NSW P25 GRN - Site Listing (current)

[DrClaw]

Thanks Mike for the info. Slowly getting back into scanning after a (too) long hiatus. Missed out on a lot.

Still rocking the 396XT and just bought a 536 for home.

Cheers!

[cartman]

On a general scan around noticed the following updates:

* Horsley Park (004-012 NAC 2D1) has changed control channel this week - now 419.025

* Mt Lambie (001-029) has changed Control Channel - now 420.3500 (unknown date)

* New Site online 001-032 on Control channel 419.1125 NAC 2D6 but not accepting radio affiliations yet.
Appearing as a peer on other sites: Roselands, Burwood Westfield, Revesby, Heathcote, Cabramatta
ACMA suggests Strathfield which originally was sighted as 001-089 a couple of years ago

* Mt Gibraltar has disappeared off the southern highland sites that i can monitor.
Update: Cell-on-wheels 004-116 is reported to be on location while site undergoes upgrade

* Berkeley Tops and Condell Park are currently offline with temporary cells-on-wheels in place
004-121 CC 423.7375 NAC 2D1 is covering Condell Park
Frequencies logged: 423.1125, 423.2375, 423.3625, 423.4875, 423.6125, CC 423.7375, 423.8625, SCC 423.9875, 424.2375, 424.3625, 424.4875, 424.6125 (all NSW wide frequencies)
005-123 CC 415.4125 appears to be covering Berkeley Tops

[DrClaw]

I was wondering what happened to Horsley.

Appreciate the updates!

[Mr Flibble]

Confirming Berkley Tops is still offline.

005-123 CC 415.4125 NAC 2DF temp cell appears to be covering Berkeley Tops as reported by Cartman
Frequencies logged: 412.4875, 413.4125, 414.6125, CC 415.4125, 415.4250, SCC 422.2375

[Mike Alpha]

* Horsley Park (004-012 NAC 2D1) has changed control channel this week - now 419.025

I've noticed with this change at Horsley Park, the active voice channels (according to Unitrunker) all show up on ACMA as having an azimuth of 270 Degrees. ACMA also shows the antennas used now are RFI directional offset dipole types.

So with the transmissions now favouring west, it explains why I can no longer receive Horsley Park at home on a portable.

Mike

[cartman]

In recent months I have been able to receive Bigola Plateau on 416.2625 Control channel and noticed on DSD that there is a new site active in the peer list that wasn't there earlier in the week.

Site 001-015 Killcare Control Channel 419.1000 (ACMA Site 35842).

(The old 001-015 Umina was renumbered 004-060 of course)

[Mike Alpha]

I was running Unitrunker on the new Strathfield site 001-032 (419.1125) with a discriminator signal from a 780xlt. The audio out of the 780xlt didnt sound the same as the usual P25 control channel sound, it was harsh and thrashy. I thought it might have been interference from an adjacent channel, but Unitriunker was decoding the site with 100% accuracy.

I checked the waveform on the UT scope and got the following

IMG_7122.jpg

CQPSK Modulation

(167.36 KiB) Not downloaded yet

A normal P25 waveform looks like this

IMG_7123.jpg

C4FM Modulation

(131.68 KiB) Not downloaded yet

After much Googling I found this new spiky waveform is showing a CQPSK modulation. The more sinusoidal looking waveform is C4FM modulation.

CQPSK modulation is used in LSM simulcast systems, so it looks like simulcast sites are coming. Many scanners have difficulty tracking simulcast systems.

This new Strathfield site is the only one I've found with the CQPSK modulation so far.

Mike

[Bigfella237]

G'day Mike, there are quite a few simulcast sites around and have been for many years, also referred to as "Hidden Host" sites here.

I have one end of a simulcast site near me (the Mt Budawang end of the Mt Cowangerong host site) and yes, I can confirm that it's CQPSK and my scanners don't like it (although all my scanners are dinosaurs now so I can't speak for the newer generation).

I can still decode the site but the signal seems to drop-out and come back, I made a YT video of this many years ago:

https://www.youtube.com/watch?v=-nybMCbqco0

[citabria]

G'day Mike, there are quite a few simulcast sites around and have been for many years, also referred to as "Hidden Host" sites here.

I have one end of a simulcast site near me (the Mt Budawang end of the Mt Cowangerong host site) and yes, I can confirm that it's CQPSK and my scanners don't like it (although all my scanners are dinosaurs now so I can't speak for the newer generation).

I can still decode the site but the signal seems to drop-out and come back, I made a YT video of this many years ago:

https://www.youtube.com/watch?v=-nybMCbqco0

None of those sites are simulcast. A hidden host site and LSM/CQPSK simulcast site are like chalk and cheese. Simulcast is when you have multiple transmitters at multiple sites, transmitting at the same time, on the *same* frequency, with the coverage of those transmitters overlapping.

I tried to view the YouTube video but got "Video unavailable - This video is private".

[Scotty]

None of those sites are simulcast. A hidden host site and LSM/CQPSK simulcast site are like chalk and cheese. Simulcast is when you have multiple transmitters at multiple sites, transmitting at the same time, on the *same* frequency, with the coverage of those transmitters overlapping.

My understanding is there are two types of simulcast - C4FM and LSM. The site Bigfella mentioned is one of the C4FM simulcast sites - a TX carried on one site will also be carried on the other site at the same time on the same frequency.

Until now there have been no live simulcast sites with overlapping coverage that would require LSM. This Strathfield site would be the first confirmed LSM site operational.