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Nineiron
12th May 2006, 11:40
Mass by radio is deemed aircraft hazard
From:The Irish Independent
Tuesday, 9th May, 2006
ON a wing and prayer took on a whole new meaning after it emerged that
aircraft might be tuning into more than air traffic control.
Hundreds of house-bound parishioners across the country have been tuning
into radio broadcasts of daily and Sunday Mass from their local churches.
But it was discovered that the unlicenced transmitters involved might be
interfering with radio frequencies on passing aircraft and they have
been forced to shut down.
The communications regulator ComReg said it hoped to have a dedicated
radio frequency in place later this year "to meet the needs of religious
and other community organisations".
Last night, the Catholic Communications Office said the Church did not
condone illegal broadcasts but said the relaying of Mass was a lifeline
for those in hospitals, hospices and parishioners unable to attend church.
Director of communications Martin Long said they hoped to discuss with
the regulator ways of re-establishing the broadcasts as soon as possible.
The Irish Aviation Authority told the Irish Independent that for the
past year it had been receiving complaints of frequency interference
from aircrews overflying Ireland.
"We identified a trend that most of the interference seemed to be
happening at morning time and have been working with ComReg to get to
the bottom of it," said an IAA spokesperson.
"As a result of its inquiries ComReg has contacted three churches in
counties Kildare, Meath and Kilkenny in relation to the transmission of
religious services."
The regulator said it fully understood the importance of such local
community services and intends to permit wireless public address systems
to meet the needs of the housebound "be they sick, disabled, and or
elderly".
ComReg said it intended setting facilitating such public address systems
on the 27.6-27.99 MHz band later this year.
Fr Brendan Quinlan, PP of Ballygall Road, Finglas in Dublin said they
had transmitted a Mass daily and on Sundays to the housebound in the parish.
"I knew it was sort of a grey area but I didn't know that we were
breaking the law, not only in transmitting mass but in having this
equipment because we have no licence to transmit."

bubbers44
12th May 2006, 12:13
I was a technician working on business radio equipment and had to do a lot of investigating on radio interference. Especially on mountain top repeaters where transmitters are close to each other you can get some interesting harmonic interference where for instance doubling one frequency and subtracting another will cause a third frequency to emit. One time a simple marine weather receiver was sending out a harmonic of the oscillator which interfered with another businesses receivers. At Orange County airport I found a high speed printer at our airline that was interfering with clearance delivery out 20 miles. Unauthorized radio transmissions are a major problem.

Nineiron
12th May 2006, 20:40
They must be using old CB equipment, possibly American. Interference coming from blocking or overmodulation. But its a strange frequency allocation offered. The CB band is 40 channels, 10Khz spacing, between 26.965 and 27.405, carefully chosen so that harmonics do not arrive on ILS/LOC freqencies.
I like the assumption from the man of the cloth that this was a 'grey area'