RDS Question

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Larry Milliken
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RDS Question

Post by Larry Milliken » Sat Aug 03, 2019 11:40 am

If a station is running RDS and has translators fed off air via a composite signal, is it legal to filter out the RDS on the translators so each one may transmit its own RDS data?

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Deep Thought
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Re: RDS Question

Post by Deep Thought » Sat Aug 03, 2019 11:54 am

There is no provision in Part 74 for "originating" RDS at the translator in that manner, so no.
§74.1231 Purpose and permissible service.

(b) An FM translator may be used for the purpose of retransmitting the signals of a primary AM or FM radio broadcast station or another translator station the signal of which is received directly through space, converted, and suitably amplified, and originating programming to the extent authorized in paragraphs (f), (g), and (h) of this section.
Paragraphs (f) (g) and (h) do not mention RDS insertion different from that of the primary signal.
Mark Mueller • Mueller Broadcast Design • La Grange, IL • http://www.muellerbroadcastdesign.com

Larry Milliken
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Re: RDS Question

Post by Larry Milliken » Sat Aug 03, 2019 7:40 pm

Thank you, Mark. I thought as much but wanted verification from someone more astute. Now, I have an answer for the manager if and when it come up.

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Re: RDS Question

Post by TPT » Sun Aug 04, 2019 6:30 am

I would disagree. Look at 47 CFR Section 73.293, 73.295 and 73.319. While there are technical standards for "subsidiary communication services" there are very few restrictions as to what is transmitted, including data signals for various purposes. RDS would fall under these sections.

Then looking at Section 74.1231, the focus is on programming. Now, one caveat, would be where the translator is owned by a third party. Since the licensee is still responsible for the material carried on a subcarrier , 73.295 (e), I don't think you could have an independent transmission on a translator's RDS.

However, I see nothing that would prohibit a co-owned translator from running any kind of legal material on either an SCA or RDS subcarrier. Particularly information on the RDS subcarrier of a translator relaying the programming of an AM station. One example of this would be the translator's call sign, in lieu of either voiced announcements on the main carrier, or Morse injections into the translator carrier.

A related example of this that was popular back in the 70's and 80's was the carrying of commercial (e.g.: paid) background music services on the SCA's of non-commercial stations. True, SCA was considered a "subscription" service at the time, but SCA receivers were widely avaialble

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Re: RDS Question

Post by Deep Thought » Sun Aug 04, 2019 3:04 pm

Larry said this was OTA pickup, which almost certainly means it isn't a "fill-in", and even if it was there is no provision for stripping RDS off the received signal and substituting some other RDS data in its place.

This is a translator, not a Part 73 station, and the rule says "originating programming to the extent authorized in paragraphs (f), (g), and (h) of this section" which means only those items listed are authorized. Those sections read:
(f) A locally generated radio frequency signal similar to that of an FM broadcast station and modulated with aural information may be connected to the input terminals of an FM translator for the purpose of transmitting voice announcements. The radio frequency signals shall be on the same channel as the normally used off-the-air signal being rebroadcast. Connection of the locally generated signals shall be made by any automatic means when transmitting originations concerning financial support. The connections for emergency transmissions may be made manually. The apparatus used to generate the local signal that is used to modulate the FM translator must be capable of producing an aural signal which will provide acceptable reception on FM receivers designed for the transmission standards employed by FM broadcast stations.

(g) The aural material transmitted as permitted in paragraph (f) of this section shall be limited to emergency warnings of imminent danger and to seeking or acknowledging financial support deemed necessary to the continued operation of the translator. Originations concerning financial support are limited to a total of 30 seconds an hour. Within this limitation the length of any particular announcement will be left to the discretion of the translator station licensee. Solicitations of contributions shall be limited to the defrayal of the costs of installation, operation and maintenance of the translator or acknowledgements of financial support for those purposes. Such acknowledgements may include identification of the contributors, the size or nature of the contributions and advertising messages of contributors. Emergency transmissions shall be no longer or more frequent than necessary to protect life and property.

(h) An FM translator station that rebroadcasts a Class D AM radio broadcast station as its primary station may originate programming during the hours the primary station is not operating, subject to the provisions of §74.1263(b) of this part.
Where do you see permission to do that?
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Re: RDS Question

Post by TPT » Sun Aug 04, 2019 5:08 pm

What is "programming?" And what is data?

The key here is who owns the translator? Off-air is still commonly used by co-owned translators.

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Re: RDS Question

Post by radio_guru » Sun Aug 04, 2019 7:49 pm

Deep Thought is right. Except for the FSK legal ID, all items carried on the co-owned main emission must also appear unaltered on the translated signal of a co-owned translator. The only exception is a commercial translator not affiliated with the main station licensee where the translator owner may run one commercial an hour. This is specifically allowed in the rules.

Otherwise, it must replicate 100% the entire base band.

MM

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Re: RDS Question

Post by kcbooboo » Mon Aug 05, 2019 4:03 am

So what does that mean for a translator that's picking up the primary station's HD2 signal OTA with an HD receiver and retransmitting that as a low-power analog stereo FM signal on another frequency? Where does the RDS data come from? Or isn't this a true translator in the sense that the baseband signal is not being sent out elsewhere?

Bob M.

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Re: RDS Question

Post by kkiddkkidd » Mon Aug 05, 2019 5:51 am

kcbooboo wrote:
Mon Aug 05, 2019 4:03 am
So what does that mean for a translator that's picking up the primary station's HD2 signal OTA with an HD receiver and retransmitting that as a low-power analog stereo FM signal on another frequency? Where does the RDS data come from? Or isn't this a true translator in the sense that the baseband signal is not being sent out elsewhere?

Bob M.
I don't have anyone using this "style" of translator yet but in my opinion, the precedent set when the FCC allowed HDx streams to be retransmitted on analog translators, pretty well negated all of the exact content rules that Mike mentions.

I do work for a small group that has been approached about allowing a 3rd party to install HD equipment at one of their FM's in a top 100 market for the sole purpose of feeding xlators. They are checking out the logistics and legalities of the offer right now.
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Re: RDS Question

Post by TPT » Mon Aug 05, 2019 6:33 am

There are many instances of HD subsidiary signals being relayed by a translator. Some of these HD signals are leased to be relayed by a third-party owned translator.

The only problem with allowing a third party to lease an HD stream to be broadcast (and I use the word for a reason) on a translator--is that the licensee of the main station (the one with the HD being relayed) would still be responsible for the content of the HD subsidiary signal being broadcast on that translator.

Case in point showing the risks of this legal entanglement is that of the AM station in the DC area carrying RT radio, which was also relayed on a third party owned translator. RT radio is a propaganda feed of the Russian government, the station was required to register as a foreign agent (which I suspect would eventually fall to first amendment concerns, but no matter, the point is legal harassment which is an advanced art in DC).

Anyway--that the FCC allows translators to relay HD subsidiary signals (e.g. HD-2 with separate programming) would also, by implication, answer the question about a separate RDS data feed on those translators. Both signals are "separate" or "supplemental" signals to the signal on the main carrier.
From a "theory" point of view---what if the HD-2 signal carried title and artist of the music programming on the HD-2 signal? To duplicate the characteristics of that HD2 signal, would not it make sense to use RDS to provide the same title and artist information on the analog signal of the FM translator?

Of course, given that the Commission has a hard time getting daytimers to power down to flea power at night (listen to the AM band some night)--or even enforcing part 15 regulations to quiet the noise that is killing these same AM stations--I would not worry about running a separate RDS feed on a co-owned translator.

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Re: RDS Question

Post by radio_guru » Mon Aug 05, 2019 8:50 am

Relaying the HD subchannel as an analog emission on a translator is permitted and it may originate RDS in that regards. But the content must also be present on the host/parent station. This is the rare instance other than the permitted one sponsorship per hour which the translator can "originate" content. Otherwise, it's a total baseband pass through for a conventional translator.

RG

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Re: RDS Question

Post by Deep Thought » Mon Aug 05, 2019 8:58 am

kcbooboo wrote:
Mon Aug 05, 2019 4:03 am
So what does that mean for a translator that's picking up the primary station's HD2 signal OTA with an HD receiver and retransmitting that as a low-power analog stereo FM signal on another frequency? Where does the RDS data come from? Or isn't this a true translator in the sense that the baseband signal is not being sent out elsewhere?

Bob M.
Those are fill-in and are a special case the FCC created via policy. There is no rule covering it, but even those can't put RDS data independent of the programming they carry.
Mark Mueller • Mueller Broadcast Design • La Grange, IL • http://www.muellerbroadcastdesign.com

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Re: RDS Question

Post by Deep Thought » Mon Aug 05, 2019 9:01 am

kkiddkkidd wrote:
Mon Aug 05, 2019 5:51 am
I do work for a small group that has been approached about allowing a 3rd party to install HD equipment at one of their FM's in a top 100 market for the sole purpose of feeding xlators. They are checking out the logistics and legalities of the offer right now.
Those will still be considered fill-in, and even if the HD2/3/x are leased the programming is still the responsibility of the originating station.
Mark Mueller • Mueller Broadcast Design • La Grange, IL • http://www.muellerbroadcastdesign.com

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