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any brief old recordings of old 6ds network? selcall sound

Posted: Tue Aug 23, 2011 11:09 pm
by slipknot
Hi all.
I know its against the "Responsible scanner users" rule of the forum , but I was wondering if anyone had a breif recording of the old 6DS network in action.

The main idea is that im trying to find out the format and number length of 6DS`s old Selcall system. If any one had a short brief recording of the old system in action with a selcall burst, I could use a program called Wintone to decode it.

Thanks.

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 2:59 pm
by vk6hgr
Best I have is from Railways

http://vk6hgr.echidna.id.au/sound/selcall.wav

If I remember right it was 60ms CCIR in two groups - a 5 digit selcall immediately followed by the mobile responding with it's own selcall number. (a typical Philips setup)

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:06 pm
by slipknot
Thanks Gav, silly me, I forgot to mention that I was referring to the selcall that the ambulance sends out everytime an ambulance driver contacts 6ds, although That selcall tone was rather long, and sounded like it was about 10 digits in length?

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:08 pm
by slipknot
Just had a listen then, is that the railway or ambulance? sounds just like it to, even has the number sequence and then with the misterious pause followed by a final digit, (thats another thing I cant figute out). :?

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:10 pm
by Infernal
I dont recall ever hearing a SELCAL when we contacted 6DS, only a Rodger tone

They only SELCAL was the DEPOT Call and the Priority one Tone

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:16 pm
by vk6hgr
slipknot wrote:Just had a listen then, is that the railway or ambulance? sounds just like it to, even has the number sequence and then with the misterious pause followed by a final digit, (thats another thing I cant figute out). :?
The recording is definitely Westrail. I have a bunch of Philips gear and I programmed them up to try and figure out how they did that gap is but I never did get it out either. I think it's a Motorolaism as Philips gear can't put a blank space in a selcall sequence. I don't think the radios on the 6DS network did it.

6DS used selcall and ANI. The sequence went something like this:

6DS: "6DS to Warwick. Priority 1 pending" - sends 5 digit selcall number
mobile: - same 5 digit selcall acknowledging
(long tone)

mobile: "6DS, Warwick" - 5 digit ANI

(etc)

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:28 pm
by Infernal
Sorry Gavin, i don't think that's how it went

for P1 there was a tone

TONE : Priority one pending in Warwick

6DS looks for the closest mobile ambulance not already assigned to a P1, the following call would be KINGSLEY 21 they would respond and then be assigned the job

If Kingsley Depot was the closest, a SELCAL would be sent

The radios in the DEPOT auto mute, when they receive the SELCAL they un mute, and 6DS sends the message, then the radio would mute, the officer would pick up the handset and cycle it once to acknowledge the call, unless it was the first call for the day, the crew would respond with their crew number and vehicle number.

Example of P1 Depot call

TONE : Priority one pending in WARICK

SELCAL (depon radio un mutes) KINGSLEY DEPOT good morning P1 in WARWICK, what crew and Van
Officer : KINGSLEY 21 in van 43
Depot radio goes back to mute.

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:33 pm
by vk6hgr
It's been a while, so the memory is obviously a bit fuzzy :)

On the radio side of things, there was definitely a 10 digit selcall sequence there though that was clearly automatic - 6DS sends the selcall page and the mobile responds straight away with its own number, which ended up sounding like a long 10 digit selcall (which is what Philips gear does by default)

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:36 pm
by vk6hgr
On a related topic, why does Transperth train security use selcall ANI? They don't seem to actually use it for anything.

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:38 pm
by Infernal
Im confused, are we asking about a

SELCAL
used to alert some one that a call is coming through

or a Rodger tone
Used at the end of the call to denote the end of the transmission

The tone played before AFAIK was called a Rodger tone

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:43 pm
by vk6hgr
AO11912 wrote:Im confused, are we asking about a

SELCAL
used to alert some one that a call is coming through

or a Rodger tone
Used at the end of the call to denote the end of the transmission

The tone played before AFAIK was called a Rodger tone
Good point.

Radio-wise they're the same thing. The radio has it's own 5 digit code and is programmed to accept selcall pages and/or insert its number after the push-to-talk switch is pressed. 6DS analogue happened to do both. Transperth security seems to only do the latter. They're still the same tones, though, just different uses.

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 9:47 pm
by Infernal
yes 6DS had both

But only the Depot radios had a SELCAL

The radios in the vans were live so to speak....

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 10:10 pm
by slipknot
I was referring to the roger beep, which happened to be a selcall sequence that the radios would emmit, I tried with some icom gear aswell and cant put the spacer before the last digit.

Re: any brief old recordings of old 6ds network? selcall sou

Posted: Wed Aug 24, 2011 10:41 pm
by slipknot
Also from memory when I was in Margaret River Ambulance, in 2007, two of our vehicles had simoco radio, which ddnt emit selcall, but our main ambulance did hae selcall roger but was an old looking radio, cant remember what type, the strange thing about that was that from what i could see, there was a huge massive VHF country network set up down there but A, not all sub centers knew it was possible to contact 6DS from the country or how to use it, and there must have been a broken link berween busselton and margaret river, isolating everyone else below the cut off line, A VHF frequency based on a repeater in yellingup enabled me to hear activoty, but i only ever heard waroona, harvey and on one occasion, lancelin??? Even asked the sub center manager about the network, and all his response was something like , "well no ones told ne about it?". you head up to busselton and there appears to be a second country network setup up there,