WDER-AM 1320 DA Out Of Tolerance CLARIFICATION

[Dave Doherty]

FCC Rule 73.1680(b)(1) gives AM licensees emergency authority to operate at 25% of authorized power with a variety of antenna arrangements, including a single tower of a DA. Within 24 hours after starting the operation, the licensee must make "an informal letter request" to the FCC, after which the FCC can specify a lower power, different antenna arrangement, etc.  The STA route is usually used, but the rule does not require it. This may be why you see only some temporary operations as STAs in CDBS.

I've seen directional stations operate for months ND at 25% power.  If the FCC gets interference complaints, they can order the station to reduce power, but the general condition of the AM band, particularly at night, is such that interference from these operations often causes no interference that can be tracked back to the source.

-d


Dave Doherty
Skywaves Consulting LLC
PO Box 4
Millbury, MA 01527-0004
401-354-2400
202-370-6357 (DC)
650-479-2881 (fax)




-----Original Message-----
From: boston-radio-interest-bounces@tsornin.BostonRadio.org [mailto:boston-radio-interest-bounces@tsornin.BostonRadio.org] On Behalf Of Dan.Strassberg
Sent: Sunday, January 20, 2013 3:00 PM
To: Laurence Glavin; boston-radio-interest@lists.BostonRadio.org
Subject: Re: WDER-AM 1320 DA Out Of Tolerance CLARIFICATION


I was not aware that WAZN ran 800W ND while it was installing its DA-2 setup at 75 Concord Ave in Lexington, but if that was the case, 800W ND is equivalent to more than three times the equivalent nondirectional power that WAZN's 1400W daytime directional pattern effectively sends at 180 degrees (that is, in the direction of first-adjacent WSAR). Using that same pattern and power, WAZN sends the equivalent of more than 10 kW ND to the northwest during the daytime (323 degrees, the radiation maximum). The night-pattern maximum (to the southeast; 323 degrees), using 3400W is equivalent to ~25 kW ND. Anyhow, WAZN provides a second example of STA parameters that exceed signal strengths that either are licensed or are permitted via CP. Put another way, the FCC apparently sometimes grants stations STAs that do not fully protect the licensed operation of other stations.

-----
Dan Strassberg (dan.strassberg@att.net)
eFax 1-707-215-6367

----- Original Message -----
From: "Laurence Glavin" <lglavin@mail.com>
To: "Laurence Glavin" <lglavin@mail.com>; <boston-radio-interest@lists.BostonRadio.org>
Sent: Friday, January 18, 2013 1:01 PM
Subject: Re: WDER-AM 1320 DA Out Of Tolerance CLARIFICATION


> >----- Original Message -----
>>From: Laurence Glavin
>>Sent: 01/10/13 04:46 PM
>>To: boston-radio-interest@lists.BostonRadio.org
>>Subject: WDER-AM 1320 DA Out Of Tolerance; Running NDA Temporarily
>
> This wouldn't be extraordionary except for thr idea that a station would
> have much
> higher power with an STA toward protected stations than when running its
> authorized facilities. If I recall correctly,
> WAZN-AM 1470 ran 800 watts NDA out of Lexington while its pattern was
> being installed on the towers for
> WWDJ-AM 1150, viewable on Scott's Tower Calendar this year. It seemed to
> come in where I live with the
> same signal then as it does now.