One benefit of owning an HD Radio in the United States is that all HD signals display a digital ID. Most stations broadcast their callsign assigned to them by the FCC, i.e. “WKYS,” while others broadcast their name, such as “STAR-FM.” Regardless of if a station chooses to show their callsign or name, they are limited to four characters and an optional suffix of “-FM” at the end (the latter having no bearing on if the actual station’s callsign legally has “-FM” in it, or not). Now it seems there is a new type of digital callsign appearing on stations that cannot be displayed on older HD radios, such as the Sony XDR-F1HD.
The Sony XDR-F1HD and its sister radios (the XDR-S10HDiP and XDR-S3HD) are among the first generation of HD Radios that debuted in 2008. The radios would always quickly identify all HD Radio callsigns once an IBOC signal was found, regardless of if it was “WKYS” or “STAR-FM.”
Local 96.3 WHUR Washington, DC’s HD Radio signal was on and off-air sporadically in the first few months of 2019. Their analog signal was also off-air at times, too. Because of this, I assumed the station was upgrading their equipment. Before 2019, the station had a digital callsign of “WHUR-FM” on all HD Radios, as seen in the screenshot to the left below. For a brief period in April 2019, the broadcasted callsign was simply “HD,” as seen to the right below. Both callsigns were easily read and displayed by the Sony XDR radios.
Much to my surprise, during a dial scan on the Sony XDR-S10HDiP on May 18, I found the station was not broadcasting any digital callsign at all. The XDR-S3HD and XDR-F1HD radios also didn’t show any callsign on WHUR.
In my 20 years of DXing (11 of them having HD Radio capabilities), I have never seen a station simply not have a callsign displayed when their digital signal was tuned in. Puzzled, I got out my other HD Radios (the Insignia NS-HD01 and Insignia NS-HDRAD2) and found that they were, indeed, displaying a digital callsign from WHUR, albeit with a new suffix at the end I had never seen before: “WHUR HD.”
The next day, I tuned in WHUR on my parent’s 2016-model car that has HD Radio, and found it could also “see” the updated “WHUR HD” callsign.
Another HD-capable radio I own, the Sangean HDR-14, can only display four characters in its digital callsign area and it doesn’t display the “-FM” suffix on participating stations. This is a limitation of the radio itself, and the “HD1+!” seen on the screen below is not part of the callsign and is instead a function of the radio–it appears on all HD Radio signals, regardless if they have the “-FM” in their displayed callsign or not. Even with the built-in limitations, the radio still displays the first four characters of WHUR’s updated “WHUR HD” callsign, as seen below. It doesn’t show a blank callsign like the Sony XDR radios do.
I think one of two scenarios are likely, given the developments with WHUR’s new callsign:
- HD Radio technology now allows a third “HD” suffix at the end of callsigns. A station can pick “WKYS,” “WKYS-FM,” or “WKYS HD.”
- Instead of being limited to four characters with an optional suffix at the end, HD Radio stations can now utilize the full seven characters to display any text of their liking. This means a station could theoretically display “Hot1025” or “Country” as their HD callsign. In this scenario, WHUR simply chose “HD” at the end of a fully-customized seven character string.
As for why the Sony XDR-series radios cannot see the new WHUR callsign, I am leaning toward option #2 being what is in play at the moment. Since there are differences in suffixes already between HD Radio signals and all radios simply display whatever the station chose, I would assume that any HD radio would be able to show “HD” as a suffix if that was the case. The technology is already there to account for differences in suffixes. In that instance, the Sony XDR radios should display “WHUR HD” without a problem.
Option #2, which affords changing the HD Radio data standard to allow for seven character callsigns, however, may cause a problem with older first-generation HD radios like the Sony XDRs. My other HD Radios were manufactured 2012-2018, so they likely have newer technology under the hood that would be compatible with future upgrades in the HD Radio standard, such as allowing for longer digital callsigns. Under this theory, since the Sony XDR radios are too old, they don’t “understand” the longer callsign being broadcast and, therefore, can’t display them, resulting in a blank on-screen display.
If my suspicions regarding option #2 are correct, then this would be a blow to the DXing community, since it means that if a station upgrades to the latest HD Radio technology, then there’s a chance that those with older HD Radios won’t be able to see any callsign upon a successful decode. The potential of any digital radio simply not displaying a callsign due to an incompatibility in technology when other equipment could is a disappointment and it may mean a DXer could miss an otherwise slam dunk ID.
Hopefully, this is just an isolated issue with WHUR’s HD Radio signal, and not a sign of things to come nationwide.
FM Radio DX 