RADIOACTIVITIES Newsletter of the Argonne Amateur Radio Club
Volume XLIII, Number 7	July, 2002

As reported in February 2001 http://www.arrl.org/news/stories/2001/02/14/3, certain amplified TV antennas have been found to produce interference in the 400-500 MHz range that could cause problems for Public Safety and Amateur Radio systems. Winegard has been replacing its offending Sensar antenna units at no cost. See the Winegard Web site http://www.winegard.com/products/mobile/sensar_customers.html for details.

The FCC’s Dave Galosky in the Office of Engineering and Technology says Winegard estimates there still may be thousands of defective units in the field. Boat and RV owners using these antennas may experience interference to onboard systems, such as GPS.

According to the FCC, similar antennas from three other manufacturers also produce interference. The RadioShack RS 1624 — made by TDP Electronics — transmits a spurious emission at 468 MHz and at its second harmonic, 936 MHz. The Shakespeare Seawatch 2050 antenna and an unspecified antenna model made by RCA/Thompson also have been reported to generate similar interference, the FCC says.

The restrictions resulted from a revised National Plan of Frequency Allocations put into place in March 2000 by the Public Services Regulatory Entity — Panama’s FCC. Enrique Preciado, HP1IBF, credited restoration of the bands to the tenacious efforts of the Radio Club of Panama (HP1RCP) and of many individual amateurs in the Central American nation.

Preciada said that after lengthy discussions, debates and public hearings, Panama’s amateurs convinced authorities to reconsider the value of amateur activity to the community — as well as the importance of having Panama’s regulations conform to international conventions and agreements that it had already signed. Only one was not restored to amateur use — 33 cm (902-028 MHz). The other bands restored included amateur allocations at 1.2 GHz and higher.

“We learned a lesson that we radio amateurs ought to use our space in the spectrum, care for and protect it very jealously, if we want our hobby to survive,” Preciado told ARRL. — Jon Siverling, WB3ERA/ARRL.

I hope one and all come out for the Evening Under The Stars program. It works out so nice with dinner and the program afterward it is something that is hard to miss. And Chuck and Ann work so hard putting it all together the more that attend the more fun had by all.

Chuck called the meeting to order but then had to adjourn it since we didn’t have a quorum.

We did have an informal discussion. Joe suggested that we consider a constitution change reducing the 5 member quorum requirement to 50% (4 of the 8 Board members) as many organizations do.

Joe stated that Dale was unable to attend today because he is out of town. He also reported that he had received about a dozen forms from full members signing up for the periodicals distribution lists.

He will forward the final lists to the routers on June 17. Chuck reported on Field Day preparations. He and Bruce are making arrangements for three Field Day volunteers who are not employees to come on-site for the event. Plans are in the works to check out the equipment before the event. There will be a GOTA (Get On The Air) station. This new ARRL designated station replaces the previous novice/technician station. We will be operating category 2A.

In January, the FCC wrote Cincinnati AM radio station WLW and Cinergy Corp — the electric utility serving the region — to help resolve the unusual and longstanding interference situation that was affecting local amateurs.

Apparently spurious signals associated with WLW transmissions had been monitored over a wide area and frequency range and were severely affecting some amateur bands.

The investigation focused on utility towers carrying 345-kV lines in the vicinity of the WLW broadcast tower. Jay Adrick, K8CJY — a member of the amateur team involved in tracking down the problem and one of those honored — explained at the Dayton ARRL Forum earlier in May that the primary problem seemed to stem from so-called static lines on the towers, which do not carry electrical power.

The static lines, he pointed out, were not sufficiently RF-bonded to the tower structure. “They’re actually loose-fitted,” he said. “At 60 Hz, it’s a reasonable ground.” But at RF, it acted as a non-linear junction, and the static wires acted as a huge antenna. The result was something that sounded a bit like a spark gap modulated by WLW’s audio on several amateur bands.

Success did not come easily, and mop-up operations continue. Hollingsworth called the situation “a history-making RF interference case” that generated more investigative analysis than any other case in his years with the FCC.

Ohio ARRL Section Manager Joe Phillips, K8QOE, said the local amateurs brought the matter to the FCC’s attention after working with WLW and Cinergy for almost two years to pin down the cause of the spurious signals.

Honored with certificates at the ARRL Forum in Dayton in addition to Adrick were team leader Bob Reiff, WA8ULW; Ted Homan, WB8WFG; Herb Nichols, W3EOA; Geoff Mendenhall, W8GNM; and Paul Jellison, WD8KMX.

Jellison is regional engineering manager of Clear Channel Communications which owns WLW. Also honored were non-amateurs Jeff Antoni and Kelly McMahan, both of Cinergy Corporation.

The certificates were signed by ARRL Great Lakes Division Director George Race, WB8BGY, and ARRL Lab Supervisor Ed Hare, W1RFI, who assisted in the efforts to resolve the interference situation. The amateurs were cited for “creating an example of longtime and continuing corporate-amateur radio cooperation in an interference abatement of high power RF signals.”

Though some interference remains, Phillips said, the local amateurs and both corporations discovered many possible sources of trouble and have established a working procedure for clearing them up.

“Saying the interference is all cleared up would be foolhardy given the complex nature of the engineering involved,” said Phillips, who recommended the awards, “but the two words that describe this historic work would be ‘patience works.’”

Under FCC Part 15 and Part 73 rules, incidental noise radiated by power company equipment or spurious emissions from a broadcast transmitter must be corrected if they cause harmful interference to radio communications.

A small voice at the back of the room rang out, “And there’s the teacher, she’s dead.”