OBi202 + OBiBT + Smartphone WITHOUT VOIP provider = FAX ??

[Simon00]

I'm wondering if it is possible to connect a FAX machine to one of the ports on an OBi202 + OBiBT, and FAX thru using my unlimited cellular voice plan without using any VOIP provider?  

I am at places where there is no internet service or they charge way too much.. I also do not wish to use fax service providers for documents w/ confidential personal info. of clients.

[Shale]

I have never used OBiBT, but I think that would work. I successfully faxed via my OBi202 via GV as as a test. I did not try adjusting the fax machine settings. If you had a problem, you could set the fax machine to use a slower speed, but I doubt that will be needed.

[Simon00]

I find that Google Voice is not very reliable for FAX, and thought that if I can interface my unlimited Smartphone voice plan using OBiBT + OBi202 + regular FAX machine, it'll be perfect.

No one has tested this??

[Clive]

Hi guys, if you check, the op is wanting to fax through the obi202>obibt>cell phone data plan, NOT via google voice or any other voip service.

The question that needs answering is, can the fax go from the fax machine into the obi202, then out via obibt where it is then passed to the cell phone for transmission.

[Simon00]

Hi Clive,

That is EXACTLY what I'm trying to do...  I'd REALLY like to know if it works before buying the two items together and telling friends & relatives to buy them as well.  I'd REALLY APPRECIATED it if someone who has an OBi202 + OBiBT and test it w/ their Smartphone voice plan and give some feedback?  Much appreciated!!

Thanks!

[drgeoff]

Hi guys, if you check, the op is wanting to fax through the obi202>obibt>cell phone data plan, NOT via google voice or any other voip service.

The question that needs answering is, can the fax go from the fax machine into the obi202, then out via obibt where it is then passed to the cell phone for transmission.

It may not impact on the question that needs answering but is "fax through the obi202>obibt>cell phone data plan" entirely accurate.  I've never used an OBiBT (I have a 110) but I had envisaged that calls via OBiBT use voice not data mode on the cell phone.  Can someone who knows please confirm or refute?

[Simon00]

Though Bluetooth has a specific Fax Profile, which will only work thru a PC w/ BT connected to a BT cell phone.  It is neither voice or data... some kind of Hayes AT modem command set.  I remember seeing it in the Edge or the before/older than Edge networks, where you'd connect a 9-pin serial cable to your laptop PC from the phone and then put phone into dial-up Modem-mode. You'd get 14.4Kbps if your lucky... And fax works quite reliable at 9600 baud.

However, if I'm using the Smartphone's data plan, I might as well get the ObiWiFi + Obi202, instead and turn ON Smartphone Hotspot and use it the regular way w/ a GV or another VOIP account to fax.

I'm referring to using the Voice feature of my Smartphone to have the OBi202 + OBiBT FAX out a document using a regular HP or Brother fax machine.

Any info. regarding this feature is GREATLY appreciated!!

Thanx...

[Davoice]

Short version... No.

Longer version...

Technically GSM supported fax but through a special profile.  You have to make a circuit switched connection - which is a 9600 baud connection over the cellular network.  Most modern GSM handsets do not have this feature enabled because we all use LTE, UMTS, HSPA, etc.  Back in the day (mid-90s), I used to have to do circuit switched connections over cellular to dial into various PBXes and work on them. Connecting to the GSM handset for that purpose requires some specialized hardware - that is proprietary to each different phone and not made for modern handsets. The easiest way to connect a fax machine would be through a tellular unit - which is basically a GSM phone in a box with an RJ-11 jack on it... that's if you could find a provider that would give you a circuit switched connection.  The new HSPA and LTE base stations don't support it.  So you'd have to be on an OLD GSM network for it to work.

If you go look at the specs for the Verizon Wireless Home Phone Connect and similar units from AT&T, you will see that those boxes (which have RJ-11 jacks) specifically do NOT support fax machines.

The reason that you can't connect a fax to any new cell phone and have it work is a matter of compression.  The codecs used on your phone are heavily optimized for voice. They aren't made for dealing with the blips and burps made by your fax machine or a dial-up modem. That's the same reason that you can't send a fax over VoIP using a lossy codec like G.729.

So effectively, the answer is you can't do what you think you want to do.  You're either going to have to suck it up and pay more to use a traditional phone line and fax, or you're going to have to suck up your (faux) security concerns and get over the idea of using a 3rd party fax service.

}Davoice

[Davoice]

BTW... one addendum... this one is filled with IFs though...

1) IF you could turn your phone into a wireless hotspot and
2) IF you could connect an OBi202 to the phone's hotspot via ObiWiFI and
3) IF you had a VoIP provider who fully supports T.38 entered as an SP on your Obi202 and
4) IF you had a good enough data connection on your cell phone (i.e. LTE or HSPA+, 3G would NOT work) and
5) IF you configured the fax machine to ONLY use 9600 baud faxing and
6) IF you enabled ECM (error correcting mode) on the fax machine

THEN this might work... most of the time.  The biggest challenge in all those ifs is getting a good enough data connection.  In low signal areas, it likely wouldn't work at all since the VoIP throughput wouldn't be consistent enough. Second biggest challenge is finding a new fax machine that will let you disable 33.6 and 14.4 faxing. Some new fax machines call this "VoIP mode" because limiting them to 9600/4800/2400 baud faxing (the old Group 3 V.27/V.29 fax standard) makes then work better with G.711 and T.38. Anything faster than V.29 will usually cause problems with VoIP. If you can find an old fax machine - maybe something that uses thermal paper to print - you'll have better luck in this scenario than you would with a new fax machine (or your laptop's modem).

}Davoice

[Davoice]

One last note... for those who wonder why it's so hard to get a current cell phone that supports circuit switched calls... the sunset of 2G networks began in 2011. As of 2012, carriers began doing away with full 2G feature support in new base station installs, moving 2G support to less preferred frequencies, and reducing the spectrum allocated to 2G services.

You can learn more about the 2G sunset here:
http://www.telguard.com/2GSunset/Overview

Basically, by 2016, you will no longer be able to use 2G features on the base stations of most major carriers here in the US.  This is why alarm companies, ATM companies, OnStar, etc. are having to replace the old cellular modems in wireless enabled equipment.

[Simon00]

I guess we are ALL going to be moving to a mostly IP-based future for all of our communications needs....

Thank You! VERY MUCH for the detailed explanation....

[Ostracus]

I think we all learned something.

[george.brasil]

Entra nesse serviço FAX - Google Voice

simonics.com