Topband: 1940 kHz intermod

[James V Redding PE]

Call the owner/operator at

https://mrbi.net/

or more directly with a free cell phone call to:

*MRBI Headquarters*

40 Exchange Place, Suite 1010

New York, NY 10005
Tel: 212-966-1059
Fax: 212-625-2894
and let them know of your concerns. It is not a small business. . . They
own 39 stations.

Curious! You did not mention that the program content was in Mandarin or
Spanish.

CUL,

Jim/VEZ

On Wed, Apr 19, 2023 at 10:35 PM Eric Scace K3NA <eric at k3na.org> wrote:

> Hi Frank, everyone —
>
>    One does not need another person to be harmed by the intermod on 1940
> kHz
>
>    AM broadcast regulations include a very strict bandwidth mask for any
> form of radiated spurious signal more than ±75 kHz from the carrier
> frequency. At these power levels, such spurs must be less than -80 dB below
> the carrier (measured at a point about 10 wavelengths from the center of a
> directional array, usually in the main beam).
>
>    There are very specific measurement procedures to be followed for
> compliance. Every AM station is required to measure — and retain a report
> of compliance in their station transmitter logs — annually (no more than 14
> months between measurements). The measurement procedures require some care,
> a very good spectrum analyzer, and a calibrated antenna.
>
>    If the station is out of compliance, it has 10 days to return to
> compliance before notifying the FCC. If the problem cannot be repaired
> within 28 days, the station must obtain an STA to continue operations.
>
>    ===
>
>    Now, as to the identity of the stations. The FCC’s AM Query <
> https://www.fcc.gov/media/radio/am-query> webpage is invaluable for
> researching issues like this.
>
>    Rick identified one audible program as from WWRU. WWRU operates 10 kW
> daytime with a 2-tower directional array at 40° 49' 13.36" N  74° 04'
> 02.51” W. The tower registration numbers are 1040103 and 1242403. At night
> it runs 10 kW into a 4-tower array
>
>    A search of AM stations within 3 km reveals, as reported by others,
> WKDM on 1380 kHz. [Note: Be careful using AM Query’s “radius around a
> lat-long” search tool, as the input must be in NAD-27, not NAD-83
> coördinates.]
>
>    WKDM uses a 3-tower directional array (daytime) at the same
> coördinates, and a 4-tower directional pattern at night. Tower #1040103 is
> shared by both stations. That means a diplexer is employed to combine the
> signals into this tower — and would be the first place to look for
> generation of a mixing product.
>
>    ===
>
>    What to do?
>
>    Both stations run 10 kW or more. On that basis alone, the chief
> engineer of each station is required to be an employee of the station — not
> a contract engineer. (The same requirement applies to any AM station
> running a directional pattern.) That means the chief engineers will be easy
> to contact — just call the station’s main phone number. WKDM’s website is
> here <https://www.am1660.com/>, and info at am1680.com <mailto:
> info at am1680.com> is the general email address. +1-718-352-1660 is the
> phone number at their headquarters location.
>
>    If this is unsuccessful, one can escalate to the points of contact
> registered with the station license. In this case, a search of the FCC LMS
> database reveals both stations are owned by the same company and have the
> same points of contact:
> seank at mrbi.net <mailto:seank at mrbi.net> … and the legal representative is
> Mark Lipp at lipp at fhhlaw.com <mailto:lipp at fhhlaw.com>
>
>    If no satisfaction has been obtained, anyone can file a complaint with
> the FCC Enforcement Bureau explaining that these two stations are operating
> out of apparent compliance, with the support data and information about how
> the station management has been unresponsive. The Enforcement staff
> maintain contact numbers for each station to use in cases of emergency, and
> will follow up (as I have personally witnessed).
>
>    I hope this helps.
>
> — Eric K3NA
>
>
>
>
> > On Jan 6, 2023, at 18:03, Frank W3LPL <donovanf at starpower.net> wrote:
> >
> > Hi Fred,
> >
> > We've figured out the mystery, now we need to determine if anyone is
> > being harmed by the weak, intermittent intermod on 1940 kHz
> >
> > 73
> > Frank
> > W3LPL
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