That RDS issue I’ve had (mentioned last couple of weeks here), with trying to tune Hit Newcastle & getting Nova Sydney works in reverse too.
At home today, I tried tuning Nova & Hit Newcastle came on, I also tried to tune 2DAY FM & Todays Country 94.1 came on, it’s obviously something to do with the frequencies & probably PI code’s being similar, (having the same figures contained in them), & the receiver tuning in the strongest signal as long as it’s “close enough”.
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Yup. No surprises there given your previously mentioned fault details.
Yes similar frequency pattern like before, but also similar PI codes in terms of binary bits.
Lets look at the PI code of 2DAY FM & Today’s Country.
2DAY (104.1) has a Hex PI code of: 2041 = 0010 0000 0100 0001
Todays Country (94.1) has a Hex PI code of: 2941 = 0010 1001 0100 0001
Again there’s only a two binary bit difference in the PI code, re 2nd digit 0 vs 9, else the PI code is the same. This is basically the identical issue you and @Radiohead experienced with NOVA & Newcastle’s Hit.
The RDS frequency switching decision making process is always done by the radio tuner (firmware/software) & I suspect in the tuners concerned that they allow for a one to two bit error without error correction when making a decision. You would think the tuner would also look for a AF frequency in group 0 block before making a switching decision. I know there is error checksums in the RDS group blocks. I’d have to go & consult with docs again to determine if there’s also error checksum for the PI code.
What I can’t figure is that there is only a one binary bit difference between 2DAY’s & Triple M (Sydney’s) PI codes.
2041 (2DAY) 0001 (4th digit) 104.1
2049 (Triple M) 1001 (4th digit) 104.9
So why aren’t people having RDS switching errors?
Is it something to do with the frequency number or the RDS AF filler?
I initially wrote another 8 paragraphs after this, but decided to leave the comments to later if required. That said, to be super brief; I feel ACMA needs to be involved or be the regulator in PI allocations. I also think that perhaps an app needs to developed to generate a PI code that isn’t going to create problems that many listeners & radio stations have experienced.
Can I ask you @RFBurns did you make any official representation to Nova & SCA or SCA & Today’s Country?
I am aware that both Today’s Country & Pulse 94.1 (which share the same PI code) & both stations border the Sydney LAP, were requested to change their identical 2941 PI code, neither station bothered to act.
Here’s another case for a regulator to assume the role of RDS PI code issuing & where that regulator is aware of the various technical issues surrounding poor PI code choice, eg 0000, any code beginning with 0 or FFFF etc.
BAI, the ABC/SBS, CRA, CBAA & the large commercial broadcasters etc ARN, SCA etc should get together with ACMA to discuss the issue.
I’m still building on my knowledge of RDS.
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I haven’t, I can probably see what Today’s Country can do, I think I know the tech they’re using (contracted-in tech when needed).
Nova I doubt will be interested in doing anything, as it’s kinda benefiting them & is out of their licence area when the issue arises?
SCA you’ve got to be kidding, they will have no interest, something else to throw in the mix that could have something to do with it, or any other issues with SCA RDS & reason behind what I’ve just said.
The RDS sub-carriers must be within +/-10 degrees from the stereo pilot phase or in quadrature & within +/- 10 degrees of 90 degrees from the stereo pilot phase, the SCA RDS carriers are outside this & makes the transmitters fail the yearly Proof Of Performance tests we carry out at TXA, TXA have been chasing SCA to fix this for a number of years now, with no luck, SCA RDS is managed in-house, TXA can’t do anything with their RDS, I believe Sydney isn’t the only place that suffers this RDS issue with SCA.
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That’s cause most of there good techs got the arse, some of the techs that are left likely don’t even know how to fix the issues sadly
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Also experiencing similar with Nova Bris and ZZZ Lismore in low signal areas.
Have done so since RDS switch on by ZZZ Lismore
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The PI itself doesn’t have a checksum, but the intention is that the second digit was intended as a “coverage area” indicator (after the first hex being a country code - less important here when nowhere near FM distance of most other countries). It sounds like part of the idea was that in some places, relevant administrators would reserve a group of PIs differing only in the second “coverage area” hex, as an added hint to switching between different stations of a regional/national network.
For instance, in the North American version of RDS (https://web.archive.org/web/20161020015638/http://www.nrscstandards.org/SG/nrsc-4-B.pdf), there were some reserved PIs for national networks that differ regionally - which over there is really limited to the CBC/Radio-Canada national networks plus some reserved for NPR - which would only differ by the second hex digit. It’s possible that this happens more generically on some receivers… I would have thought that it would have required AF to be advertised too, but I thought AF was meant for alternative uses for the same station like infill transmitters. 
I don’t know whether the same issue would happen over there with commercial stations not using the reserved “national” PIs, but given they use a formula to create PIs based on their callsigns [in the US at least, it has nothing about how, say, Canadian and possibly Mexican authorities deal with it], the likelihood of a clash like this is a bit less likely. Of course it sounds a lot more lax in Australia; in Europe I imagine they’d assign PIs more thoughtfully.
I hadn’t seen much of that being used properly in Australia but Radio NZ across the ditch made a big song and dance about their RNZ National stations being linked this way fairly early on, and I suspect that’s how they would have had to do it.
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And I kinda noticed as to how those two examples you gave were given PIs based on frequency (2941 for 94.1, eg.), or so it seems… that’d also explain why Hit Newy (106.9) and Nova 96.9 might’ve had the same problem, as if it follows the same format it’d differ in the same hex. Nova Bris (106.9) vs 2ZZZ (100.9) may well be an error correction thing but I guess it depends on what ZZZ uses (as I’m under the presumption that regional stations may have a different assignment format than metro stations).
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I totally forgot about that PI code’s meaning something with the first 2 digits & Australia not using them as the RDS standard expects.
Therefore the receiver is looking at the last 2 digits & they are in many cases the same, so it’ll tune the strongest signal as it’s expected to do under the RDS standards.
This is taken from the Pira RDS web site:
PI - Program identification
This information consists of a code enabling the receiver to distinguish between countries, areas in which the same program is transmitted, and the identification of the program itself. The code is not intended for direct display and is assigned to each individual radio program, to enable it to be distinguished from all other programs. One important application of this information would be to enable the receiver to search automatically for an alternative frequency in case of bad reception of the program to which the receiver is tuned; the criteria for the change-over to the new frequency would be the presence of a better signal having the same PI code.
The PI code consists of four characters. The first two characters have special meaning, second two are used to clearly identify different stations.
The first character identifies country. The second character identifies program type in terms of area coverage:
0 - Local (Local program transmitted via a single transmitter only during the whole transmitting time.)
1 - International (The same program is also transmitted in other countries.)
2 - National (The same program is transmitted throughout the country.)
3 - Supra-regional (The same program is transmitted throughout a large part of the country.)
4 to F - Regional (The program is available only in one location or region over one or more frequencies, and there exists no definition of its frontiers.)
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That’s an unusual one.
Nova on 106.9 with PI of F106
ZZZ on 100.9 with last reported PI of 2009
Binary code of 4th digit is 0110 & 1001 respectively, all 4 bits are different.
The closest similarity is with the frequency.
Can anyone confirm PI’s of both stations?
Have you tried a software reset or firmware update of your car tuner?
I really do wonder about the firmware of a tuner that would cause a automatic frequency switch in that case. I’m bewildered.
I also ponder if the basic RDS PI standard model that the RDS authorities created was thought through sufficiently all those years ago? Perhaps PI code should have been a 20 bit binary or 5 digit hex code.
Using only 3rd & 4th number to define a unique station PI code; 16^2 only provides for 256 local station combos for each state. PI code allocations using the RDS authority standards model would require careful coordination by a national body or group.
The potential for switching problems does depend on the decision making process of the tuner’s firmware programming with PI codes, ie only looking at last 2 characters of PI code or all 4.
Is it possible & I only timidly suggest this, but if a station that is experiencing listeners having their tuners incorrectly switch, that possibly adding Group Code 1A or 1B, which contains the ECC (Extended Country Code), ‘might’ help reduce or eliminate incorrect switching if that other involved station (switched to in error) doesn’t have a ECC & they don’t wish to change their PI code. Australia’s ECC is F0.
Out of interest there’s only 3 stations in Sydney that’s using Group Code 1A.
- 99.3 Northside Radio (Chatswood) ECC F0 (Australia), but they have a PI code of 1993, which incorrectly indicates that the station is in the ACT with ‘SDR Console’ software, due to their selection of digit 1 as their 1st digit of their PI code.
- 104.1 2DAY FM with ECC of F0 (Australia), PI 2041 (2=Area of NSW), 0 = local transmitter, 41 = Station ID
- 105.7 Triple J (Syd) with incorrect ECC of 00, PI is 2D5F
I was having a look at NZ’s RDS station list on our Google Sheet & NZ has programmed their RDS PI allocations very well according to the standard with the odd small station exception. RNZ National has done what appears to be perfect job.
RNZ National & RNZ Concert also appear to using an ECC with group 1B, which contains a repeat PI code, combined with their multiple AF’s across all of their RDS transmitters I suspect their RDS TX switching would work well.
It seems obvious reading everyone’s recent comments of the problems experienced, that the CRA should scrap its unique RDS PI code model.
That would be a great start re conflicts with 2DAY & Pulse 94.1 Illawara’s PI & swiching errors.
Pity about that, but given what we see with 2DAY’s PI code & ECC - it all looks good.
As SCA use TMC with SUNA & HERE throughout cities & some larger regional centres, this might complicate some resolutions along with other reasons provided by McPaton in past.
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Not good.
BTW when I look at the FM MPX spectrum of CADA 96.1 there’s very nice filtering & protection of their stereo pilot carrier & RDS carrier from the program signal, so much better than the majority of other FM broadcasters.
Is their something unique about CADA’s 96.1 transmitter or encoders or other such tech equipment?
BTW @RFBurns I note that Group 4A Clock Time (CT) has been added (recently?) to CADA 96.1’s RDS but the UTC offset for CT appears to be incorrect. Do you have any contacts at ARN to investigate this?
I also note they have added TP flag.
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Standard filtering on the Omnia 9 processor they use for MPX on 96.1 (in comparison to the Orban on 101.7 & 106.5).
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Thats been incorrect for a while even during The Edge days, it always messes with my clock radio (as it takes the time from the radio RDS)
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TXA have nothing to do with the CADA 96.1 transmissions, I’m not sure how much ARN have with it, (other than own the site & supply the programming), that transmitter & associated is looked after by the same contract tech who looks after 2LT/MooveFM, ARN probably control the RDS, I can ask the techs tomorrow if I think of it, at our Christmas get together.
I’m only guessing CADA is done the same way as WSFM & KIIS, in that case the RDS is injected post processing, so the Omnia processor filtering will have no affect on that.
It’ll also depend on what input to the transmitter exciter they are using as to where the stereo pilot is generated, MPX or AES?
WSFM & KIIS have 2 processors, an Optimod which feeds MPX & a Wheatstone FM55 which feeds AES, they’re currently using the Optimod’s, so they will be generating the stereo pilot, if they switch to the Wheatstone’s, the Nautel transmitters will be generating the stereo pilot.
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Damn how does one get invited to that 
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Have to be an employee, client or shareholder of TXA.
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Odd thing was when I last updated CADA’s RDS on our Google Sheets spreadsheet recently there was no CT & the station didn’t have TP & used the following RT messages:
CADA - Never Miss A Beat
Now: [Title] - [Artist]
Just Played: [Title] - [Artist]
Now: TP flag & only the following RT message:
Australia’s home of Hip Hop and R&B
Currently with their CT the CADA tech has set the local time under the UTC time field in software.
At 1247 actual local time: RDS setting has UTC showing as 1247 & our local time therefore incorrectly showing as: 2347
That would be great @RFBurns Have a great x-mas party.
@TheChase I have in the past contacted the receptionist at ARN re a clock set issue.
I can’t recall which of their 3 greater Sydney stations it was now.
I think the problem was resolved fairly quickly.
Listeners should be reporting these issues.
@gordo92 Some of the things I’m seeing with BAI’s management of RDS of ABC in Sydney & Brisbane doesn’t instil me with much confidence of their technical prowess or understanding of RDS either.
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Seems sadly most of the good engineers have been Burnt and left the industry
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2GF now has RDS operational on 89.5
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That’s good news!
How is it being displayed eg. 2GF 89.5.
89.5 and 90.7 are the only two frequencies I’ve never seen RDS on…
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