Fw: FCC Seizes Radio Equipment

A. Joseph Ross joe@attorneyross.com
Fri May 27 16:52:48 EDT 2011

On 5/27/2011 4:09 PM, Dan.Strassberg wrote:

> That's true, but... The local oscillator (LO) of a superheterodyne FM
> receiver oscillates at the frequency to which the receiver is tuned
> plus the receiver's IF frequency (by law, 10.7 MHz). For example, one
> of the reasons why WCRB can't move very close to downtown Boston is
> that WERS on 88.9 transmits from One Financial Center downtown. 88.9 +
> 10.7 = 99.6, which is only 100 kHz from 99.5. Without a filter ahead
> of the receiver's demodulator, a signal at 99.6 + 10.7 = 110.3 MHz
> could be received by a receiver tuned to 88.9, but radiation from the
> LO itself is centered at 99.6 MHz and if the LO signal radiates, it
> can interfere with WCRB's signal at 99.5. Radiation from the LO of FM
> receivers tuned to stations in the upper half (approximately) of the
> FM band has the potential of interfering with aircraft communications.

So, if the pirate was shut down because it interfered with aircraft 
communications, what is to prevent legitimate stations from doing likewise.

A. Joseph Ross, J.D.             617.367.0468
92 State Street, Suite 700       Fax: 617.507.7856
Boston, MA 02109-2004          http://www.attorneyross.com

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