Availability of NV Fax Detect in latest FreePBX Distro

Hi everyone. This is my first post in this forum and I am a beginner with FreePBX and in general with the asterisk.
However this is the question:
the “NV Fax Detect” method to detect incoming fax calls does not seem to be available in the latest Freepbx distribution. Is there a means to install it, even from the source?

I can provide more information on the setup of my configuration, but essentially I would like to route incoming faxes to FreePBX (VM on esxi host) to another machine running Debian (another VM on the same esxi host) with IAXModem and Hylafax server installed.

I’ve only a number from my VOIP provider ad i’m finding a method to distinguish fax from voice calls.

Using the same number for voice and fax has various issues and is generally not recommended. In most developed countries, numbers cost next to nothing and you should just get a separate number for fax.

If you have a good reason to share a number (you have printed brochures or business cards with the same number for voice and fax, or you are in a place where numbers are expensive), the fax detection built into FreePBX will do as well as NVFaxDetect. They both work fine, but waste four seconds of the caller’s time (and trunk time) on every voice call.

If your voice calls are always answered by an IVR, what might work better is

which could listen for CNG tone and DTMF during the initial announcement. Be prepared to write a fair amount of custom dial plan to make it work well.

However, if you plan to send voice calls to an extension, ring group, etc., then you are stuck, even in theory. You either waste the caller’s time while you decide he’s not a fax, or you needlessly disturb the human agents by ringing their phones on every fax call (and if they answer too quickly the fax will fail).

Thanks Stewart for your kindly and useful response!

I know, but mine is a home setup of FreePBX and I would like to avoid registering with another VOIP provider just to get a dedicated fax number, also assuming that I may only receive faxes occasionally. The fax server, for inbound faxes, is only an additional service seldom used.

I would like to detect incoming faxes and route them to the appropriate extension (like I said a hylafax server with IAXmodem on another VM machine). For this I would like to avoid setting up an IVR just for home calls. From the Freepbx wiki (as as new user I cannot paste the corresponding link) I assume the best solution to my situation is the use of the NV Fax Detect application only that, as stated in the wiki, this “Requires NV Fax Detect to be installed and recognized by an asterisk”, which it is not.

Thing that I would like avoid (see my previous response)

I plan to to send voice calls to ring groups and extensions (see also my previous responses).
I add that, apart from the seemingly unavoidable need to compile the missing modules from the source, I would like to configure the PBX from the FreePBX Web Intrface and not write custom configurations from the command line in order to keep the configuration clean and update-proof in the future.

Why is the built-in fax detection (Inbound Routes -> Fax tab) unsuitable for your application? If you tried it but it didn’t work, we can help troubleshoot.

What country are you in?

Who is your present provider?

NV fax detect hasn’t been a thing for more than a decade. As Stewart says, if you want fax detection your choices are limited to what you see in the GUI.

As I said, I am very new to Freepbx and Asterisk. In any case, if this is the situation, I think the wiki (https://wiki.freepbx.org/display/FPG/Fax+Pro-Admin+Guide#FaxPro-AdminGuide-FaxDetectiontype) should be updated.
However, at this moment, I am having problems with my new VDSL draytek modem (I am changing the router provided by my Internet/VOIP provider which is Vodafone Italia) just to open the pbx to external calls.

As soon as I’ve got things sorted out, I’ll do the necessary tests and report here.

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I believe that a free number from https://www.messagenet.com/voip/ should meet your fax reception needs. (I have not tested them for fax but have no quality issues on voice calls.)

If you get a number from a Voxbone reseller, it will support T.38 and should work fine for fax. Among companies that I’ve dealt with, there are metered IT DIDs from Anveo ($0.90/month + $0.01/minute), AnveoDirect ($1.50/mo. + $0.004/min.) and Voxbeam ($1.50/mo.; 10,000 min. free).


I guess this needs to be updated as well?

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