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Ohio Hams Discover, Fix "Ditters" on 40 Meters

10/29/2008

Silent since the summer of 2000, "ditters" have been heard once again on 40 meters by hams in North Carolina. According to ARRL Field and Regulatory Correspondent Chuck Skolaut, K0BOG, hams in that state contacted him on October 22 complaining of hearing a continuous string of "dits" on 7.0574 MHz. "We informed the FCC HFDFing station of the situation and asked if they could locate the approximate area of the 'dits' so we could get this resolved as soon as possible," Skolaut said. "They responded promptly and said it was coming from Westerville, a town just north of Columbus, Ohio."

Once the general location had been pinpointed, Skolaut called on ARRL Ohio Section Official Observer Coordinator Rick Swain, KK8O for assistance. Swain immediately alerted his team of Official Observers (OO) to check out the situation. "Neither I nor the OOs could hear the transmitter," Swain said in his report. "In a telephone conversation with one of the OOs near the target area, he suddenly stated that he could hear it, but that the signal was at the noise level, about S2 to S3. At just about the same time, I could hear it as well at my location [about 50 miles from the target area] -- just above the noise level -- for about five or ten seconds, then it disappeared."

Swain also placed a call to Assistant Section Manager Bill Carpenter, AA8EY. "Bill lives within the target area. I briefed him on the situation and he went right to his station," Swain said. "Bill checked the frequency and told me he was hearing [the 'dits'] at about S9. He said he thought he might know who it could be and that would make some calls."

Around 7:30 AM on October 23, Swain checked the frequency and found no signal. "I assumed that either Bill had found the transmitter or the owner came home, found it transmitting and turned it off," he said. "Later that morning, Bill sent me an e-mail saying that the signal was back on and about S7. I called Bill's house and left a message telling him I was on my way to Westerville to track down the signal. If he wanted to ride along with me while I looked for it, he was more than welcome to come." Skolaut said the signal was also heard in Newington that day.

When Swain arrived in Westerville, he had a list of the names and addresses of 172 licensees in the area, as well as a general idea of where the signal should be, based on the data from the FCC's HFDFing station. He also had his HF radio, an all-band screwdriver antenna, a GPS receiver and a VHF radio for information and directions.

"I drove around the area checking the signal and noted that it was about S9 and climbing," Swain said. He and Carpenter met up and continued the search together. About 15 minutes later -- with Swain driving and Carpenter giving directions -- "we noted that the signal was 30 over S9 and Bill had me make a left turn at the next street, saying that there was an address on the list we should check out. We stopped at that address, but no luck."

Swain said he then injected 30dB of attenuation and continued to drive in the same direction: "The signal was now reading 20 dB over S9 with the attenuator still on. We turned down the next street and the signal rose another 20 dB. I pulled into a parking lot and made a 360-degree turn as to determine the signal's direction. The turn indicated that we should proceed to a newly constructed housing area adjacent to the parking lot."

Swain and Carpenter then made their way over to the housing development and found that signal peaked. "Bill checked the list and found a ham lived on the street we were on, so we stopped and knocked on the door, but no one answered," Swain said. "We checked out the backyard and saw a 4-band trapped vertical antenna. We went next door and spoke to the neighbor and told him who we were and what we were trying to do."

With help from the neighbor, Swain contacted the ham at work and explained the situation. The ham told the neighbor how to get in the house and where they would find the transmitter. "We went in, found the transmitter in operation and turned it off," Swain said. "I noticed the ham had a large cat lounging near the transmitter and assumed the cat could have leaned up against the keyer paddle and started the transmitter. No other explanation could be possible without the owner hearing the transmit relay clicking."

When Swain and Carpenter left the house, they listened to the receiver and discovered the signal had disappeared.

"This was a great example of coordinated cooperation by the FCC and OOs to resolve a problem in a timely fashion," Skolaut said. "The DFing station told us that hopefully the OOs could handle it as the FCC District Office was unable to work the case at this time."

Calling this a "splendid example of cooperation," ARRL Great Lakes Division Director Jim Weaver, K8JE, echoed Skolaut's praise: "I believe the response to the situation was as fine an example of symbiotic relationship between member-staff-FCC-staff-field organization as one might find. Extremely well done by all hands."



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