MISSISSIPPI RADIO DIRECTION FINDING ASSOCIATION'S FIRST T-HUNT

After a week of freezing (and sub-freezing) temperatures, ice and snow, Saturday turned out to be a spectacularly beautiful day, with sunny clear skies and spring-like temperatures in the mid 50s.

In Scott County the ice and snow had almost all melted and the roads were clear and dry making it easy to drive.

After a week of being cooped up in the house it was a perfect day toget out an enjoy a T-Hunt.

At 7:30 am K1REZ hid the transmitter in a tree within the public right of way along a rural county road and turned it it. It began transmitting a series of dashes and dits which was Morse Code for MOE, the typical name of the first (or only) transmitter in a T-Hunt. After 30 seconds it transmitted K1REZ’s callsign ID, then went silent for 15 seconds before repeating the cycle. This continued until the end of the hunt time limit at 8:00 pm.

The transmitter K1REZ used was the 15 mW MicroFox15 transmitter made and sold by Byonics.com

K1REZ had initially placed a compact vertical on the transmitter when testing out the boundary range earlier in the week. However, on the morning of the hunt, he decided to use a horizontally polarized miniature dipole antenna. The dipole measured 37 inches long and was made out of piano wire. This antenna added about 2 miles to the already 1-2 mile range of the vertical antenna.

With the dipole antenna, the transmitter signal could now be heard along both interstate 20 and highway 80 from the town of Pelahatchie to the town of Morton. This provided many locations for taking bearings on the transmitter, which was hidden in a rural area between the two highways and the two towns.

Sometime during the morning, KI5HGX and his wife left their ice-laden neighborhood in Rankin County and headed to ice-free Morton to begin their hunt. They used an interesting mix of home brewed equipment and were the first to find the transmitter. After signing the logbook, they grabbed the 1st place medal and the grand prize, which was the $60 ARRL Handbook for Amateur Radio Communications, and left the scene with smiles on their faces. They also will be receiving a free membership in Mississippi Radio Direction Finding, and participation points toward MSRDF certificates.

After the T-Hunt time limit ended, K1REZ retrieved the transmitter and the T-Hunt box, and noted that no one else had signed the log sheet, or retrieved the 2nd and 3rd place medals. We are not yet sure if that means that several others hunted for the transmitter and were not able to find it, or if KI5HGX and his wife were the only hunters that day. However, K1REZ monitored the T-Hunt frequency from 8:00 am until 8:00 pm and they were the only hunters he heard from.

If you missed this event, kick yourself, because you would have had a great time on a beautiful, sunny day in the country. We have plenty more radio direction finding events planned for you to enjoy, so check out our calendar.

KI5HGX TELLS US ABOUT HE AND HIS WIFE'S T-HUNT ADVENTURE

We really enjoyed our first experience of a T-hunt during the February event. My wife and I heard about it a few weeks prior and decided to give it a try despite not having any experience or directional equipment. I built a version of WB2HOL’s tape measure yagi for the antenna. My handheld has no S meter and I don’t have an attenuator so I decided to use a SDR (software defined receiver) Nooelec NESDR dongle from Amazon that I had laying around. Combining this with a Raspberry Pi computer and some free software called Cubic SDR  gave me the ability to tune, see the signal on a spectrum and attenuate the strength.

Our strategy for the hunt was to start near the center of the mapped area and sweep to decide on what quadrant to focus our efforts. The HT picked up a signal near our start area and a quick spin of the yagi indicated a direction up the same road. After a bit of stumbling, we narrowed the area and the yagi even told us which side of the road to search and be the First to Find!

The SDR, although a bit cumbersome worked super and we discovered that a tape measure yagi design, if held out the vehicle window above 20 mph, rolls itself into a non-functional mess.

FEBRUARY 20, 2021 T-HUNT DETAILS

What: T-Hunt

Type: Mobile (with a 25 foot walk from the parking spot to the T-Hunt Box)

When: Saturday, Feb 20, 2021

Where: In and around Morton, MS

Time Limit: 8:00 am - 8:00 pm

Hunt Coordination Frequency: Pelahatchie Repeater: 145.390 77 Hz

K1REZ will be monitoring this frequency throughout the event if anyone needs assistance. If you have a transceiver with you, please contact K1REZ when you arrive at the Suggested Start Location. This frequency may also be used for cooperative coordination by teams during the cooperative phase of the event.

Hidden Transmitter Frequency: 146.565 simplex

Transmitter Power: 15mW

Transmitter Cycle: The transmitter will repeat the following cycle:

45 seconds of transmission (MOE), 3 seconds of ID (K1REZ), 13 seconds of silence.

MOE is the standard transmission for the first (or only) transmitter in a T-Hunt.

MOE in Morse Code is: -- --- · (Dash Dash, Dash Dash Dash, Dot)

Antenna Polarization (Vertical or Horizontal): Not Given. (Use your RDF Skills to figure it out)

Hunt Boundary: The transmitter is hidden in the public right-of-way somewhere within the 3 mile area marked in red on the boundary map. Your vehicle will get you to within about 25 feet of the transmitter. It is NOT hidden at, or within walking distance of, the two recommended starting locations. Those are just good places to take initial bearings for triangulating on the transmitter.

Boundary Map: See boundary map on the last page of document. (You will also need access to a road map of the area: a GPS, Smart-phone Navigation, Google Maps, Mississippi State Map, Mississippi DeLorme Map Atlas, Scott County Map, USGS Quad Maps, or make your own map)

Good Starting Locations for taking Initial Bearings:

On I-20, on the drive east toward Morton Exit (77) a good mobile vertical antenna will start picking up the signal around mile marker 74. (Do NOT stop on the highway to take bearings, instead proceed to the following two good starting locations to get your initial bearings.)
Strong Signal: N 32° 18.371 W 89° 41.918
Weak Signal: N 32° 18.865 W 89° 40.091

Driving Directions: From the Jackson/Brandon area, take I-20 heading East to the first Morton Exit (Exit 77). Turn left onto highway 13. This will put you in the Morton arae.

Awards: 1st, 2nd, and 3rd place medals for the first three finders (only one medal per vehicle). Additionally, the first person to find the transmitter will also receive the 2021 edition of “The ARRL Handbook for Radio Communications” (a $50 book).

Special Instructions:

Goal: Your goal is to find the T-Hunt Box and sign the Log Sheet inside it. The T-Hunt Box will be clearly visible when you arrive near Ground Zero. The transmitter itself is not inside the T-Hunt Box, but is very close to it, and has instead been camouflaged and carefully hidden to prevent tampering and theft. Like on ARDF Hunts, you most likely will never see the transmitter. However, if you find the T-Hunt Box, you have found the transmitter. If you do happen to spot the transmitter's hiding spot, do not touch it. (For security, an equally well camouflaged deer camera will also be nearby watching over the transmitter. Don't embarrass yourself.)'

Teams & Medals: If you, or your team (everyone riding in the same vehicle is one team) sign on the 1st, 2nd, or 3rd place line on the Log Sheet, then please take the Medal associated with that place. Don't leave the medal in the box, because that would confuse the next finder. (Remember, only one Medal per team, regardless of how many persons are in the vehicle, and regardless of how many vehicles your team utilizes. If you don't want to share the glory or the medal, hunt by yourself.) Additionally, the first person to find the transmitter will also receive the 2021 edition of “The ARRL Handbook for Radio Communications” (a $50 book), which will be in the T-Hunt Box waiting for you to grab it. Please sign the log book first.

Competition vs. Cooperative Effort: During the first six hours (8 am - 2 pm) of the Hunt this event will be a Competition. Every vehicle is considered one team. And all teams are in competition against each other. Therefore, do not assist other teams during the first six hours of the hunt.

During the last six hours (2 pm - 8 pm) of the Hunt teams are allowed to cooperate with each other, if they so desire.

During the last hour of the event, K1REZ will be available on the radio for hints, and as a last resort give out the exact GPS coordinates to persons having trouble finding the transmitter.

If you hunt after dark, bring a good flashlight.

How to handle Muggles: If any Muggles (persons who are not in on the hunt) ask you what you are doing, tell them you are an FCC licensed Amateur Radio Operator hunting for a transmitter. Do not reveal to them the exact hiding spot of the transmitter.

MSRDF.com Points toward Certificates: All members of MSRDF.com who sign the Log Sheet in the T-Hunt Box will receive points toward various MSRDF Certificates.

For more details and T-Hunt Rules visit: MSRDF.com

Send Questions to: info@MSRDF.com