Problems using a cellular modem to send faxes

Crashnburn

Crashnburn

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Crashnburn
A while ago, I converted my Mother In Laws (MIL) cable internet and fax to a T-Mobile compatible cellular modem to eliminate Xfinity's (ComCast) ever increasing rates.

She has a cellular modem feeding a wireless modem, so her computer, fax, TV, etc., can get internet w/o cables. Internet and TV work fine, not so much the FAX.

Her fax worked fine when connected to the cable, but it has never worked since. She bought the All-In-One (Fax, Printer, Scanner, etc.) at Best Buy, and had a couple of crews come out to trouble shoot. The best they could come up with was a lack of signal strength. But, they didn't have a solution for increasing signal strength.

I got the idea for a Cellular Phone Booster here on POA, and installed a tri-band booster( she lives in a virtual Faraday Cage (metal framed house)) to increase signal strength. I put the Yagi antenna too close to the interior antenna, but still boosted the cell phone signal by a bar. If it's not too hard to relocate the Yagi, I have lots of cable to move it farther away. The fax is connected through a wireless modem. My next experiment is to directly connect it with an Ethernet cable to the cellular modem.

The fax still doesn't work. We can here it dialing, and sending a sync signal, but then nothing, and we get a communication error page after it fails.

She lives an hour from me. I'm returning tomorrow. Has anyone else tried using a cellular modem to transmit faxes? Did you run into any problems, and if so, what was/were the solution(s)?

Thanks,
 
A fax converts the image into an audio signal to transmit over the phone line, but a cell phone compresses the audio into a digital signal to save bandwidth, and thus scrambles the fax data. You can't use a fax with a VOIP phone line, either. It's not a signal strength problem.

But who sends faxes any more anyway? Take a picture of the document and send it via email or text message.
 
Seriously. I don't think our fax number is even active anymore, since we went VOIP. Even most cheap home printers have scan to PDF capability.
 
Sign up for a email-to-fax gateway service.

Actually, I should add "if they still exist". Even those may have already gone obsolete by now.
 
Funny.

We have a fax function on two of our copiers.

It has been, probably, two months since the last fax came. I even stopped getting the advertisements for residential roof contractors.
 
Well, my MIL has to send documents (sometimes 25 pages or more) to institutions that don't accept email.

Thanks for the explanation for why you can't fax over a cellular modem. But, why can we do internet over cellular modem?

Thanks for the email to fax service idea. I'll check to see if I can find one.

Actually, I found several, as well as some web portal services. They are all significantly less than a dedicated line.
 
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I had a financial institution ask me to send a fax to them last year. I just told them: "Sorry, I can't - because I live in 2019". Then went somewhere else instead.
 
I work for the federal government, and even we don't use fax anymore. We still have one, collecting dust.
 
Crashnburn said:
Thanks for the explanation for why you can't fax over a cellular modem. But, why can we do internet over cellular modem?
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Internet is using the cell modem's 3G or 4G protocol, which the cell service knows how to handle. Fax is data converted to audio because that's all that was available in 1980, the cell phone thinks it's a voice call so it compresses it, filtering out the frequencies the human ear can't hear anyway... but the fax uses those frequencies.
 
it wouldn’t work even without the compression. The modem is using the same frequencies to send the data as a fax does. The modem on the other side would interpret the fax signal as a modem signal and be very confused.

https://app.hellofax.com/
 
Weekend Warrior said:
I work for the federal government, and even we don't use fax anymore. We still have one, collecting dust.
Click to expand...

The only widespread use of fax machines that I know of, is the medical community. They (and I) have never heard of a fax being intercepted or altered. -Skip
 
Fax is somehow intolerant to some of the compression codecs used by VoIP. I had to work with our VoIP vendor to change the settings for our fax line to make it work. I don't recall what exactly we needed to change. Also, older fax machines seem to be more tolerant to the VoIP issue than newer ones.
 
I couldn't get my fax to work on Ooma but it works well on Google voice with an Obi device.

At least for the OP, T-Mobile cellular service is an option for home internet service. I have a cabin in Gatlinburg in a dead zone with no option other than satellite internet.
 
Dana said:
You can't use a fax with a VOIP phone line, either.
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not entirely true..... but close.
My wife is in the medical field and she still uses fax. It takes some time on with the provider's tech people to adjust some settings...but it can be done. Unfortunately I'm not expert enough to walk anyone through it.
I suspect that it might be possible over cellular, but probably less likely is my guess
I'd look at something like efax if it were me
 
I think you're going to have to go to scan to pdf, then use an online service to Fax. The cellular network is digital data packets. The modem just sends and receives the data packets. The voice call converts (at the phone) audio to data packets and vice versa. A Fax converts the scanned document to audio, which the phone then converts to digital data. That's where it gets scrambled.

Here's an article rating online fax services: https://www.techradar.com/best/best-online-fax-service

Many medical organizations still use Fax because they avoid some of the complications of digital protection in the era of HIPPA by isolating their networks from any outside contact.
 
jsstevens said:
I think you're going to have to go to scan to pdf, then use an online service to Fax. The cellular network is digital data packets. The modem just sends and receives the data packets. The voice call converts (at the phone) audio to data packets and vice versa. A Fax converts the scanned document to audio, which the phone then converts to digital data. That's where it gets scrambled.

Here's an article rating online fax services: https://www.techradar.com/best/best-online-fax-service

Many medical organizations still use Fax because they avoid some of the complications of digital protection in the era of HIPPA by isolating their networks from any outside contact.
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Thank you.
The places my MIL has to deal with are in Northern CA, around Oregon House, and they aren't close to being up to date.

I was hoping someone would rate email to fax services because my MIL doesn't do computers very well and I can't be around to hold her hand after I get it set up.
 
Crashnburn said:
I was hoping someone would rate email to fax services because my MIL doesn't do computers very well and I can't be around to hold her hand after I get it set up.
Click to expand...

Years ago I worked remotely and the employer insisted on receiving weekly faxed equipment inventories. I was not about to buy a fax machine for their foolishness so I used eFax instead. It worked well. I simply "printed" my Excel spreadsheet to a PDF and attached it to an email. The employer was none the wiser.
 
Fax over anything but POTS lines is a pain. We get them to work over our VOIP system but it is never straight forward and sometimes just doesn't work and we end up using a POTS line. Too many conversions, compression and other things that get in the way.
 
Skip Miller said:
The only widespread use of fax machines that I know of, is the medical community. They (and I) have never heard of a fax being intercepted or altered. -Skip
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Internal Revenue Service. Fax or mail. Won't take email.

Although they use some sort of e-fax and it is unbelievable how many times "it is down."
 
Doug Reid said:
Get a cheap dedicated land line...caseclosed.
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We’re stuck with ComCast; who have a monopoly in the area; and they are continually raising their rates, so we thought we could escape them by going cellular.

An update. The Fax was connected to the sprint phone instead of the T-Mobile modem. I tried connecting an RJ45 cable between the fax and the T-Mobile modem, and still no joy.

I researched email to fax and I like HelloFax the best I did a test fax to our house and it worked fine. Now to bring my MIL into the 20th Century (I know it’s the 21st).
 
For one office I got a POTS line for fax and alarm system. One day I get a call 'the fax don't work'. Turns out Verizon had changed all the POTS lines in the building to a VoIP box hooked to their fiber :-(
 
Skip Miller said:
The only widespread use of fax machines that I know of, is the medical community. They (and I) have never heard of a fax being intercepted or altered. -Skip
Click to expand...

They wear our fax machines out still at our facility. Mostly the healthcare division, but also still some other use.
This even after implementing very simple to use encrypted email options.
One of our pharmacies actually provides multiple fax machines as they prefer using them.

sorry for the thread drift... we still use POTS on one of our faxes, and PBX lines for the others.

Really seems out of whack now that we've moved mostly to EHR. Now they scan the fax to .pdf and upload to the software.
 
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Any voip circuit thats using G.711 without compression (or packet loss — fix your crappy network) will happily carry fax traffic.
 
denverpilot said:
Any voip circuit thats using G.711 without compression (or packet loss — fix your crappy network) will happily carry fax traffic.
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Thanks. Unfortunately, the crappy network is Sprint, and they don't listen to me. I called Comcast. We'll get a voice only line, then a Xfinity certified voice and data modem that supports DOCSIS 3.0/3.1 and that should solve the problem. That will happen in June, after the Sprint contract expires.
 
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Run into the scenario two or three times a year with things will only be accepted over fax...no emailed PDFs...theory being that the data in a fax its essentially encrypted then no longer exists digitally once received vs an email that is forever stored on a server somewhere and subject to data breach...but I just end up using eFax or similar service when needed (which has a basic free option depending on needs)

But I do have a hard fax that still works over VOIP line....guess it all depends on carrier and equipment.
 
Crashnburn said:
Thanks. Unfortunately, the crappy network is Sprint, and they don't listen to me. I called Comcast. We'll get a voice only line, then a Xfinity certified voice and data modem that supports DOCSIS 3.0/3.1 and that should solve the problem. That will happen in June, after the Sprint contract expires.
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I believe Xfinity uses G.729 or something other lossy compression types sometimes. Make sure they’re providing a line that has NO compression. G.711 or it won’t work.
 
I remember the good old days when digital cellular just came out and the device that hooked the fax to the phone was actually itself a fax modem, so it acted as a fake fax, turned the audio back into fax bits, sent it over the cell network to a central fax modem somewhere which actually dialed the PSTN number for the destination fax and turned the bits back into audio. Talk about extra steps. I believe the same device could also be used for data modems like credit card terminals.

I'm also a little surprised no service provider offers a fax machine that looks like normal but just has an internet connection that does the same through some central bank of fax modems somewhere so you get the normal fax machine interface and it just skips the audio bit. Hmm, I guess there is: https://www.mfax.io/faxbridge bring your own fax machine. Looks like there's a whole class of 'Fax Gateways' that let you use a fax with a box over IP to a service that does the faxing without worrying about VOIP codecs. Which, oddly, are exactly like I described the old days with cellular service.
 
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chartbundle said:
I'm also a little surprised no service provider offers a fax machine that looks like normal but just has an internet connection that does the same through some central bank of fax modems somewhere so you get the normal fax machine interface and it just skips the audio bit.
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Sending images of documents in the modern era over modems is stupid, but fax machines are kept on life support because regulators (inaccurately) think they’re more secure than alternatives.

Writing a script to make a PC scan a document with a scanner and act like an appliance to send documents is easy. It’s the transmission protocol the regulators want.

Tons of cloud fax services out there. Almost all owned by j3. MetroFax, eFax, SFax, etc... all owned by the same company.

If there ever was an anti-trust suit begging to happen, they’re it. But nobody really cares. Not enough money in it.

All use the supposedly insecure data transfer methods to send and receive right to the very last delivery to a doctor or lawyer’s office just to avoid HIPAA or give a document some fake regulatory form of legal legitimacy.

Shoving a RaspberryPi inside a scanner and having it send files to places in a secure way, is easy. The problem is, it becomes a networked machine that has to be audited for security. Those audits run over $50,000 and are sometimes mandated quarterly.

Which is why we do over $5000/mo in business with a j3 “faxing” company. Nothing to audit. Keep the browsers our users access it all with updated, and that’s it.

Plus we’d turn physical fax machines into smoking piles of junk at our volumes. We’d need a room full of them going 24/7.

At the low volume end of things, like a single docs office, a $500 investment in even a fancy fax machine saves them the same $50,000 a quarter. Once they’re blowing up a machine per quarter from heavy use, then the cloud service makes more sense, cost wise.
 
denverpilot said:
At the low volume end of things, like a single docs office, a $500 investment in even a fancy fax machine saves them the same $50,000 a quarter. Once they’re blowing up a machine per quarter from heavy use, then the cloud service makes more sense, cost wise.
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Except that most doc offices have audit requirements anyway thanks to electronic medical records. They need to enter stuff into a computer to send to the data warehouse. And most are now using it to keep charts and take notes - no paper. And most places don't use paper script any more - the script is sent to the pharmacy via computer program. For security. Auditing a piece of fax software is trivial compared to the rest of the stuff.

I recall walking into one MD's office a few nears ago and seeing a ransomware screen on someone's laptop. That's what we've come to. "But it's more efficient and secure and safer for the patient". Yeah, right. But it does make surveillance easier.
 
denverpilot said:
Which is why we do over $5000/mo in business with a j3 “faxing” company. Nothing to audit. Keep the browsers our users access it all with updated, and that’s it.

Plus we’d turn physical fax machines into smoking piles of junk at our volumes. We’d need a room full of them going 24/7.
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Ahhhh... So you are the dude who was always robodialing my fax with exclusive one-time-only insider real estate deals!

Sorry I never got back to you on that.
 
smv said:
Ahhhh... So you are the dude who was always robodialing my fax with exclusive one-time-only insider real estate deals!

Sorry I never got back to you on that.
Click to expand...

LOL hell no. I refuse to build outbound call centers or fax spam systems — unless I get really really desperate.

Probably not even then! LOL.
 
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chartbundle said:
I remember the good old days when digital cellular just came out and the device that hooked the fax to the phone was actually itself a fax modem, so it acted as a fake fax, turned the audio back into fax bits, sent it over the cell network to a central fax modem somewhere which actually dialed the PSTN number for the destination fax and turned the bits back into audio. Talk about extra steps. I believe the same device could also be used for data modems like credit card terminals.

I'm also a little surprised no service provider offers a fax machine that looks like normal but just has an internet connection that does the same through some central bank of fax modems somewhere so you get the normal fax machine interface and it just skips the audio bit. Hmm, I guess there is: https://www.mfax.io/faxbridge bring your own fax machine. Looks like there's a whole class of 'Fax Gateways' that let you use a fax with a box over IP to a service that does the faxing without worrying about VOIP codecs. Which, oddly, are exactly like I described the old days with cellular service.
Click to expand...
Awesome!!!! Thank you. That will save a ton of inconvenience!!

I looked into this a little more. Besides the unit, there’s a $9 monthly charge, for up to 250 sheets per month, to use the account. That’s a bit more than the Xfinity voice compatible 3.0 modem, and the current delta between Sprint and Comcast.

Also there would be another box to bug my MIL and she hates extra electronic boxes. The Xfinity box would replace the Sprint box.
 
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