Squawk Channel Tutorial

IMPORTANT UPDATE

posted Saturday, January 26, 2008

The NPR News Advisory (Squawk) Channel is moving from B77.0 to B78.9.

Please review this document to ensure continuity of service.

The new Squawk Channel will appear on B78.9 as of Monday, February 11 at 0900ET.

The old Squawk Channel will remain on B77.0 for one week after that until Monday, February 18 at 0900ET.

The Squawk Channel will run in parallel on both frequencies for one week to allow stations ample time to make the switch.

These Squawk Channel services will move from B77.0 to B78.9:

• News advisory audio from NPR producers

• SquawkNET automation tones

• National EAS messages

• Continuity chirps at the top and bottom of each hour

• Weekly EAS tests every Tuesday at 1315

The Breaking News Channel audio that is currently delivered on the right channel of B77.0 will NOT move to B78.9.
The old frequency is dual channel mono.
The new frequency is single channel mono.
Stations must subscribe to “NPR Special Events Coverage/Breaking News” in ContentDepot in order to receive Breaking News audio.

The new Squawk Channel frequency is on the same transponder, so no change is required to the PRSS downconverter. The new channel is a narrow band mono channel. The Comstream ABR-700 will adjust itself automatically to the new channel parameters. The mono audio will appear on both left and right audio outputs of the receiver.

An ABR-700 tuned now to B77.0 will show 256000 BPS in the display window.
When tuned to the new frequency of B78.9, the ABR-700 will show 64000 BPS in the display window.
This is normal.
The service is changing from dual mono at 128K (i.e. 256K) to single mono at 64K.

We will update this EUonline page as developments occur.

The NPR Operations Advisory Channel (known as the "Squawk Channel") is designed to deliver important news advisories and other timely information to stations carrying NPR News. It allows producers to instantly communicate information (by voice) about what is coming up with breaking news and live event coverage, including changes in program format, and start and end times.

A timechirp can be heard at the top and bottom of every hour as a continuity check.

In addition, National Level alerts and EAS Required Weekly Tests are provided for stations wanting to use the Squawk Channel for Emergency Alert Notification.

As of May 2002, additional signalling services, called SquawkNET are available. SquawkNET services use a specially configured DTMF decoder.

Although the Squawk Channel is uplinked by NPR's NOC, it is administered by NPR Master Control, and used primarily by NPR Operations. Call NPR Master Control (800-344-3890) with your technical questions.

UNTIL Monday, February 18 at 0900ET

DIGITAL: B77.0, LEFT CHANNEL. You can repurpose your ABR-700 for receiving the digital the Squawk Channel messages and tones on the Left Channel.
                                   RIGHT CHANNEL You can receive the Breaking News audio Stream on the Right Channel.

TROUBLESHOOTING, courtesy of NPR Distribution's Ralph Woods:
If your demod is authorized at all, your should get the channel.

If you're seeing "NOT AUTHORIZED" in the display window on the demod, you should call the Depot (202-513-2650) or the NOC to get the demod authorized.

Are you sure you've got the demod looking at transponder 3 ("B")?
You ~did~ leave one of the L-Band-to-70-MHz downconverters in place, right?
If you're not on transponder 3, the demod window would display "unusable" and "acquiring" and the bit rate numbers will cycle between 64000 bps, 128000 bps, 192000 bps, and 256000 bps.

If the signal level is too low, you would see "marginal" in the window.

The original concept of the Squawk Channel was to economically provide a direct audio path from NPR to member stations. When the transition to digital satellite transmissions was made, many stations had at least four analog demods on their shelf that were no longer usable---until the Squawk Channel was commissioned.
Those old analog demods can be reused for little or no cost to give stations a real-time, highly useful service.

In November 2006, the ContentDepot parallel operations began, using the new streaming decoders and new storage receiver provided by PRSS. Because these new devices replace a station's existing ABR-700 digital demods, those old demods could be put to use to receive the Squawk Channel on a digital satellite frequency.
Because the digital Squawk Channel is 256kbps/L2/Dual Mono, the Squawk Channel time chirps, announcements, and SquawkNet signalling is on the LEFT CHANNEL OUTPUT of the demod.

The right channel of B77.0 carries audio from NPR’s Breaking News Stream.
This is a holdover from the days before Content Depot.
NPR plans to discontinue this right channel feed in 2008 —exact date TBD.
This right channel feed does not replace the Breaking News Stream in Content Depot and should not be used as such.

To hear News Advisory audio without hearing the Breaking News Stream it is necessary to pull audio from the left side only. If you pull both left and right, or sum them together, you will hear Breaking News program audio and News Advisory audio simultaneously.

Under no circumstances should the left channel of B77.0 be routed to air. Doing so will put News Advisory audio on the air, which is not authorized under any circumstances. Stations that currently route the right channel to air should make arrangements immediately to receive Breaking News audio via a Content Depot streaming decoder port.

National Level Emergency Action Notifications Are Now Distributed Via NPR News Squawk Channel (Digital B77.0)

by Mike Starling, VP Engineering, NPR
(released April 26, 2000, revised September 25, 2000)

Background - EAS Rules Revisions The FCC's revision of the Emergency Alerting System (EAS) in 1994 added multiple conduits for distribution of emergency broadcast messages. Current generation EAS receivers have several inputs for tuning to the local EAS primary station (Local Primary or LP-1) as well as National Weather Service (NWS) broadcasts as well as additional EAS conduits. This expansion in input sources and the addressibility of EAS equipment have increased the reliability and relevance of EAS messages.

National level Emergency Action Notifications The national level alert function of the Emergency Alerting System is administered by the Federal Emergency Management Agency (FEMA). Over several decades, FEMA has provided equipment for distribution of national level alerts to over 30 AM clear channel stations nationwide, designated as Primary Entry Point stations (PEPs). PEP stations have hardened facilities with generators and, in some cases, tube-based program operating equipment for presumed immunity from an Electromagnetic Pulse event (EMP). EMPs are typically associated with detonation of a nuclear device in the upper atmosphere. With the waning threat of nuclear action directed against the United States, current scenarios focus on the most likely triggering event as a coordinated terrorist attack directed against the institutions of government.

During such an event, the government would operate from secure control points. Media access, at least initially, could be restricted to official information distributed through National level Emergency Action Notifications (EANs). National level EANs are only activated upon request of the White House. Broadcast network access to the PEP system has not been incorporated as part of the new EAS communications plan. However, the FCC's Emergency Alerting Advisory Committee, has been interested in establishing first level, reliable communications to a broader number of broadcast facilities, especially those in state capitals, to help facilitate communications to local governments in the event of disruption of essential federal functions.

Additionally, many NPR member stations operate in largely rural areas, in some instances in communities where reception of the designated primary CPCS station is spotty, at best. Most EAS CPCS stations are AM stations, whose signals have degraded due to increases in man-made interference and increased band congestion. Several stations have contacted NPR in the past asking whether NPR could provide a path for national level EAS alerts.

Industry Advisory Committee Request Members of the FCC's Emergency Alerting Systems Advisory Committee approached NPR in 1999 with a request to study the logistic feasibility and willingness to serve as a conduit for national level alerts.

• In agreement with the News Division, NPR Senior Management endorsed the concept for use of the "squawk channel" as a public service conduit for activation of the National level of the EAS. Naturally, this provides NPR and participating member stations with immediate access to important breaking news.

• Since no direct link to the PEP system is available, the CPCS stations in closest proximity to the PEP operating center, WBAL and co-owned WIYY in Baltimore, were identified as conduits for receipt of such messages. In January 2000 NPR established reliable reception of the WIYY signal using a dedicated rooftop yagi at 635 Massachusetts Ave. That signal feeds an EAS decoder, which has been inserted in the audio chain of the News Division's Squawk Channel . The decoder has been set to pass through all National level Emergency Action Notifications.
  
  
• In 2005, a hardened phone line connection was made to NPR, making NPR a PEP. An ENDEC EAS decoder, provided by FEMA, was installed as the final piece of equipment in the Squawk Channel audio chain.

NPR Master Control will transmit a closed circuit EAS TEST message each Tuesday at 1315ET i.e. 1:15PM Eastern Time (the former time satellite proof of performance measurements used to be scheduled for testing station demodulators). We will not transmit a Required Monthly Test, but continue sending the Required Weekly Test.
In addition, a SquawkNET TEST (Relay 3 activation) will be conducted following the EAS RWT.

Please contact NPR Engineering's Master Control at 800-344-3890 for needed assistance. Master Control Supervisor Rich Rarey (rrarey at npr.org ) has operational responsibility for this activity.

(note: The data burst generated by the TFT 911 Encoder will be heard through all monitors listening to the squawk channel. So as not to startle those monitoring the squawk channel thru hot speakers, we will make every attempt to make a voice announcement prior to the start of a test originating from NPR.)

The Squawk Channel's nominal level is +4dBu. Both the EAS signals and the SquawkNET DTMF signals are below +4dBu.

Please contact NPR Engineering's Master Control at 800-344-3890 for needed assistance.
Master Control Supervisor Rich Rarey (rrarey@npr.org) has operational responsibility for this activity.

We can give you an ad hoc audio test for continuity, or a RWT, or a SquawkNET test, at your request, schedule permitting.

NPR Master Control does not have the ability to directly transmit any other SquawkNET triggers other than TEST.

Interestingly, yes. Jerry Olson of Spokane Public Radio reports that his reception of the analog Squawk Channel is "... a great audible indicator of eminent loss of digital transmission whether due to solar transition or snow buildup in the downlink dish. You will get very audible noise from the squawk in plenty of time to get your boots on and scrape the dish. In fact, I've even used the AGC output of the demod to drive a meter that has trip points to activate a "snow alarm".

Additionally, in May 2002, a custom DTMF tone encoder service was added, called SquawkNET (see below).

What is SquawkNET?

SquawkNET is NPR's National Emergency Transmission system on the Squawk channel.

* SquawkNET Alerts stations when breaking coverage is imminent.
* It can automatically join NPR News when your station is unattended and important news breaks.
* The service is free for all NPR member stations (you must purchase and install the specified hardware)

If your station is operating unattended (automated) when important breaking news happens, SquawkNET can switch your station's programming to join NPR News for the duration of the breaking news programming.

SquawkNET is designed to rejoin your station's regular programming if the breaking news is over before your staffers reach the station. SquawkNET will also assist staffed stations via audible or visual alarms when breaking coverage is imminent.

Breaking news is news important enough to cause NPR to break format and offer continuous coverage on NPR News channel A66.5.

SquawkNET uses time-proven DTMF signals to trigger properly configured equipment at your station via the News Advisory Channel ( aka, the "Squawk" channel). The system has been successfully tested with several dozen NPR member stations.

All that's needed to use SquawkNET is a specially configured Dual Tone Multiple Function (DTMF) decoder from Conex Electro-Systems, Inc. connected to your Squawk Channel demod, and associated interface wiring provided by your engineering staff.
Stations already receiving the News Advisory Channel will have total hardware costs of approximately $300, plus a few hours of engineering labor and testing.

SquawkNET is an interim system, and an updated version of SquawkNET will be integrated into the next generation Public Radio Satellite System as it becomes operational in the next few years.

SquawkNET is a service of NPR's News division. If you have questions contact NPR Master Control Supervisor, Rich Rarey, (rrarey at npr.org) at 202-513-2577.

NPR will utilize a sequence of DTMF tones to provide four functions.
Three of the functions have been defined for specific purposes, the remaining function is for receiving a weekly test from NPR.

The four functions are as follows:

1. Relay 1, Automation Stop/Join NPR. To trigger your automation system, or other device of yours, to join NPR network audio on The Breaking News Channel stream for a special broadcast.

2. Relay 2, NPR End/Automation Start. To trigger your automation system, or other device of yours, to drop NPR network audio and restart your regular programming.

3. Relay 3, Future (System Test). This is a trigger for NPR Master Control to test your installation, and for a weekly "exercise" of the SquawkNET system.

4. Relay 4, Net Alert. To trigger an alarm of your choosing to notify you when a special, super-important announcement from NPR News is about to be sent down the Squawk Channel.
Routine announcements are not signalled.

In order to participate in this system your station will need to purchase a CONEX DT-40-NPR-1. This version of the DT-40 reserves relays 1-4 for NPR proprietary signaling.

Each relay when activated will provide a 0.25 second momentary action.The relay can be used in either the N.O. (normally open) or N.C. (normally closed) configuration depending on your station's specific needs. The DT-40-NPR cannot be configured to latch the relays.

The input of the CONEX DT-40-NPR-1 is connected directly to the audio output of the Squawk Channel receiver. No special filtering or other devices are required for this system to work. The tones are sent on the Squawk channel and are thus not heard on the air. The tones are set to be always present on the Squawk channel regardless of anything else happening on the Squawk channel, with the exception of EAS National Emergency Alerts.
EAS National Alerts will have priority over all Squawk Channel signalling.

The tone level is set to -15 dbu and has been tested to work solidly to -20 dbu. The DT-40-NPR sensitivity is adjusted by a top-panel screwdriver trimpot.
The Squawk Channel's audio level is a nominal +4 dbu.
Click the illustration below to see it full size.

Additional Resources:

Conex DT-40-NPR-1 Manual (.pdf)

Addendum to DT-40 Manual (Word .doc)

Illustration showing DIP switch settings for DT-40-NPR-1 (.pdf)

NPR researched manufacturers that could produce a well-built, modestly priced, relatively secure DTMF decoder that uses the tones in a way that is hack-resistant. Our tests with the Conex DT-40-NPR-1 have been successfully repeated again and again, both on the bench, and in Squawk Channel tests with NPR member stations.

You can purchase directly from Conex Electro-Systems (http://conex-electro.com)
1602 Carolina Street
Bellingham, Washington 98226
1-800-645-1061
360-734-4323
FAX: 360-676-4822

...or you can order the decoder through your usual broadcast equipment supply vendors.

Be sure that you order model DT-40-NPR-1. It is a special production version of their model DT-40.
NOTE THAT MODEL DT-40 WILL NOT WORK WITH SquawkNET---YOU MUST USE MODEL DT-40-NPR-1.