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9 posts

Wannabe Geek

Topic # 12767 4-Apr-2007 16:15
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Can someone shed some light?

I am running AsteriskNOW with a TDM400P 4 x FXO card. New - telepermitted etc etc.

everything works out-bound; great tone - all trunks etc.

When i call inbound - nothing but a dead line. Telecom have informed me that the PBX needs to issue a site-tone as the pilot wont ring with this configuration.

It is aparrenty a 4LC line 1 pilot 3 secondary trunks and two blocks of DDI's (passing 3 forward)

And ideas what i am doing wrong here?

Please help... if you can.

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2 posts

Wannabe Geek

Reply # 68802 29-Apr-2007 07:48
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I also have the same issue.  Does anyone know the steps to resolve this?

449 posts

Ultimate Geek
+1 received by user: 11

  Reply # 68810 29-Apr-2007 11:44
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Hi, if you have DDI you should be connected at the exchange on a 4LT card not a 4LC. are you set up to receive decadic (pulses) or DTMF tones? Can you get exchange dial tone going directly across the line? Cheers George


449 posts

Ultimate Geek
+1 received by user: 11

  Reply # 68811 29-Apr-2007 12:12
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hi, I am familiar with the exchange end but looking at the on line manual for your TDM400P card it looks like it is intended to only terminate POTS line service. There is no mention of DDI service on that card type at all. Geting nothing when you call suggests the exchange is set up for DDI but your end probably isn't. Check your card type. Hope this helps. cheers George

2 posts

Wannabe Geek

  Reply # 68812 29-Apr-2007 12:18
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I can get dial tone on the DDI lines and dial out etc. but all inbound calls receive a disconnect tone.  My assumption is that the TDM400P isn't generating the right tones back to the exchange.  I guess I may have the wrong card type if I want DDI support.  My other option is to get ISDN trunks.  Can't wait till I can trunk over our DDI blocks to SIP.


9 posts

Wannabe Geek

  Reply # 70794 15-May-2007 15:20
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ok. some progress; if not a very long process here.

After much no 8 wire has been applied to the setup i have a 99% solution with only one annoying issue.

6 lines

3 on a 4lt setup - standard hunt DDI Analogue two way lines
3 plain POTS lines (2 for fax internet / one for general use)

I have 2 Digium TDM 400p's
one with 3 x FXS and one with 3 x FXO

now; here is the trick;

The 4LT lines are expecting a line voltage from the PBX. aka. dial tone; by connecting and FXS port to this and changing the auto configured Zapdata configuration to from-zaptel instead of from internal for these lines they will recieve calls;

Telecom 'takes' the line off the hook and dials 3 digits; by setting up an inbound route for these three digits you can steer the call to an extenstion... aka DDI; but you loose the Caller ID.

I currently have the 3 FXO's connected to the other POTS lines for outbound, which is working great.

I am using fax passthrough to an ATA for the fax machines, works well.

no-one internationally seems to be using this setup.

It works; it's not an efficient use of lines, but it works...

Still a couple of bugs;

To do list ( read as please help!)

1. trying to initiate calls from the FXS (DDI 4LT lines). you can change the trunk grouping and get asterisk to pass the call down the FXS but it doesn't dial the tones until the line is lifted. Put another way; if you plug a two-wire handset into the FXS port it rings; then when the handset is lifted it dials the tones for the number you are wanting to call.

If it's possible to make the FXS take the line off hook and dial this will work... just don't know how.

2. Outbound works stellar; but on inbounds the call drops everytime when it reaches a 3minutes duration as seen in the FOP of trixbox...

This seems to be a known issue but i can't find anyone who knows the fix. help?

Hopefully this helps some of you other folks trying to re-engineer modern equipment to work with 1920's hangover PSTN lines...

If our local suppliers would stump up with reasonable priced ISDN for small business other than crummy 2 circuit BRA or $4000 install PRA with extorsionary monthly access all would be resolved.

449 posts

Ultimate Geek
+1 received by user: 11

  Reply # 70798 15-May-2007 16:18
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Hi, I have seen similar set ups suggested in forums at The downside though is you are paying for 6 trunks when only 3 bothway trunks are needed. Regarding your 3 minute disconection problem...I thing the exchange is waiting for an answer reversal....can you do this from the FXS cards? cheers George

9 posts

Wannabe Geek

  Reply # 70847 16-May-2007 09:33
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Not sure with the Answer Reversal from the FXS;

I definitely have clear forward and answer reversal on the lines; can i get this de-specified by TNZ?

I am running busy detect; so i should not have too many problems with disconnect supervision i guess.

Anyone know if you can do answer reversal on a digium FXS module?


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  Reply # 71270 19-May-2007 11:40
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What have you got for zapata.conf and zaptel.conf?

9 posts

Wannabe Geek

  Reply # 71852 23-May-2007 11:11
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; Zapata telephony interface
; Configuration file



rxwink=300  ; Atlas seems to use long (250ms) winks
; Whether or not to do distinctive ring detection on FXO lines



;Include genzaptelconf configs
#include zapata-auto.conf


;Include AMP configs

#include zapata_additional.conf


 Autogenerated by /usr/local/sbin/genzaptelconf -- do not hand edit
# Zaptel Configuration File
# This file is parsed by the Zaptel Configurator, ztcfg

# It must be in the module loading order

# Span 1: WCTDM/0 "Wildcard TDM400P REV I Board 1"
# channel 4, WCTDM, inactive.

# Span 2: WCTDM/1 "Wildcard TDM400P REV I Board 2"
# channel 5, WCTDM, inactive.

# Span 3: ZTDUMMY/1 "ZTDUMMY/1 1"

# Global data

loadzone = nz
defaultzone = nz

9 posts

Wannabe Geek

  Reply # 72460 28-May-2007 08:58
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I have had clear forward and answer reversal disabled on the lines and the 3 minute drop on inbound is still occurring.

Any more ideas?

449 posts

Ultimate Geek
+1 received by user: 11

  Reply # 72477 28-May-2007 10:03
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A feature of Telecoms NEAX switches is unanswered calls disconnect after 3 to 6 minutes.In your case the switch sends forward the digits, you supply the ringing tone, In a normal DDI PABX when the extension answers reversed line polarity is sent back to the NEAX . In the NEAX the call charging is set up and the disconnect  timer is stopped.In your case (no answer reversal  is sent to acknowledge) so in the NEAX the caller gets to call for free and is cut of after 3 to 6 minutes by the timer.
As to other solutions.....? Cheers George

9 posts

Wannabe Geek

  Reply # 72495 28-May-2007 11:22
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turn one corner find another brick wall...

Does anyone know of a voip card or gateway that supports DDI line types and asterisk?

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