We would like to make changes to community radio broadcasting services in the Charleville, Augathella, Cunnamulla and Morven areas.
We want to vary the Charleville radio licence area plan (LAP). This will involve:
adding technical specifications for current transmissions of 4RR community broadcasting services at Augathella, Cunnamulla and Morven
extending the Charleville RA2 licence area to include the areas of Augathella, Cunnamulla and Morven
removing the technical specification planned for the now unused community broadcasting service in Cunnamulla RA1. This licence area will also be removed.
2MBS FM have been testing on & off at Artarmon for a week or 2, but as of today, I believe they are happy with everything & are now full time from Artarmon, albeit at around 1/3 of their normal full power.
Currently operating at lower than normal power on their smaller backup transmitter, while they move the rest of their PIE Racks & main transmitter from the CBD site to Artarmon over the next few weeks.
Earlier during my initial typing their was a high RDS BER during higher modulation levels, but that seams to have now disappeared.
RE RDS: Their āstandby transmitterā distinguishable with Group 0B data blocks instead of usual Group 0A. Also AF set with frequencies: 90.7 & 96.1MHz.
Since youāve noted that, Iāve started monitoring the signal here at work on our mod monitor, & am seeing some things, that Iāll have to let them know about. TXA have no control over whatās going into or the operation of their transmitter/s.
Do you have time to do some further monitoring & let me know what you find?
Iām seeing high RDS BER too at times, but Iām not surprised, their Stereo Pilot levels look to be quite high, Iām seeing up to 15kHz Pilot during loud periods & RDS levels up into 25-26kHz during the same, which I think is whatās causing the high RDS BER, the receivers are getting RDS overload because the RDS levels are too loud?
Iām also seeing the Group 0B data blocks, but Iām not seeing any Alternate frequencies?
Thereās no RT either, do they normally have that?
Thereās some loud music on now & the RDS is breaking up bad with high BER, stereo pilot levels up close to 20kHz & Iāve seen RDS levels hit 37kHz.
Date & time have just popped up on my mod monitor & they are out by a long way too but that could be due to the RDS errors? Do you see RDS time (CT) on 2MBS & is it correct?
I went digging in my archives & found a 2019 pic from SDR Console of 2MBS MPX & compared to current MPX. Also compared RDS level from our Australian RDS List.
Hereās what I note.
19kHz Stereo pilot level is the same as current -21dBFS normal.
RDS level was: -46dB FS now -40dB FS so RDS modulation level is higher.
Now comparing MPX shots I see a lot of power in the 19kHz harmonics on their standby TX. Big audio harmonics on 57, 76 & 95kHz.
Huge RDS harmonic on 76kHz.
I cannot measure modulation % indexes here or deviation, only MPX levels.
2MBS has never had RT (at least in recent years)
The AF frequencies are detected in RDS Spy with Method A.
The AF frequencies donāt show with SDR software program āSDR Consoleā.
2MBS does not have Date & Time (CT - Group 4A) & never has at least in recent years.
Iāve done another check & only Group 0B being transmitted.
RT uses Group 2A or 2B.
CT uses Group 4A (or 4b, never seen)
Hope that helps.
I wouldnāt worry about the AF frequencies, since itās only a standby TX & no other station using 2MBSās PI code of 2056.
Itās only the unfiltered 19/38kHz harmonics that is affecting the RDS. BW on medium modulation is very roughly around 280kHz.
Late Edit: 76kHz RDS harmonic is just -6dB below that of the 57kHz RDS subcarrier.
Yes noticing the lower signals in NW Sydney, quite weak in spots around Box Hill / Rouse Hill. The RDS is doing quite well hanging in except in the most weakest of spots.
Would the ERP be approximately 15-16KW in the 50KW zones?
89.9 Light FM will broadcast live from Melbourne Royal Show every day, from 12pm to 6pm AEST, according to the Show Guide inside Herald Sun today. The Royal Show runs from September 22 to October 2.
It was before my time there but apparently it wasnāt as good as Horsley Park. I think they were limited to using a vertical whip and the transmitter wasnāt well protected from the weather.
Thanks, good to know. I reckon Iād still get B-ROCK in Oatley as well, aiming west.
I have never heard 2NSB in Bungendore so thatās why I assumed vertical pol. B-ROCK is weak enough aiming towards Sydney (Mount Ovens is about 10 degrees north; Sydney is further round between 45-50 degrees NE).
