W Effective Radiated Power (ERP) limit on this band. See the following page on the ARRL site for information on channel allocations and operating tips. There is also an excellent 60m FAQ page on the ARRL site.

*** Note that this information was taken from the ARRL website and is presumed to be correct for U.S.-based HAMs at the time this article was written. I recommend that you consult the ARRL website or the equivalent source for license information in your home country prior to operating on 60m to obtain the most up to date operating privileges and rules for the 60m band as they pertain to your home country and license class ***

DXLab Commander 60m Setup

Most modern rigs can be tuned to the frequencies used on the 60m band. To make this easy to do and error free, I configured the rig control application in the DXLab Logging Suite which I use to set my transceiver to the correct frequencies, bandwidths and modes corresponding to the five 60m channel allocations for Phone/Digital and CW.

75M Delta Loop On Tower

The next step was to determine which of my available transmit antennas would work on the 60m band. After some checking with an antenna analyzer, I determined that the 75m Delta Loop on our tower would tune up well enough to use as a 60m transmit antenna (the feed point for the Delta Loop is on the white fiberglass rod which protrudes to the left of the tower about 15 ft up in the picture above and the apex of the loop is suspended from the upper set of guy cables). I also have a SteppIR BigIR Vertical which will work on 60m but I don’t have that antenna completely installed yet.

The 100W ERP power limit on the 60m band is relative to a Dipole antenna with 100W PEP in. If your antenna has gain relative to a dipole your must adjust your power out accordingly. For example, if your antenna has 3 dBd (3 dB gain relative to a dipole), then you’d be limited to 50W PEP output (50W PEP out + 3 dB gain = 100W ERP). You can use the following link to a handy dB calculator to help you do this calculation if your antenna requires it. Also note that you are required to maintain records based on manufacturer’s antenna gain specifications or equivalent information for your 60m transmit antenna.

8-Circle Low-Bande Receive System

The Delta Loop also makes a fairly effective receive antenna on 60m. Fortunately, we installed an 8-Circle Directional Receive System for 160m – 40m this past summer and this system works very well as a directional receive antenna on 60m. The 8-circle System has about 10 dB Front to Back performance on the 60m band and is considerably less noisy than the Delta Loop.

I could hardly have picked a better time to begin operating on 60m. It turned out that Canada had just granted 60m privileges to Canadian HAMs on a broad basis on the same day! This will no doubt create many additional opportunities for contacts on the 60m band. Wikipedia provides an excellent overview of regulatory information associated with the 60m band as well as up to date information on countries which provide 60m band privileges around the world. My very first contact on 60m was a phone QSO with Joe VE3BW in Ontario, Canada. I was also able to work some additional DX including Dragan 9A6W in Croatia, Bo OZ8ABE in Denmark, and Rick, G3XAJ in the U.K. The best part about the 60m band is the relaxed atmosphere I found there. I encountered many HAMs were willing to have a nice conversation and this coupled with surprisingly quiet band conditions made the 15 or so contacts that I have completed to date on 60m a very positive experience.

I’d encourage our readers to give 60m a try. Many antennas such as OCF dipoles, G5RVs, open-wire fed dipoles and long wires will tune up reasonable well on the 60m band and the 100W ERP limit is a good equalizer for small and medium HF stations. I hope to work you on 60m in the near future!

– Fred (AB1OC)

SteppIR BigIR Vertical Antenna Part 1 – Assembly & Installation

November 12, 2013 by AB1OC

SteppIR BigIR Vertical Antenna

When we installed our new tower-based antenna system last year, I was forced to take down our SteppIR BigIR Vertical Antenna to make room for the tower. We really miss having the BigIR Vertical because it provided omnidirectional coverage on all of the HF bands from 80m – 6m and is a good DX antenna due to a vertical antenna’s characteristic low-takeoff angles. The SteppIR BigIR Vertical uses a stepper motor to move a length of beryllium tape up and down inside a hollow tube effectively changing the electrical length of the antenna to tune it. The antenna also has an optional Switchable 80m Loading Coil which allows the antenna to be tuned for the 75/80m band as well. The adjustment of the length of the antenna and the coil is handled by a controller in the shack which reads the frequency of an associated radio and automatically adjusts the antenna as the radio is tuned.

Antenna Layout Plan

We decided to re-condition and re-install our SteppIR BigIR Vertical in the woods in front of our house. This location was chosen as it provides adequate separation between the BigIR and our other transmit and receive antennas and is at a high spot on our lot. This area is also surrounded by some fairly wet ground which should enhance the performance of the BigIR Vertical Antenna.

Vertical Antenna Foundation

The first step in the installation of the antenna was to dig a hole for and pour a concrete foundation for the antenna. All of the needed materials as well as a rental motorized post hole drill were obtained at our local home supply store. We used an 8″ round form and dug down approximately 3 feet into the soil to set the form. We then placed about 6″ of medium stone in the bottom of the hole and filled the form with cement. We set and plumed a piece of 2″ plastic PVC pipe in the center of the form to hold the steel pipe that mounts the BigIR Vertical Antenna.

Foundation And Base Mounting Details

The PVC pipe is slotted on the ends with a saw so that it will clamp and hold the BigIR mounting pipe firmly in place with the aid of two stainless steel hose clamps. The mounting pipe that comes with the BigIR is slightly smaller in diameter than the inside of the PVC pipe so a few layers of electrical tape are used at three points on the mounting pipe to create a good fit. This approach allows the antenna and the associated mounting pipe to be removed from the foundation for use at another site if needed.

Vertical Antenna Radial Plate

The next step in the installation was to assemble and mount a DX Engineering Radial Plate. This Radial Plate is an excellent part and will make it easier to attach the planned 120 radial wires to the antenna. I am using N-connectors on all of the feedline connections associated with our BigIR Vertical so I also installed a N-connector Feed Through Connector on the radial plate to enable easy grounding of the feedline coax’s shield to the radial plate and antenna.

BigIR Pre-Assembly – Element Support Tube (EST) Joint Sealing

The next step in the installation was to re-assemble the BigIR Vertical Antenna. The paint on my element housing tubes had faded quite a bit so I lightly sanded them and sprayed them with a couple of coats of Krylon U-V Resistant Clear Coat. This made the tubes look like new and provides protection from fading and weakening of the element tubes due to the effects of UV radiation. SteppIR has made several enhancements to the BigIR since I purchased it a few years back. These include a much better sealing system for the element housing tubes which makes use of heat shrink tubing (pictured above) and a High-Wind Reinforcing Kit for the antenna’s element housing and base. These updated parts and components were obtained from SteppIR for use in re-assembling the antenna. SteppIR has also improved the assembly and instruction manual considerably.

BigIR Wind Reinforcing Kit With Element Housing And Coil

I first connected one end of a spool of 4 conductor control cable to the element housing and reassembled the antenna’s element housing, 80m coil, optional feedline choke balun and the wind reinforcing plate and saddles.

BigIR Pre-Assembly – Base With Both Sections Of Element Support Tubes

Next, I attached the lower section of the element support tubes to the base assembly. I also prepared the upper section of the element support tube by sealing the joints, attaching the guy rope bracket and installing the top cap/vent and rubber coupler. The antenna is over 30 feet in length when the fully assembled so its best to leave the antenna base/lower element housing tube and the upper element housing tube separated to make transporting the antenna to the site where it will be installed easier.

After transporting the pre-assembled antenna to the installation site, I next attached three lengths of Dacron Antenna Guy Rope to guy rope bracket on the antenna and assembled the two sections of the element support tube to each other, completing the assembly of the antenna.

Coupler UV Protection

It is a good idea to cover the rubber coupler which attaches the upper and lower element support tube sections together with several layers of electrical tape to protect the rubber coupler from UV damage.

BigIR Installed On Foundation – 80m Coil And Balun

Next I carefully lifted the antenna onto the foundation, attached the three guy ropes to their anchors and then torqued the saddle clamp bolts on the wind reinforcing bracket to 12 ft-lbs. It’s important to not over tighten the saddle clamp bolts as doing so can crack the fiberglass tubes on the antenna. The next step was to tighten the lower rubber coupling clamps, sealing the antenna’s connection to the metal tubing in the foundation.

BigIR Grounding Details

The last step in the antenna installation was to connect the ground lug on the 80m coil to the radial plate using a DX Engineering Ground Strap.

BigIR Installed On Foundation – Element Housing And Control Cable

The picture above shows the element housing side of the installed antenna. The spool of control cable will be covered with a plastic bag to protect it from the weather until the final feedline and control cable connections are run to the shack.

Guy Rope Anchor

The picture above shows the details of the guy rope anchors used to secure the guy ropes on the ground. Three Earth Anchors were turned into the soil using a steel rod which provides a solid point to attach the three guy ropes. The rope tension adjusters shown in the picture above were obtained from our local hardware store.

A Stealthy Vertical Antenna In The Woods

As you can see from the picture above, the BigIR Vertical is quite stealthy when installed in the woods. While it may not seem so, the work outlined here represents the easy part of a vertical antenna installation. The real work lies in installing the radial wire field around the antenna. The radial field has a significant impact on a vertical antenna’s performance in terms of both radiation efficiency and takeoff angle. The ground in our area is not very good so I am planning to install an extensive radial field consisting of 120 radial wires, each 110 feet in length. I will cover this part of the project along with the installation of the feedlines and control cables to the shack and the final integration and testing of our BigIR Vertical Antenna System in a future article.

– Fred (AB1OC)

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