Part 2 of 2

In the first installment of this article on the recent development of a “new breed” of Ch. 6 “Franken FM” TV/radio operations, several members of the ATSC 3.0 standards group voiced their opinions as to the validity and usefulness of these hybrid facilities that began popping up last year.

This time, we look at the engineering side of the “May/December” marriage of broadcasting that’s been around for such a short time that the “new” hasn’t even begun to wear off alongside one that’s existed for close to nine decades. This is, of course, the combining of an ATSC 3.0 digital television signal with that of an analog FM audio transmission.

The first station to try out the technology was Venture Technologies’ San Jose, Calif. Station, KBKF-LD, which began airing “second-gen” Franken signals last spring via an FCC Special Temporary Authority (STA) arrangement. 

This initial hybrid configuration was actually the creation of two RF technology companies, SYES (System Engineering Solutions) and Com-Tech. SYES’s vice president of sales for the Americas, Alessandro Annoni, provided a short history of the project.

“We worked together on this low VHF TV/FM combiner, beginning back in the late spring of 2020,” he said. “We designed a low-V transmitter working with a specific modulation/bandwidth and distortion, and a hybrid filter to avoid any type of interference or intermodulation. The amazing tech team of Venture Technologies, Daniel Bisset and Will Brownlie helped us to get this new system working in San Jose, back in February 2021.”

Jampro Antennas has also been working with LPTV Ch. 6 licensees to move to this new digital/analog broadcasting platform, with the company’s president, Alex Perchevitch, noting that while some amount of engineering effort was necessary to get the technology to the point where it could serve as a “proof of concept,” his company had earlier assisted analog Ch. 6 stations in delivering “standalone” FM radio services on 87.75 MHz.

“We were approached by a well-known consulting group on how to combine the FM audio with the Ch. 6 [video], and used modified diplexers similar to those we have produced since the 1960s for analog TV stations of various power levels,” he recalled.

Perchevitch said that his company’s recent grafting of 3.0 DTV with analog FM required the use of a modified Jampro VHF mask filter and some reworking the FM side of the operation to achieve a happy marriage. However, his company had a lot of experience working with installations involving the combining of multiple FM signals into a common antenna.

“This was not a new endeavor for us or one that required development of a new product group,” said Perchevitch. “We often supply FM combiners for frequency spacings as close as 400 kHz and this experience and product group provided the [expertise] and product to use for this hybrid TV/FM application.”

Even so, the initial assembly of a hybrid 3.0 DTV/analog FM Ch. 6 station did not exactly follow a “plug and play” script.

“We spent several months re-developing the filter technology to meet the requirements,” said Perchevitch. “Certainly, any time you are trying to combine frequencies which are so closely spaced and achieve high isolation with low insertion loss, it is a challenge.”

Franken FMs and ATSC 1.0?
In as much as the technology for combining closely spaced dissimilar RF signals has been available for some time now, one might naturally ask why such hybrid DTV/analog FM operations were not attempted by Ch. 6 licensees much sooner—perhaps coincident with the start of ATSC 1.0 broadcasting?

Actually, at least one full-power Ch. 6 station experimented with such a mixed transmission mode, but the results were less than satisfactory and the FCC refused to sanction it.

As explained by the Sinclair Broadcasting Group’s senior vice president of advanced technology, Mark Aitken, the reason for the failure of 1.0/FM pairing is simple. 

“ATSC 1.0 really precluded bifurcating spectrum occupancy,” he said. “As soon as you tried to shorten the bandwidth of the1.0 signal, you broke it; 3.0 is a different story.”

The Beginning of a Tsunami?
Could the apparent success of KBKF-LD and the other “second-gen” Frankens now on the air lead to the adoption of this hybrid mode of broadcasting by full power Ch. 6 operations? Perchevitch was asked if he saw any barriers that would preclude these Ch. 6 stations from airing dual-audience broadcasts.

“It’s certainly possible,” he responded. “And we believe it’s very possible that there will be more hybrid Ch.6 stations in the future.”

Perchevitch views this new breed of hybrid stations with optimism, as they squeeze additional utility of their 6-MHz chunks of spectrum, and added that he was not at all surprised at their rapid emergence.

“Lower power broadcasters and the consultants serving that industry have always been very creative in seeking ways to be competitive and generate revenue,” he said. “The use of CPOL (circular polarization) and EPOL (elliptical polarization) by LPTVs is a great example. Long before large numbers of full-power stations broadcast signals with EPOL or CPOL, LPTVs often were operating with elliptical or circular polarization. Franken FMs are all about addressing radios and the revenue from radio listeners, something [mainstream] TV to date has not been able to capitalize on.”

Bill Harland, vice president of marketing at Electronics Research, Inc. (ERI), was also not particularly surprised with the launching of what might be the vanguard of a common broadcasting practice.

“There are a number of Channel 6 LPTV stations in the U.S. that have been operating in major markets as FM stations for many years,” said Harland. “These are established facilities with significant listenership and the FCC rules do not specifically prohibit offering these ancillary services.”

On the other hand, Keith Pelletier, vice president and general manager of Dielectric, Dielectric, did express some surprise at the suddenness of the arrival of “second-gen” Frankens.

“It certainly caught me off guard,” he said, explaining that “the business model seems to be targeted for older vehicle receivers. In the future, as the older receivers get replaced it will be important to have a receiver that will go below 88 MHz, and not just vehicle receivers. Also, it will be an all-digital world at some point I would think, so analog services even in the FM world may go away.”

Nonetheless, Dielectric is ready to supply Ch. 6 TV stations with the technology needed to add analog FM if they desire to do so.

“Our sales team has been approached by multiple license holders,” said Pelletier. “We have manufactured two antennas to date and have discussed multiple more deployments that should happen in 2022."

He added that while the antenna portion of such a 3.0/FM installation wasn’t especially challenging, the combiner was a somewhat different story.

“In contrast to the antenna, the combiner needed more simulation work as well as development in the lab,” he continued. “This work was done using circuit simulation tools, HFSS (3D electromagnetic simulation software), and finally a prototype was manufactured to prove out the system.”

ERI’s Harland noted too that such combining of dissimilar signals was not especially challenging.

“ERI manufactures filters and diplexers that could be adapted for this application and we would design and manufacture the components required for a transmitter supplier to build systems for this application.”

At this point, the technology is in place, as are operators and their audiences, so it appears that only time will tell as to whether or not these Ch. 6 hybrid DTV/FM stations will proliferate, and whether the FCC will sanction their operations beyond STAs by moving the matter to the next rung and taking the necessary steps to codify their existence and operating practices.

WASHINGTON--The Federal Communications Commission today proposed rules to reimburse some low-power TV stations, TV translators and FM stations for costs resulting from the 2017 spectrum incentive auction, following up on a recent Congressional directive known as "The 2018 Reimbursement Expansion Act."

The act “expanded the list of eligible entities to include LPTV, TV translator and FM stations, provided additional funds to be used for this purpose, increased the funds available to reimburse full power and Class A stations and MVPDs and provided funds to be used for consumer education purposes,” the FCC said today. The statute also created a deadline of March 23, 2019, for the commission to adopt a Report and Order.

According to the NPRM (MB Docket No. 18-214; GN Docket No. 12-268), reimbursement will be available for LPTV stations and TV translators, “if (1) they filed an application during the commission’s Special Displacement Window and obtained a construction permit, and (2) were licensed and transmitting for at least nine of the 12 months prior to April 13, 2017.”

[Read: FCC Will Open April Window For Auction-Displaced LPTVs]

Additionally, the order says the Media Bureau should engage a third-party contractor to assist in the administration of the fund and also directs the bureau to determine cost eligibility and the reimbursement process. However, “the Media Bureau will consult with the Office of General Counsel and the Office of the Managing Director,” the order says.

The order also shares plans to use the $50 million provided by the REA for consumer education. According to the order, the commissioners “anticipate, among other initiatives, hosting a dedicated consumer service call center to provide consumers technical support and assistance on such matters as rescanning and other means to resolve potential reception issues. We also intend to perform targeted outreach to specific communities about rescanning, and we may use advertising spots to disseminate rescanning information. Consumer education funding could also be used in developing additional online resources...”

The NPRM also notes that the additional REA funds must be used no later than July 3, 2023.

FCC Chairman Ajit Pai said, “I’d like to thank Congress for passing legislation which provides additional reimbursement funds for full power and Class A stations, reimbursement funds for newly-eligible LPTV, TV translator, and FM stations, and funds for the commission to use for consumer education purposes.” Pai also thanked the commission staff who worked on the notice.

In his own statement, Commissioner Michael O’Rielly emphasized that he agrees with the reimbursement plans in general but thinks further input is needed before action. Specifically, he said, “While Congress carefully outlined how it intended FY18 monies to be spent, it provided less clarity for FY19. Should these funds be allocated similar to FY18 funds? Should television stations have priority? The answers to these questions will affect how interested parties are reimbursed for relocating during the repacking process...”

Additionally, O’Rielly questioned the validity of the “graduated reimbursement system” based on the idea that time equals money and asked for feedback and alternative proposed system(s) to allocate money.

O’Rielly also cautioned that the educational efforts should not duplicate “efforts undertaken by broadcasters or other stakeholders, or take on initiatives outside of [the commission’s] expertise, such as producing advertising spots.”

Finally, O’Rielly wrote, “I support edits in this item that will mitigate the use of delegated authority, as well as remove the tentative conclusion that third parties who made funding arrangements with LPTVs prior to the passage of REA are ineligible for funding.”

Commissioner Jessica Rosenworcel did not release a statement, but the Notice of Proposed Rulemaking and Order (FCC 18-113) indicated her approval and that of Commissioner Brendan Carr, whose statement was still pending as of writing.

[Read: FCC Allocates Additional $742 Million For Repack Expenses]

The NPRM “tentatively concludes that both full power FM stations and FM translators that were licensed and transmitting on April 13, 2017, using the facilities affected by a repacked television station, are eligible for reimbursement.” This includes “FM stations that incur costs to permanently relocate, temporarily or permanently modify their facilities, or purchase or modify auxiliary facilities to provide service during work on a repacked television station’s facilities.” Also, the NPRM recommends that the reimbursement process be “substantially similar to” that already used to reimburse full power and Class A licensees and MVPDs.

NAB Executive Vice President of Communications Dennis Wharton released a statement saying, “Earlier this year, Congress wisely authorized additional funding to ensure that tens of millions of Americans will not lose access to news, entertainment and lifeline information during the broadcast industry ‘spectrum repack.’ NAB is encouraged by the FCC proposal adopted today that closely mirrors the intent of Congress. NAB will be actively engaged during the rulemaking process to preserve live and local broadcasting on hometown radio and television stations, low power TV stations and TV translators."

For more information on the repack, visit TV Technology's repack silo.

RAYMOND, ME– Antenna and RF systems provider Dielectric has landed several key TV and FM radio deals in the Philippines in partnership with 90 Degrees North, Inc., a video and audio production, broadcast equipment supply and systems integration firm based in Manila.

90 Degrees North struck a partnership to sell and install Dielectric products last year to address a gradual DTV transition that is scheduled for completion in 2023, and a renewed investment in FM radio infrastructure by many broadcasters.

[Read: 2018 NAB Show: Dielectric Highlighting ATSC 3.0-Compatible Spectrum Repack Antennas]

Since striking the partnership, 90 Degrees North has landed several large RF contracts in the country. The most recent contracts include a Dielectric UT8D4-50 filter, Branch Combiner, Constant Impedance Filter (CIF) and Combiner, and transmission line deal with Broadcast Enterprises and Affiliated Media (BEAM), a subsidiary of the Globe Telecom conglomerate; and a turnkey FM radio deal with government broadcaster Philippine Broadcasting Service (PBS) covering antennas, filters and accessories.

The BEAM project will leverage Dielectric filters and combiners to simplify their DTV transition, allowing the customer to simultaneously broadcast analog and digital signals without requiring a complete tear down and rebuilding process along the way. 

WASHINGTON—From Radio World:“More PRSS stations may be affected by the FCC’s Broadcast Spectrum Auction than was originally reported” according to an updated report from the Corporation for Public Broadcasting,, the Public Radio Satellite System’sErich Shea writes.

The March 6 followup to “Potential Impacts To Public Radio Transmission Facilities From TV Band Repacking” says 191 CPB-eligible radio stations may be affected because these stations share transmission towers with one or more TV stations; and 53 of these stations share a tower with one or more TV stations currently operating on Channels 38-51, which will will either be repacked or go off the air.

Theoriginal reportpredicted 95 stations would be affected by the repack. The revised report lists all of the potentially affected radio stations.

Additionally, there are 304 CPB-eligible radio stations that are within 250 meters of one or more TV stations, which is double the number of stations identified in the February edition of the report. According to Shea, “these ‘near co-located’ stations may be affected by repacking to a lesser extent, but some may be required to eventually reduce their transmission power.”

The remainder of the report remains the same.