PRSS to Make System Adjustments for Combined Carrier Initiative

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The final phase of the PRSS migration to a single satellite transponder begins in May. The following message outlines what actions the PRSS will perform, and when, on Monday, May 7, 2018, as well as what each and every station should do beforehand to avoid experiencing audio issues.

At 1:59:50 pm ET on May 7, 2018, the PRSS will re-transmit the updated Combined Carrier definitions to all station receivers. Currently, stations have the new Combined Carrier set as Carrier A and the Legacy Carriers as Carrier B.   The PRSS will set both the Carrier A and Carrier B definitions to the new Combined Carrier.   This process will remove the Legacy Carrier definitions.

** It is strongly recommended that stations check now to see if their receivers are pointed at the combined carrier, before we perform this operation on May 7. It will be much easier for us to assist you with any issues locking onto the new combined carrier if you contact us now rather than immediately following the May 7 maintenance, when we may be fielding numerous station calls. The PRSS has prepared a document, available at http://www.prss.org/sites/prss/files/documents/Equipment/Verifying%20Tuned%20Carrier.pdf, that can assist you with checking to see where your receivers are pointed.

At 2:59:10 pm ET, the PRSS will adjust our master NTP time clock.  We are aware that there is a split-second difference in time that could result in audio being upcut. To address this, we plan to make an adjustment to the NTP clock. For most stations, this action will occur unnoticed with no impact on their operations. However, we are aware that some stations may have previously made timing adjustments locally to compensate for the PRSS clock. If this is the case, you will need to set your clock back to its original setting. If you do not, you will be a quarter-second off of the PRSS clock.

To repeat: if your station did not make any local timing adjustments, you do not need to take any action and you should not notice any effects of this work. If, however, your station made timing adjustments, or you notice any audio issues following this procedure, you will need to reset your timing to its original position. If you need assistance with this, please call the PRSS Help Desk at 800.971.7677 or prsshelp@npr.org.

If your station experiences audio issues after the switch at 1:59 pm ET, you need to contact immediately the PRSS Help Desk at 800.971.7677 or prsshelp@npr.org and we will troubleshoot the problem.

 

Below is an FAQ prepared to assist stations with the carrier move.

 

The PRSS is continuing with its plans to combine all streams and files traffic on a combined carrier. In the process of doing so, we have received multiple questions from the station community. As a result, we have produced this FAQ with information you may find useful.

If you have any questions not covered below, please contact the PRSS Help Desk at 800.971.7677 or prsshelp@npr.org.

 

Question 1: Once the SFX4104s are transitioned to the Combined Carrier, will Carrier A and B both switch to the new channel or should we 'copy' Carrier A's settings to Carrier B?

PRSS:  After the push of the definitions on May 7th, both L-Band 1 and L-Band 2 frequencies for Carrier A and Carrier B will be the same.  Your receiver will be able to lock to the Combined Carrier on either Carrier A or Carrier B.

 

 

Question 2: I checked my Receivers and I noticed that it has locked to Carrier B. Is this an issue?

PRSS:  There is a chance that your receivers had a fade at some point and switched over to Carrier B. That is a normal function of the receiver. The action being performed on May 7th is the next step in the process of migrating all receivers to the Combined Carrier.   If your receiver is locked to Carrier B, it will automatically lock onto the Combined Carrier after we update the Carrier B definitions.   At that point, both Carrier A and Carrier B will have the same carrier definitions.

 

 

Question 3: My receiver has locked to L-Band 2 - Carrier B. I have tried to use the option "Lock to Preferred" but that does not seem to work. What am I doing wrong?

PRSS: You are not doing anything wrong. The "Lock to Preferred" button unfortunately does not do anything.  For information about how to force your receiver to lock to Carrier A, please call our Help Desk at 800.971.7677 or email PRSSHelp@npr.org for additional information.

 

 

Question 4:  When I look at my Pro Audio 4104 receiver, I see the Eb/No value is no longer there, what should I look at to determine my signal quality?

PRSS:  The move to DVBS-2 does not have an Eb/No value in these receivers. Stations should monitor both Signal Level Carrier to Noise (C/N).  You will not see values for Signal Quality or Eb/No when the receiver is locked onto the Combined Carrier.  Also, there will be a slight difference in the readings between the L-band 1 and L-band 2. This is normal.

 

 

Question 5:  When I am monitoring Carrier to Noise, what is a good value for my station?

PRSS: Your station location within the satellite footprint will have some influence on your ideal Carrier to Noise level.  At a minimum, PRSS would like stations to have at least a 6 dB margin over the receiver minimum of 5.5 dB. Your receiver could incur a fade if the Carrier to Noise falls to 5.5 dB or less. In general, this means that your receiver should have a C/N of 11.5 dB or greater. If you are below this, you should review your entire RF path to ensure for optimized signal. If you have questions about your signal level, please call our Help Desk at 800.971.7677 or email PRSSHelp@npr.org for additional information.

 

 

Question 6: Will the Legacy Carrier remain functional for a period of time and if so, when will it be decommissioned?  I use a pair of SR2000pro receivers for NPR programming and Breaking News and I'm just curious how long they'll remain useful.

PRSS: The Legacy Carrier will be shut down very soon.  You should be making arrangements to transition all programming over to your 4104 receivers.  This will ensure that your programming will continue uninterrupted on the Pro Audio 4104's.  After the Legacy Carrier has been shut down, stations will not be able to acquire programming from the SR2000 units. 

 

 

Question 7:  I have programming that I am airing that comes from a SR2000.  How do I check to see if I am getting this same programming on my Pro Audio 4104 receivers?

PRSS:  When you log into ContentDepot, look for the menu option in the upper right called: Live Receiver Schedule. When you click on this, you will see a grid showing your station's receivers. You will see the Live programs that are assigned to each audio port of the receiver. This helps you understand what programs you are currently subscribed to and which receiver and which port the program is assigned to. If you do not see the program in question, you should search for it and subscribe using an open available port.

 

 

Question 8:  What happens to stations that do not migrate their programming away from the Legacy Carrier via a SR2000 to a subscription within ContentDepot on their pro Audio 4104 receiver?

PRSS: To maintain audio programming of Live streams, stations must subscribe to those programs within ContentDepot.  When PRSS shuts off the Legacy Carrier, the station will lose all audio programming from the SR2000. 

 

 

Question 9:  Our receivers have all of their ports in use. Can I assign more than one program to a port?

PRSS:  You should not assign more than one program to a port. If you schedule two programs that air at the same time to the same port, ContentDepot will flag this as a conflict. You should only assign one concurrent program to a port at a time. 

 

 

Question 10:  Our receivers have all of their ports in use. Can we purchase additional receivers if necessary?

PRSS: Yes, please call our Help Desk at 800.971.7677 or email PRSSHelp@npr.org for additional information.

 

 

Question 11:  What about the Squawk channel? How should my station get Squawk updates?

PRSS: Squawk is currently available through several sources.

.             Stations can subscribe to Squawk via ContentDepot and have the Squawk channel assigned to an available port on their Pro Audio 4104 receivers.

.             Stations can retune a SR2000 unit to the dedicated Squawk carrier on Transponder 1.

.             Stations will also be able to pull in the Squawk channel via the Legacy carrier up until the carrier is shut off.

.             Stations can also listen to Squawk via the webstream at http://npr.org/squawk , as a backup to the above sources.

 

 

Question 12:  Will the weekly test of the Emergency Alert Notification still be available on the sources listed above?

PRSS: Yes. The required weekly test that is performed each Tuesday at 1:15 pm ET will be heard on all sources listed above.

 

 

Question 13: When I subscribed to the Squawk program via ContentDepot, I see that on my receiver that it is listed as Stream 20, is this correct?

PRSS: Yes, if you are looking at the subscription port of a Pro Audio 4104, Squawk will appear as Stream 20. PRSS has moved Squawk to Stream 20 in anticipation of both the Future System that is in development and the loss of the Legacy Streams carrier on Transponder 3. 

 

 

Question 14:  I saw that there is a dedicated carrier for Squawk and I retuned our SR2000 to pull in that channel. I cannot find other programs however like Classical 24 or the BBC. What did I do wrong?

PRSS: The dedicated carrier for Squawk only has Squawk audio. No other programming is available via this dedicated carrier. Please also note that there are no relays or NTP syncs associated with the dedicated carrier for Squawk. This channel only has Squawk audio. 

 

 

Question 15:  How long will the dedicated carrier for Squawk remain available?

PRSS:  The current plan is to keep the dedicated carrier for Squawk up until mid-2019.  There are several dependencies that can affect this date including the Future System and needs for transponder space.

 

 

Question 16:  Where can I find out more information about the Combined Carrier transition?

PRSS: The PRSS held a webinar earlier this year to discuss the transition to a combined carrier. The webinar provided a timeline for the transition to a single transponder and the Combined Carrier and also involved an extended discussion on the current and future status of the Squawk Channel. Following the presentation, there was a Q&A session between participants and the PRSS.

Part of the discussion revolved around a guide prepared by the PRSS engineering team on setting a SR2000 receiver to the new SCPC Squawk Channel. To view a copy of this guide, please visit this link: http://prss.org/sites/prss/files/media/customer-support/Squawk%20SCPC%20Guide.pdf

An archived copy of the webinar presentation, including the Q&A between the PRSS and stations, is available here: http://prss.org/sites/prss/files/media/video/2018-02-06%2014.02%20Live%20Streams%20Transition%20to%20Combined%20Carrier.mp4.

A PDF of the PowerPoint slides, without audio, is available at http://www.prss.org/sites/prss/files/content-images/customer-support/Combined%20Carrier%2002.06.18.pdf.

 

Question 17:   I have checked my receiver, it's locked onto the Combined Carrier, I have good signal and I have updated my subscriptions so everything is now being received by the Pro Audio 4104, is there anything else I need to do?

PRSS: Wow! Give yourself a pat on the back. Your station is ready!

 

Posted: May 1, 2018