Mannasas,Va COMTek to FCC: report no interference attributable to BPL.

Clearer air for Manassas hams
By JACLYN PITTS
jpitts@manassasjm.com
Wednesday, April 12, 2006


Clearer communication may be in the air for Manassas-area amateur radio operators.

Amateur radio enthusiasts have been battling alleged interference from broadband over power line technology in the city since the autumn of 2003, when Manassas first implemented the system.

Now Communication Technologies Inc. (COMTek) is updating its "grandfathered" equipment to the latest technology offered by BPL equipment supplier Main.Net.

COMTek spokesman Scott Stapf said the company has begun upgrading about 600 overhead lines.

Stapf said the company hopes to have upgraded all overhead lines by November.

By upgrading the equipment, any interference to shortwave radios should be eliminated, Stapf said.

But for many local amateur radio users, or hams, upgrading overhead lines isn't enough.

George Tarnovsky, vice president for Ole Virginia Hams, a local ham radio group, said he thinks COMTek has continually avoided addressing underground BPL lines.

Tarnovsky cited one of his own interference surveys on Hastings Drive and Wellington Road, where he's experienced interference he attributes to BPL.

Both of those areas are served by underground BPL lines, Tarnovsky said.

However, he said upgrading the above ground equipment will help.

Manassas became the first American municipality to implement the technology citywide in 2003.

By plugging a modem into any city electrical outlet, subscribers can get high-speed Internet access for about $29 per month, approximately half of what cable and DSL providers charge.

BPL radiates off power lines and can make certain shortwave radio frequencies inaudible.

COMTek's BPL service runs through the city's power grid and has nearly 1,000 subscribers.

The company's announcement rides on the heels of the Federal Communications Commission's request that Manassas and the company investigate interference allegations and take steps to eliminate interference.

COMTek sent its preliminary interference findings to the FCC on Thursday, which cited no interference attributable to BPL.

"The reality here is that the test results speak for themselves," Stapf said.

However, Stapf said the company will continue to test for interference.

Tarnovsky questioned the survey's findings.

The survey group tested for interference while the BPL system was in operation and when it was shut off.

But Tarnovsky thinks this "on/off" testing was done in spurts, so the full effects of interference wouldn't have been noticeable.

COMTek's equipment upgrade plan isn't the company's first attempt to eliminate potential interference.

The frequencies used by hams in Manassas have been "notched," or removed from use by BPL.

COMTek announced in January it had notched about 600 overhead BPL devices.

Tarnovsky is certain that ham radio interference is due to BPL.

Prior to the system's deployment in 2003, Tarnovsky said he and fellow amateur radio enthusiasts only experienced occasional interference from power lines, which was easily corrected.



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