PSTN disconnect detection on Linksys 3102

[dsemkiw]

I am running 3cx version 8.0.10116.583 together with a coulpe of linksys 3102's and other bits & pieces. The 3102's are confirgured as gateways and ATA's and work almost perfectly.
I am having issues detecting PSTN disconnection. I am in Australia on the OPTUS network and can usually detect a CPC signal, however, this can take a relatively long time. I have been unsuccessfull in detecting a disconnect tone despite the various combinations I have tried after hours of painfull searching and testing.
Has anyone come across this issue?
Is there an authority that should supply the correct tone information or can someone suggest a tool or method that could be used to perform at test.
Could the gain, impedance or other PSTN settings be effecting the result?
Thanks in advance.

 

[leejor]

The most reliable method for detecting disconnect using the 3102 is the CPC (called part control) option, if your telephone company uses it. What happens is that when the far end hangs up first the line will go open for a very short duration. This will tell the equipment at your end that the called party has hung up or was otherwise disconnected. Many business systems make use of this to drop calls that are left on hold or in "limbo" (forgotten).

From what I've found, the disconnect tone used in Australia is: 425@-30,425@-30;1(.375/.375/1+2)

 

[ralexander]

Does anyone have a ideea what that would be for Romania?
I just searched the country code sets and it doesn't mention anything.Neither the World PSTN Tone Database.
I am curently using 480@-30,620@-30;4(.25/.25/1+2) .The only tone codes i found were this ones:

Romania
Busy tone - I (analogue) 450 0.15 on 0.18 off
Busy tone - II (digital) 450 0.17 on 0.17 off
Dial tone - 450 continuous
Number unobtainable tone - I 450 6x(0.11 on 0.092 off) 0.362 on 0.11 off
Number unobtainable tone - II (digital) 450 3x(0.092 on 0.11 off) 0.362 on 0.11 off
Ringing tone - I 450x25 1.85 on 4.15 off
Ringing tone - II 450 1.5 on 4.5 off

 

[leejor]

You should have really started your own thread.

Since most, if not all of the tones used in Romania seem to be made up of a single tone ,450 Hz, then I'm going to go out on a limb and guess that a disconnect tone would be the same frequency. It is just a matter of the cadence and level. Since, I assume you live there, you could compare it with a busy tone or fast busy and see how close it is to those. It may not have to be "right on" to work for you.

If you find a country close to Romania, that uses most of the same tones in dialtone and busy, then the disconnect tone may also be the same. If they are using recent (last 20 years) telephone equipment, then they may have acquired it from the same supplier and therefore may well use the same tone schemes.

 

[dsemkiw]

Thank you for your reply.
Disconnecting using CPC is successfull, however, it takes 10 seconds for the disconnect tone to start which then continues for 35 seconds before the CPC signal is recieved.
The result is often 10 seconds of silence followed by 35 seconds of disconnect tone recorded at the end of voice mail messages if the caller simply hangs up.
I have tried 425@-30,425@-30;1(.375/.375/1+2) together with a number of variations.
I suspect that the PSTN to SPA gain settings may be incorrect as, even though most sources confirm the values, the call volume appears lower than that on calls using a voip provider. I assume that this gain will inturn affect level and recognition of tones.
Are there any tests that can be performed in relation to levels & tones?

 

[leejor]

Disconnecting using CPC is successfull, however, it takes 10 seconds for the disconnect tone to start which then continues for 35 seconds before the CPC signal is recieved.

That's odd, usually the CPC (momentary loss of battery) is sent immediately after the CO switch detects a disconnect from the far end and is sent long before the disconnect tone. I guess it depends on the manufacturer of the CO equipment. The CPC is only used if you don't hang up but the PSTN end does. When you hang up from the VoIP (3CX) side , the 3102 should drop the call almost immediately, if it's not then you need to investigate why not.

Are there any tests that can be performed in relation to levels & tones?

I suppose, if you had some semi professional test equipment but you are probably going to have to go with the "trial and error" method. Every phone system is different so there is no one solution.

 

[dsemkiw]

Thank you for your reply. Yes, a hang up from the 3CX side works fine.
The main issue is for incomming PSTN callers who leave voicemail messages.
I will keep trying to disconnect using the disconnect tone and will post the result if successfull.
In the meantime ... if anyone else has had success here ... I would be happy to hear from you.

 

[Elis]

I have a problem with call transfer, I can not transfer calls from analog phone that is connected to SPA-3102
when I press the button "hook" the signal doesn't change.I.m still online with the person to whom I was talking before
What problem do you think can be :idea:
regards

 

[dsemkiw]

I had the same issue some time ago.
Try adjusting the Hook Flash Timer Min & Max values in the regional tab under Control Timer Values (sec).

 

[Elis]

Thank you for your answer, but is the same situation, again not funksion ???

 

[leejor]

Try adjusting the Hook Flash Timer Min & Max values in the regional tab under Control Timer Values (sec).

That won't have anything to do with disconnect, that is to adjust the time so that the 3102 will recognize an actual hook flash from a set on the FXS port.

 

[dsemkiw]

Yes, I was referring to recognising a hook flash. Not really relevant to this post though...