[A-DX] SWRG#99 "2:43 Mysterious radio signal disabled key fobs"

Fr Mai 10 02:09:38 CEST 2019

Welcome to program 99 of Shortwave Radiogram

I'm Kim Andrew Elliott in Arlington, Virginia USA.

Here is the lineup for today's program, in MFSK modes as noted:

  1:35  MFSK32: Program preview (now)
  2:43  Mysterious radio signal disabled key fobs
  6:05  MFSK64: ASCII art
  6:48  Some trucks in Germany now using overhead power lines*
10:26  This week's images*
28:35  MFSK32: Closing announcements

* with image(s)

Please send reception reports to 

Twitter: @SWRadiogram

 From ARRL.org:

Hams Help Trace "Mystery" Signal Disrupting Keyless Entry Devices
in Ohio

7 May 2019

A recent article in The New York Times reported that many garage
door openers and keyless vehicle entry fobs in an Ohio town near
Cleveland mysteriously stopped working. While the article invoked
The X-Files and hinted initially that a NASA research center
somehow could be involved, the cause was not so much mystifying
as arcane.

"Garage door repair people, local ham radio enthusiasts, and
other volunteer investigators descended on the neighborhood with
various meters," the May 4 article by Heather Murphy recounted.
"Everyone agreed that something powerful was interfering with the
radio frequency that many fobs rely on, but no one could identify
the source."

More than a dozen residents reported intermittent issues getting
their key fobs and garage door openers to operate, and most lived
within a few blocks of each other. At one point, the local power
utility started shutting off power to areas where the strongest
RF signal was detected, but the signal persisted. Dan
Dalessandro, WB8ZQH, a TV repairer, was among several hams who
investigated. He initially picked up "little blips" on a signal
detector, but finally, on one block and at a particular house,
the signal was quite loud.

"The source of the problem was a homebrew, battery-operated
device designed by a local resident to alert him if someone was
upstairs when he was working in his basement," the Times
reported. "It did so by turning off a light." The individual,
who, the article said, has special needs, was not identified for
privacy concerns. The inventor, who had no malicious intent, had
no inkling that his device was wreaking havoc on the neighborhood
until a North Olmstead City Council member and a volunteer
knocked on his door. The device operated on 315 MHz, the
frequency many keyless-entry devices use under FCC Part 15 rules.
The device’s battery was removed, the signal stopped, and all who
were involved breathed sighs of relief.


Shortwave Radiogram now changes to MFSK64