fcc – Page 11 – Engineering Radio

Ready for CAP? (AKA Common Alert Protocol)

Like any good government agency, the FCC in conjunction with FEMA is working on upgrading the acronym-heavy EAS system with CAP, which stands for Common Alert Protocol. CAP includes something that FEMA has been working on something called IPAWS, which stands for Integrated Public Alert Warning System.

The FCC is still in the comment/response process (FCC Docket 04-296) which can get long and drawn out. I would not expect to see any NPRM until late fall 2010 with any changes taking effect in early 2011 or so.

Basically, CAP looks like this:

An EAS to CAP converter monitors a CAP source (think e-mail server) and when a CAP message is received, it converts it to EAS protocol and sends it to an input source of an EAS encoder/decoder. The EAS encoder/decoder then passes that information through and broadcasts it. Of course, the EAS encoder/decoder can still be programmed to pass through specific types of messages for specific areas and ignore all others.

Thus far, several manufacturers have designed CAP converters for use with existing EAS units:

TFT, Inc model 2008 CAP to EAS converter
SAGE Alerting Systems ENDEC
Gorman Redlich CAP to EAS decoder system
Digital Alert Systems DASDEC-II
Trilithic systems EAS plus

Implementation would look something like this:

For a TFT-2008 system. Others such as SAGE and Trilithic are integrated into the EAS encoder/decoder units. Basically, the CAP part of the EAS system needs an ethernet port with access to an IP gateway to receive messages from the CAP server located off site. That is the weak link in the system, as far as I am concerned.

It is not like some of our so-called trading partners have been trying to tinker with the inner tubes or anything. It is also not like that same trading partner makes most of the cheap ethernet switches and routers found in many radio stations, hardware that can be easily configured remotely. Configured to redirect certain IP addresses to new, exciting, and exotic locations such as Iran or Pakistan.

Perhaps I am paranoid, or not. It falls back to my time in the military when somebody said “It’s good to be a little paranoid if everyone is out to get you.”

Blanketing Interference and RFI

Blanketing interference refers to the phenomenon of receiving radio signals on devices not designed to do so. In broadcast radio, this is defined for AM stations in part 73.88 as:

The licensee of each broadcast station is required to satisfy all reasonable complaints of blanketing interference within the 1 V/m contour.

And for FM stations, it is part 73.318:

Areas adjacent to the transmitting antenna that receive a signal with a strength of 115 dBu (562 mV/m) or greater will be assumed to be blanketed.

Any interference to any device with that signal contour is blanketing interference. 73.318 further states that:

permittees or licensees who either (1) commence program tests, or (2) replace their antennas, or (3) request facilities modifications and are issued a new construction permit must satisfy all complaints of blanketing interference which are received by the station during a one year period.

I have always taken a more pragmatic approach to interference complaints. Rather than pass the buck and tell the homeowner or business owner that it is not our (the radio station’s) problem, I’d go and try to help them out. Generally speaking, the interference problems are close to the transmitter site, so on the next trip to that site, I would bring RFI filters and my 25 years of RF experience and solve the problem. I would like to think this helps the station’s and the company’s image in the community.

Most of the problems are pretty easily solved, although once in a while, I have come on some head-scratchers. An AM station playing on the outlets in a guy’s garage, the mic cords on a church PA system, and an off switch on a blender, off all things. The Bare Naked Ladies had a line in the song Light up my Yard: “we can dance to the radio station that plays in our teeth.”

What I have found is to start with the simple stuff first, check the ground on the electrical service entrance panel. One might be surprised to find it disconnected, corroded, or missing completely. On more than one occasion, I fixed all of the RFI problems with a simple turn of the screw holding the ground wire to the grounding electrode. In my experience, this is the most common single failure point. A disconnected ground will cause the entire neutral wiring system to act like a giant AM antenna, with all sorts of bad outcomes.

Most often, telephone answering machines, cordless phones, and other devices powered by wall warts are suspect. Those devices do not have a path to ground. A few turns of all the wires coming and going from said device around a ferrite core such as a snap on TDK RFI EMI filter available from Mouser will take care of it. Mouser has several different versions available.

Occasionally, one needs to put on a detective hat and do some footwork. Mast mount TV antenna preamps can cause untold heartache and problems. One such incident involved the second harmonic of an FM station falling exactly on channel 11’s audio frequency. This was affecting several houses in a one-block area. I finally found the problem at one of the complainant’s houses when I pulled the TV out and found the preamp power supply. Unplugging it made all the problems go away (I hate Radio Shack).

Usually, the process of elimination will discover the problem and thereby reveal a solution. The aforementioned church incident was discovered after I began unplugging microphone cords from the back of the Mackie mixer in the choir loft. It turns out several mic lines were plugged into the back of the mixer, unused and unterminated, creating a large long receiving antenna on the cable shield, which happened to be aligned perfectly to pick up RF from an AM station.

FCC authority to conduct warrentless searches of Private Property

I was this interesting tidbit on the Radio World website the other day. The question is, how much authority does the FCC have to conduct a search of a private residence? The Electronic Frontier Foundation wanted to know therefore they sent a FOIA request to the FCC seeking documents supporting this claimed authority.

The documents received seem to be redacted and some are mostly blank, such as the training module on how to obtain permission to enter private property is supposed to take 6 hours to complete, but consists of 3 paragraphs and 2 questions. Hopefully, that is redacted and does not reflect on the quality of agents the FCC is employing these days. The upshot seems to be the agent either needs a warrant or permission.

It may be surprising to some citizens, however, the FCC does have the authority to investigate radio signals, whether they are intentionally generated, as in a pirate broadcaster, or unintentionally generated, as in a piece of gear gone bad.

According to federal regulations, an FCC agent may request entry to inspect a private building anytime he/she believes there may be a device emitting radio frequency energy. This includes anything with an FCC part 15 sticker, which can be computers, TV remote controls, garage door openers, WiFi network routers, etc. This basically covers every house in the US as well as most businesses. Those rules were written when most homes and businesses did not have any RF generating devices and there was little to indicate that they ever would.

The consequence of failure to allow an FCC field agent into a residence or business appears to be the issuance of a citation in the form of a threatening letter. Continued intransigence would be met with a NAL (Notice of Apparent Liability) followed by a forfeiture notice also known as a fine. The typical FCC fine these days seems to be $10,000.00. If it is a repeated and willful violation, the equipment can be ceased and the perpetrator arrested.

In instances where the safety of life is in question, then every step necessary to disable the offending device needs to be taken. Things like transmitters spurring into aircraft frequencies or TV antenna amplifiers running wide open, also interfering with aircraft frequencies come to mind.

One of the examples given details a field agent trying to track down a noisy cable TV amplifier. From the FCC field agent’s perspective, the homeowner appears to be a royal pain in the ass. In this day and age when everything has a computer and most of them generate RF, tracking down interference can be a painstaking process, especially where housing is dense. Uncooperative homeowners, especially dumb ones, who have no idea what they have plugged in only make things worse.

Still, there is the issue of fourth amendment rights, which, if the above law was misinterpreted, misused, or applied with the wrong standard would likely be trampled. In these days of extra-constitutional activity, giving Los Federales entry into one’s house might invite unwanted scrutiny by other agencies. As far as changing the rules, with the current group of scoundrels and rouges in the legislative branch, one might end up with something ten times worse than before.

What is really wrong with EAS?

Aside from it hasn’t worked… Over the last several, the FCC has released no fewer than five proceedings regarding EAS. To date, few, if any meaningful changes have taken effect. The stated purpose of the Emergency Alert System (EAS) is to:

provide the communications capability to the President to address the American public during a national emergency.
may be used by state and local authorities to deliver important emergency information, such as AMBER alerts and weather information targeted to specific areas.

Seems pretty straightforward. Local weather emergencies would seem to be the most likely reason for EAS activation, followed by things like Amber Alerts, chemical spills, evacuations, etc. To meet those ends, the FCC mandates that radio (traditional and IBOC), television, cable, wireless cable, direct satellite TV, and satellite radio participate in some way or another. So far, it seems like a fair idea. Then comes the implementation, which is flawed. To start with, EAS still relies on a daisy chain relay system designed during the 1960s for CONELRAD. The over-the-air monitor assignments of other broadcast stations are the only mandatory information sources in the system. Other, more relative local sources such as the national weather service, local government, and so forth are optional. Next, the most used and most useful part of the EAS, local and state-level alerts are completely optional. Very little or no information is provided to local government agencies on how to access EAS in the event of an emergency. Then the issue becomes one of unmanned stations. The initial EAS message goes out over the airwaves, which takes about 2 minutes at most, then it’s back to the music. No amplifying information, check back for more information when it becomes available, etc. Nothing. It has occurred in several cases where a radio show is voice tracked, complete with a weather forecast, which is the opposite of real-time weather warnings. If one happens to miss the initial EAS broadcast because they were listening to another station or whatever, well, too bad. Finally, the National Weather Service itself over-activates. One line of summertime thunderstorms passing through the area can trigger 10 or even 20 EAS alerts. Over-activating, with the same digital tones (rrrrrrannk, rrrrrrank, rrrrrank) followed by the EBS tone than some computer-generated voice just gets annoying. To summarize:

The national EAS has never been tested, who knows if it will work
The EAS relies on unreliable over-the-air daisy chain relays for its mandatory monitor assignments
Local and State level EAS (including weather-related alerts, something that could be really useful) is optional
When connected to the NOAA weather radio system, the NWS overuses the EAS activations

Here is an idea: For at least ten years now, the idea of a CAP has been batted around. It seems like a good idea, let’s do that. Get rid of EAS, send emergency information to everyone’s cellphones or whatever, and stop fining broadcasters for missing a monthly test. The weak link in the EAS is the broadcaster’s themselves. History has shown (over and over again) that the current crop of radio station owners cannot be bothered to meet even the simplest of their public obligations. The FCC has shown it is only interested in collecting big fines for missed EAS tests, not actually making the system work. The system is broken. As terrestrial radio (and TV) goes terminal, the public will still need to receive emergency information, the CAP idea can fill this requirement. It is time to pull the plug on EAS once and for all.