South Arm Stage NEFR Radio Challenge

South Arm NEFR – A Tough Radio Challenge

South Arm ME topo map

This is the actual South Arm racecourse. The black letters A-J are radio operator positions.

The South Arm and Icicle Brook stages of the New England Forest Rally (NEFR) present challenging communications issues for radio operators. The communications for this gravel-road racecourse have been done for years using 2-meter simplex. This radio frequency is considered very high frequency (VHF) as it’s in the 144-148 MHz part of the radio spectrum.

This racing event features powerful cars that go very fast. Drivers, their support teams, and spectators rely on lightning-fast communications during the event.

It’s important to realize that when one radio operator transmits during the rally, it’s imperative all other operators on the course hear that transmission.

Radio Relaying = Recipe for Disaster

Radio operators are spread out along the route and in the past the start (radio position A) and finish (radio position J) officials have had to rely on a relay operator as you see in the second topographic map image below. The relay operator is where the blue hexagon symbol is on the map.

The relay system works because the 2-meter signal can slip through the notch on the east side of the tiny mountain. Look at the topographic map below and you can clearly see how there’s a direct pathway between the start and the relay operator’s position. However, relaying messages slows things down and it becomes a huge handicap in an emergency.

A Fresh Perspective

I was asked to take over the chief of communications for the NEFR beginning in 2018. It was a baptism by fire and I had never even been to South Arm before. The leadership of the rally told me they’ve always had comms problems at South Arm and once I arrived I could see why. There was a formidable small mountain in the middle of the racecourse. The radio frequency, 2 meters, they had been using for years doesn’t play well with mountains!

If you want to get over mountains with 2 meters, you need antenna height and power. Many NEFR volunteer radio operators in the past only had Technician privileges and radios that could primarily transmit and receive on 2 meters. It was time to try a different approach. After the 2018 rally, I conducted an exit survey and discovered most of the operators had no high-frequency (HF) experience.

I decided it was time to recruit some experienced HF operators who would work with me to solve this communications conundrum. It’s imperative that the problem be solved because the NEFR is a world-class event with some drivers coming from different countries to race. We must provide a reliable communications system for them, the race teams, spectators, and all volunteers.

Believe me, bad things can happen during the NEFR. Watch this video to see why we need to have reliable communications:

What is the Primary Problem?

Look at the topographic map below and pay attention to the steep hill/mountain inside the red circle. The top of it is 1,200 feet higher than the roadway at the start and finish of both stages.

This map includes the South Arm and Icicle Brook stages of the NEFR. The red balloon at the bottom is at the approximate start of South Arm and the finish of Icicle Brook. The purple star is the finish of South Arm and the start of Icicle Brook. The blue hexagon is an ideal location for a radio relay position. The red circle identifies the wretched mountain that tops out around 2,700 feet above sea level (ASL) while the stage roadway hovers around 1,500 feet ASL. Do you think for a moment a 5-watt HT has a chance to conquer this conundrum? Copyright 2019, Google, Inc.

What Can Be Done to Ensure Clear Communications?

You need a tall antenna and lots of power to get a signal from the start to the finish if you intend to conquer the mountain using simplex VHF transmissions. The distance between the start and finish as the crow flies is just under ten miles!

A repeater could be located across Upper Richardson Lake about 2/3rds of the way between the start and finish of the two stages. At this location, it would have a very clear shot of all radio operators along both stages. The tall mountain would not hinder communications whatsoever.

You can also put a repeater in a circling airplane or suspended from a tethered balloon. Both of these options create their own set of very specific problems, not the least of which is cost.

Are Repeaters the Answer?

There are other significant issues with repeaters. Here are but a few of the challenges:

Repeaters offer up a sole point of failure. If the repeater fails during the stage no one can communicate. With the current simplex setup, if one operator’s radio or antenna fails, only his position is affected.

Duplexers can be sensitive. They are required in a repeater to make the same-band repeat magic happen. These cans usually don’t like being bumped around traveling on gravel roads that have more potholes than Dunkin has doughnuts.

The provider of the repeater has to set up the repeater, controller, duplexers, etc. as well as the antenna in a short amount of time before the stages run.

The repeater location across Lake Richardson may not be accessible just before the rally. The roads may get washed out and the owner of the road may not repair it in time nor want to invest the money to repair it.

The repeater location at the top of the mountain in between the start and the finish has no road, no trails, and it’s extremely tough hiking with all the needed equipment. Keep in mind the need for the repeater is but six or seven hours. The people working this event are unpaid volunteers and to expect someone to backpack all that gear up to the top of the mountain is a lofty expectation!

What About an HF Solution?

Yes, you might have great success using high frequency (HF) on 80 meters. It’s even possible to get a NVIS signal on 40 meters. All operators would have to have HF equipment and be able to deploy an 80-40M Near Vertical Incidence Skywave (NVIS) antenna.

The US military relies on NVIS operations in battleground situations. It’s that reliable.

A NVIS antenna can be just a simple thin wire suspended about 4-8 feet in the air. You can drape the antenna over tree branches or bushes. You can also use some simple wood stakes or inexpensive fiberglass electric-fence posts to hold it above the ground. I recently switched to these fiberglass poles/posts and they’re excellent.

Here’s a video I recorded in August of 2019 showing how easy it is to build and deploy this antenna. NOTE: This antenna set up flies in the face of the optimal theoretical antenna design created by fancy software. Realize that this antenna you’re about to see works VERY WELL. I urge you to try it yourself. You’ll be amazed that it works.

How About 10 Meters?

Ten meters is a very strong candidate to solve the vexing issue. It’s very close to the citizen’s band (CB) of eleven meters. This band has a respectable pedigree for traveling 30 to 50 miles out in the open plains. With altitude, it can go even farther.

The other benefit is the antenna is so much shorter. You can create a vertical center-fed dipole that’s just 16 feet 4 inches long! You can hang this from a tree with little effort.

Finally, those who only have Technician privileges can operate in the ten-meter band. This means any NEFR operator with a 10-meter radio can be assigned to the South Arm and Icicle Brook stages.

On October 10, 2020 I’m headed to South Arm with four other seasoned radio professionals who have worked South Arm before to test both 10 and 80 meters. I’ll be creating a separate blog post about the outcome.

UPDATE: July 22, 2019On Friday, July 19, 2019 I did an 80M NVIS test at the start and finish lines of this stage. I was assisted by Sean Tarbox, N1BOX, and Tim Foy, W1FOY. Sean and Tim, along with Tim’s wife Monica, were just below the start of the South Arm start line. I was a mile beyond the finish line of South Arm.

We established crystal-clear comms using a simple antenna that was about 2 feet off the ground at my end. I was only transmitting with 13 watts out of my Elecraft KX3. Sean and Tim experimented with different power levels up to 50 watts. At 50 watts it was if they were standing next to me. A stunning 5-9 signal report.

Watch these videos to get an idea of how easy it is to do NVIS comms:

If you have ideas, put them in the comments below.

 

 

10 thoughts on “South Arm Stage NEFR Radio Challenge

  1. I have been told that in the past a repeater was set up at the southern pulloff on route 17, a blacktop road overlooking the area. One year when I was the mid point human repeater in Icicle brook, I was intermittently unable to receive from start or finish, but clearly heard plenty of communications in Spanish from somewhere far south. Fortunately, another ham who really had his act together quickly figured this out and “filled in the blanks”. He must have been exactly the right distance away to be “180 degrees out of phase” with what was going on. Studying for my General. What 80 meter radio would you recommend?

    • I’ve heard great things about the Yaesu 857. I have an ICOM 7000 mobile HF radio, but it’s no longer made, but ICOM has other HF mobile radios now.

      You might consider using hamtestonline.com to get your General as fast as possible. Go to YouTube and watch my Ham Test Online Review video.

      It’s very important for you to get HF privileges as soon as possible and BEGIN to practice using them getting on the air months and months before NEFR 2020.

      What’s more, the only HF antenna we will be using at South Arm and Icicle Brook is the one I show in this video:

      https://w3atb.com/80-meter-nvis-antenna/

      Email me if you have any other questions.

      I will be announcing 80M NVIS practice sessions beginning in May once the WX is not so cold.

  2. Ok here is the deal I was at “B” south arm with my 18′ Diamond antenna on the back of my truck up about 9 feet. I was at about 1500 feet on the course I had to relay messages to start from the relay radio I heard everyone on the course. I also have HF in my truck and if I had known you were going to use HF and the freq I would have participated.

    • Tim,

      You had to relay because the Start radio operator made a decision on his own to NOT use the 40-foot-tall halyard I had put up in the tree next to the Start radio. That operator had a roof-top antenna. That won’t happen again, trust me.

      The HF was a simple test done by operators who were NOT working the stage. I made that decision on purpose. It would not have been prudent to have South Arm stage operators participating in a test when they’re supposed to be concentrating on the race and the VHF traffic. That’s why you didn’t know anything about the test.

      But no worries, if you have HF capabilities and want to work South Arm and Icicle Brook next year, you’re more than welcome. These two stages will be done with operators who have HF 80 meters and a simple NVIS antenna. They will also have VHF as a backup in case the 80-meter ground wave is not cooperating that day.

      • I don’t trust HF to be reliable particularly during the day. Regardless of the finish and perhaps inadequate antenna deployment I had no problem hearing everyone on VHF @ 1500′ And IMHO a good antenna, location and 50 watts you should be able to work in excess of 20+ miles.Our club repeater is at 1600′ I’m at 450 it’s 16 miles from the qth with about 20 watt trru the cans I can hear it it can hear me with a hand held. Most newish hams do not have HF and if everything needs to be relayed it slows things down. This is my take, years ago we used exactly the same antenna I brought it worked.

        • Tim,

          Well, we’ll find out next year how well the 80M NVIS will work. NVIS is so reliable the US Army and Marines rely on it for battleground comms. If you’re not familiar with NVIS comms, theory, capabilities, I suggest you start your education by reading this excellent NVIS primer.

          What’s more, with enough power, anything between 50 and 100 watts, you can generate a powerful groundwave that will crawl all over that pesky mountain.

          Based on my test last Friday, 80M NVIS should work very well. Have you ever made NVIS contacts? If not, don’t be so quick to pooh-pooh the proven concept. Since you have HF in your vehicle, I suggest you set up a simple NVIS antenna. I’m more than happy to tell you how to do it. You might be pleasantly surprised with the results.

          We will be using 80M NVIS as the primary comms for South Arm (SA) and Icicle Brook (IB) next year. We will use the current VHF system with a relay as a backup – but next year each operator will have all the correct equipment (see below for a list of what each operator will have to have). Without it, they will not be working these two stages. That’s my decision.

          You don’t have to worry about inexperienced operators next year. I already have six HF operators with deep HF experience, the required HF mobile radios, and all with rally experience. They were working with us this year. Over the next eleven months, I’ll recruit no less than six more. So put to rest your fear of inexperienced HF operators.

          What’s more, we’ll be probably relying on a ground wave with the 80M more so than NVIS bounce to the D layer. Propagation should not be an issue

          I talked for months about everyone having a j-pole that would be 40 feet up in a tree at their location on these two stages. You can go back and read my emails to all the operators and stage captains to prove how I recommended this.

          To the best of my knowledge, only one was used at the relay position. I put up a 40-foot halyard at both the start and finish of SA and IB. The stage captains, and or the radio operators at those locations, made the decision NOT to use them.

          That will never happen again. I will mandate that every operator has a 50-watt radio VHF connected to a 450-ohm ladder line antenna at least 30 feet up in a tree.

          I had a clinic on Thursday night to show people how to get the antennas up in trees.

          It’s a volunteer effort and I can’t force people to do things. But believe me, next year – should you decide to volunteer – the ONLY operators that will work South Arm and Icicle Brook will have:

          • 80m HF radio
          • NVIS antenna
          • 50-watt mobile VHF radio
          • 25-foot adjustable painter’s fiberglass pole
          • simple drive-on mast/pole support
          • 450-ohm j-pole with choke
          • 50 feet of coax to connect j-pole to the mobile radio

          You’re going to see another very specific questionnaire next spring that every operator has to fill out. They will list all the equipment they have.

          I’ll know a month before the rally who has what and who’s going to be working SA and IB.

          I’ll end with this. If you want to test your repeater theory next year at SA and IB I’m all for it. The repeater needs to be across Lake Richardson in a place that has a line of sight with all stations on both stages. You can see this easily on Google Maps.

          You’ve got 11 months at this point to gather all the equipment you need to test your repeater hypothesis.

          I’m happy to show you on the map where I feel the repeater should be placed. It’s your job to gather all the equipment, make it work, set it up, etc. I’ve not set up a repeater so I can’t help you with any of it.

          Let me know as soon as possible if you’re planning on doing a repeater test next year.

  3. I functioned as a relay on South Arm a few times – the location we used was close to where you suggested (North of the hexagon along that same road about even with the “2200” marking at a small dirt road that intersects from the East) it worked pretty well, but was not full coverage of the stage, even with my collinear. I wonder if the hexagon would be a bit better due to proximity to the stage start, which were the harder stations to stay in touch with. My setup compensated for a lot of the HT crowd, but some folks disappeared from time to time mostly due to DC power issues and not understanding how to ‘tune’ and maintain their position once I was in place as far as I could tell

  4. Well, if you can pull this off, fantastic. I’d say go for it. The best place for the repeater is across the lake as I describe above. You NEED to get in touch with Matt Kennedy the stage captain if you want to make this enormous investment of resources. I don’t have batteries nor the generator.

    • I can probably borrow a Honda EU2000i from work but if not I own my own 6000 watt generator I’d be willing to haul up.

  5. Again I can provide a repeater I have one on 145.45 PL of 100 with cans and probably can scare up an Auston antenna. Now it will need either a bank of batteries or a generator a Honda 2000 would do with a power supply. It is a mobile Motorola unit so either would work. We did a high gain Antenna one year and a mobile unit as communications point at the highest location it did pretty well. Unless people can park with their mobile units with some type of gain there are going to be dead spots. This is not something I can throw together quickly as the cans are on top of Mt Cranmore in NH right now so if you are interested I would need to know.

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