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  1. Standard member sonhouse
    Fast and Curious
    01 Jul '10 22:53
    I tried to hook up my photosmart all in one printer/copy/fax as a fax machine and it turns out HP does not have the knowhow to connect a 5 khz bandwidth fax signal through a router. Nice, eh. They only work with the old fashioned analog hard wire phone lines.

    Anyone out there know of a fax machine that can work through a router?
  2. 02 Jul '10 06:19
    Originally posted by sonhouse
    I tried to hook up my photosmart all in one printer/copy/fax as a fax machine and it turns out HP does not have the knowhow to connect a 5 khz bandwidth fax signal through a router. Nice, eh. They only work with the old fashioned analog hard wire phone lines.

    Anyone out there know of a fax machine that can work through a router?
    I am not sure what a 5khz fax signal through a router is. But my suggestion would be to find a free fax to email service, then only print the fax when you need hard copy. Save the trees!
  3. Standard member sonhouse
    Fast and Curious
    02 Jul '10 11:16
    Originally posted by twhitehead
    I am not sure what a 5khz fax signal through a router is. But my suggestion would be to find a free fax to email service, then only print the fax when you need hard copy. Save the trees!
    That does seem the only option. The 5 Khz bandwidth describes how much space on the internet dial it takes to send a fax, the internet dial being akin to how much space certain services take on a literal radio or tv dial. Like an AM radio station has a signal that has a big booming carrier, a single frequency that takes up very little space on the dial but the sound of the voices and the music that AM signal takes up goes on either side of that main carrier so it takes up twice as much bandwidth as the actual voice or music needs to get the information across.

    If you want 20 kilohertz, (the upper limit of most people's hearing) or all the sound information in a concert orchestra, you need twice that bandwidth or 40 kilohertz to hear all you can on an AM radio station.

    There is another way, called Single Sideband where one of the AM sidebands is chopped off and you still get the same result, but now it only takes up 20 Kilohertz of the radio dial so now you only need to have a signal that goes from say 1000 Khz on the radio dial to 1020 Kilohertz on the radio dial.

    A regular AM broadcast would cover the frequencies from 980 Khz on that same dial to 1020 Khz so that signal would block out or interfere with a single sideband signal sitting on 980 Khz that would only go to 1000 Khz. So you can have twice as many single sideband signals on a given radio dial than AM.

    So in a fax machine, since it is only words written on paper, you only need a few kilohertz of bandwidth. It doesn't matter it's going over a wire, or satellite radio signal or a fiber optic path, you still have to set aside about 5 khz to do a fax signal and still get the information transmitted in a decently low amount of time.

    You can see if you only could transmit one letter per second, you could do it with a lot less bandwidth which is how the Voyagers can send signals from billions of kilometers out in space, they don't send tv signals, for instance, because you would need a really powerful transmitter on the probe and a really powerful energy source so you instead use a really powerful antenna (concentrates the peanut whistle powered radio signal in a beam aimed at Earth) and that reduces the power needed to get a certain bandwidth to the Earth.

    Then they squeeze out in time a small bandwidth of information spread out over a relatively long period of time so the tiny signal finally reaching Earth can be deciphered and rendered into real scientific information.

    So the same with a fax signal, you want to send letters at a reasonable rate and 5 kilohertz does that just fine, say you need 100 hertz (one hundred pulses per second) to send one letter. Then you can send 50 characters per second with a 5 kilohertz bandwidth. That is a lot faster than you can type.

    Suppose you want to send 500 letters per second, you would need with those same rules of 100 hertz bandwidth per letter, you now need 50 Kilohertz bandwidth to send out that 500 letters per second.

    Does that make sense?
  4. 02 Jul '10 12:14
    Originally posted by sonhouse
    Does that make sense?
    No, not really.
    It is my understanding that fax machines have a standard signaling mechanism that they all use to communicate via the POTS.
    I don't understand where your router comes into the equation, or where your special signalling method comes from.
    You want to receive 5khz fax signal, but who is going to be sending the faxes?
    And I thought email killed off the fax years ago anyway!
  5. Standard member sonhouse
    Fast and Curious
    02 Jul '10 13:28 / 3 edits
    Originally posted by twhitehead
    No, not really.
    It is my understanding that fax machines have a standard signaling mechanism that they all use to communicate via the POTS.
    I don't understand where your router comes into the equation, or where your special signalling method comes from.
    You want to receive 5khz fax signal, but who is going to be sending the faxes?
    And I thought email killed off the fax years ago anyway!
    Are you kidding? Show me a business that uses email fax. That is for home use so you don't have to have a fax machine. It always was rather rare for people to have had fax machines because they were expensive, clunky and slow. For sure email is far superior as far as getting information from point a to point b. But for businesses where they want a physical paper without the hassle of converting email to print, you can't beat a fax machine.

    Sorry you don't understand bandwidth, I don't think I can explain it any more concisely, it just takes a certain amount for any given kind of information and you can spread that out over time so the same info gets there but takes longer, that uses less bandwidth (Bandwidth=the # of Hertz or Kilohertz you need to do that).

    For instance, I have a document I need to sign and send back to the sender, a fax does that nicely. An Email document means I have to print it anyway, sign it, scan it in, type in the address, put something in the subject line, send it to the email outbox, THEN send it to the recipient. A fax does that in one go.

    Fax over the internet is a bit simpler than that at least but I still have to print the doc, sign it, scan it in, enter the phone #, and hit send. A real fax machine is easier.
  6. 02 Jul '10 15:03
    Originally posted by sonhouse
    Are you kidding?
    Only partly.
    The use of faxes dropped dramatically due to email. Especially in places like Zambia where international faxing is expensive.

    Show me a business that uses email fax.
    Our company does. I admit there is one fax/printer at the head office, but the Chief Accountant (branch office) uses only email-fax despite having at least 3 fax capable printers.

    That is for home use so you don't have to have a fax machine.
    My mum uses a fax modem for home use. But she has also used email-fax in order to have a US fax number.

    Sorry you don't understand bandwidth,
    What I really don't understand is how you expect to receive a fax by any means other than from another fax machine and a phone line.

    For instance, I have a document I need to sign and send back to the sender, a fax does that nicely. An Email document means I have to print it anyway, sign it, scan it in, type in the address, put something in the subject line, send it to the email outbox, THEN send it to the recipient. A fax does that in one go.

    Fax over the internet is a bit simpler than that at least but I still have to print the doc, sign it, scan it in, enter the phone #, and hit send. A real fax machine is easier.

    Thats because you haven't figured out that:
    1. You can simply scan your signature once then paste it into any email faxes you receive and send it straight back. (save the trees). My mum does this a lot, and she is not unique.
    2. A fax of a signature holds no real value whatsoever. It is trivial to forge and thus the 'copy proof' concept of a signature is lost. If you hold onto the original then it might have some value, but I still find the value of the faxed copy to be minimal.
  7. Standard member sonhouse
    Fast and Curious
    02 Jul '10 16:15 / 1 edit
    Originally posted by twhitehead
    Only partly.
    The use of faxes dropped dramatically due to email. Especially in places like Zambia where international faxing is expensive.

    [b]Show me a business that uses email fax.

    Our company does. I admit there is one fax/printer at the head office, but the Chief Accountant (branch office) uses only email-fax despite having at least 3 fax capa then it might have some value, but I still find the value of the faxed copy to be minimal.[/b]
    The bandwidth issue is identical whether over hard lines or radio or fiber optic cables, it doesn't matter the media, it all comes down to bandwidth and how many letters you can cram down some media in one second, more letters per second, more bandwidth needed, no matter what you use.

    That point about scanning in your signature, I hadn't thought of, thanks for that tip.
    Here in the US, business fax machines are still # 1 in offices but of course that will change over time. I'm all for saving trees. My wife just got a Kindle for reading. I am still stuck in the tree killing phase of reading

    The part about sending a fax over anything but a hard wire phone line is just a matter of engineering. It is entirely possible to make a box or even a PCI card that takes in fax signals, digitizes them and at the other end, if you have the same PCI card, your fax machine could be hooked up to that and no hard wire needed. Save the trees! I haven't seen such a card yet but it certainly can be done.
  8. 02 Jul '10 16:20
    Originally posted by sonhouse
    The bandwidth issue is identical whether over hard lines or radio or fiber optic cables, it doesn't matter the media, it all comes down to bandwidth and how many letters you can cram down some media in one second, more letters per second, more bandwidth needed, no matter what you use.
    But where will the fax signal be coming from?
  9. Standard member sonhouse
    Fast and Curious
    02 Jul '10 18:12
    Originally posted by twhitehead
    But where will the fax signal be coming from?
    Just like any other originator of signals, on a radio station its the transmitter site, where you see all those huge AM towers. On a computer, it generates signals that can easily be picked up by a short wave radio, in fact they are very annoying to us hams because they cause all kinds of interference even though they are supposed to be confining their signals to hard wires or optical cables, they are electrical before they hit the fiber and so some of it leaks out into the world, right into my ham and shortwave receivers.

    A fax machine is no different, it has a circuit board that generates those kind of signals also but at a much lower frequency so you would be hard pressed to actually hear those signals in a shortwave radio.

    I will have to try that experiment to see if I can hear them over a radio! I did that with some digital watches and you wouldn't think they would give a signal capable of being picked up by a radio but they do!

    Only within a few inches of the radio that has a built in antenna but it is there nonetheless! So that is on my experiment plate, see what I hear on a shortwave or AM radio when the fax is being sent.

    But that signal then goes to the wires of the phone company and is sent down the line to another fax machine that just takes the signal in reverse and applies it to the printer section.

    It is like a slow scan tv signal, the old fashioned analog tv's. A beam of electrons would sweep across the screen back and forth and another signal inside the tube would force that beam to move up and down at the same time so the action of the two signals causes the electron beam to sweep across from the top, then down a tiny bit and another sweep and so forth to the bottom of the screen then the cycle starts over at the top of the picture tube.

    It's like that with a fax, kind of like how you would take a piece of paper and hold it over some sculpture or other and run a pencil over the paper which gives an impression of what is underneath.

    Instead of a pencil, its a narrow beam of light, maybe even a laser in the newer ones but it does a back and forth scan and a light sensor picks up the variations in brightness, meanwhile the paper moves down a bit and the next scan starts and so forth till the end of the page.

    So what is transmitted as the fax signal is just a stream of information about the brightness of that light beam, a single scan doesn't have much information in it till a bunch of scans has gone by and revealed what letters are to be sent.

    That is an analog signal, not digital. It is easy to digitize such signals however.
    You feed the analog signal into an analog to digital converter and a no light signal may be represented by all zeros, 00000000, say in this case an 8 bit stream, and the max signal as 1111111 which the other end would integrate all the ones and zero's and put them in the proper order to recreate the letters of the fax.

    That's how it COULD be done but is not, fax is just an analog signal to an analog receiver at the other end.
  10. 03 Jul '10 07:44
    Originally posted by sonhouse
    That's how it COULD be done but is not, fax is just an analog signal to an analog receiver at the other end.
    And you are still not answering my question.
    You want a fax machine that works different from the one you bought.
    Where do you expect to receive faxes from? If it is from another fax machine, then what will convert the signal to the one you want, and why?
  11. 03 Jul '10 12:17
    Buy a scanner, scan your documents and email them. Nobody uses fax machines anymore, they died out when broadband came about.
  12. 03 Jul '10 13:49
    Originally posted by Starrman
    Buy a scanner, scan your documents and email them. Nobody uses fax machines anymore, they died out when broadband came about.
    I am not trying to be rude or trying to be difficult or anything, I have far to much respect for you for that. I simply want to understand what you are getting at.
    1. You want a fax machine that works differently from the HP one you bought.
    2. All other fax machines that I know of, only know how to communicate with the ones like the HP one you bought.
    3. I don't understand what you want to do with your custom fax machine.
    4. Or I don't understand what your initial query was.
  13. Standard member sonhouse
    Fast and Curious
    05 Jul '10 16:41
    Originally posted by twhitehead
    And you are still not answering my question.
    You want a fax machine that works different from the one you bought.
    Where do you expect to receive faxes from? If it is from another fax machine, then what will convert the signal to the one you want, and why?
    At the time I bought this all in one printer that had a fax feature, I was using regular AT&T hard wire phone lines. Then a year later, we found out our IP started a new service VOIP, so we switched and saved about 25 bucks a month. A few months later I went to send a fax like I had for years before and it didn't work.

    I contacted the IP and they said they were working on a fix in engineering but it wasn't ready yet. So I contacted HP support only to be informed that fax machines don't work with digital phone lines like I had. So I was stuck between a rock and a hard place.

    That's why I asked if anyone knew of a solution. The only solution seems to be as Starmann says, scan and email. It appears so far that is the only option till the IP engineers make a solution if they indeed can. It's obvious there can be a PCI card made that would do the job but it is unlikely for anyone to make it, so the IP dudes would have to do it internally to their system.
  14. 05 Jul '10 17:52
    Originally posted by sonhouse
    .....we found out our IP started a new service VOIP, so we switched and saved about 25 bucks a month.
    Now I understand. You have a voip phone and need to send and receive faxes.
    I currently have a voip phone and have been playing around with it for a year or so. We use them to communicate within the company (between cities) at the cost of the internet usage. We also use them to receive calls on US and UK numbers and to make free calls to the US via Google voice.
    Today I was downloading Asterisk - a voip PABX as we plan to move the whole company over to voip in the near future and its my job to make it happen.

    I can tell you straight away, that one solution is to put a hardware device that has an outgoing phone line into an asterisk server, then you can receive faxes to that line (which you plug into the fax machine). Hardly a cheap or simple solution.

    You can also set up an asterisk server to receive faxes and convert them to pdf and email them to you - basically your own fax to email service. Again, over kill for a home user as you can probably get the service on the internet for free.

    Now all I need to do is find someone who has taken it a step further and added the ability to automatically print the fax instead.

    Faxing out from the scanner would be a bit different. I need to think about it.
  15. Standard member sonhouse
    Fast and Curious
    05 Jul '10 18:11
    Originally posted by twhitehead
    Now I understand. You have a voip phone and need to send and receive faxes.
    I currently have a voip phone and have been playing around with it for a year or so. We use them to communicate within the company (between cities) at the cost of the internet usage. We also use them to receive calls on US and UK numbers and to make free calls to the US via Googl ...[text shortened]... fax instead.

    Faxing out from the scanner would be a bit different. I need to think about it.
    Our service is from a Linksys wireless router which has two phone lines added, so we plug the phone into that. When I said a PCI card could be engineered to handle fax signals I was unaware a solution of sorts had been worked out in your asterisk thing. Do you know how much such a beast costs?