Field Phone Open Source Production – Demo Vid & Kickstarter


13 responses to “Field Phone Open Source Production – Demo Vid & Kickstarter

  1. Sounds like someone needs to present at an event in North Carolina in 2016.

  2. No way to call phone to phone? How do you know when the other end desires to talk? No ringer voltage capability?

    • Grenadier1

      In the details it says that the notification is accomplished outside of the normal ringer circuit to reduce voltage needs.
      That can easily be done with a small flashing LED that lights in an off-hook condition.

      Please folks support this effort if you can. I think its a great idea.

    • Hi Rocky (and drdog09 below),

      Great questions. Check out the video starting at 10:08 about the ring interface module. The idea was to have a silent (light only) or discreet (piezo buzzer only) ring indication to avoid attracting the attention of zombies. There are also many future options for this feature that are on the drawing board.

      If someone needed a system that did full ring and more or less emulated a real telephone system with all the features, then check the web for telephone line simulators or pick up a used PBX. These are going to cost more and require more power, but will have all the bells and whistles.

      Or, we could make a low power version of a more fully functional telco, but it will cost more than this field phone host module or bundles. It will also have the dreaded S-word (software) in it. If there is sufficient interest, we could put that in the pipeline also.


  3. Nice. But at no time during the demo did I hear a ring tone generated. So how does the other party know when to pick up??

  4. Grenadier1

    Nice to see that idea coming to fruition. Good work.

  5. Gatorbait3014

    This is a very primitive version of what is known as a telephone “Ringdown” circuit. I can do the exact same thing (minus the circuit board with the RJ-11 connectors) with a single 9 Volt battery, which is supplying the required voltage for voice communications, and is known as Talk Battery.

    A proper Ringdown circuit will actually ring the bell/sounder on the 2nd telephone set when the first telephone set is taken off-hook, and are fairly easy to build. What is even simpler for the non-technically inclined, is to just purchase a Ringdown box, already built. Plug and play!

    – Ramsey Electronics manufacturers the Model # QLRD1
    – Viking Electronics manufactures several models. The DLE-200B supports two telephones. Viking Electronics also offers a free PDF document on the subject:
    – Teltone offers their TLS-4 Telephone Line Simulator, which supports four(4) lines.

    Do a bit of research on the internet and find what fits your needs.

    • Hi Gatorbait3014,

      Added your suggestions to the Battery and Resistor Alternatives post on the forum:



    • Grenadier1

      Actually what is even simpler is to support this kickstarter which will give you the basic components to set up a system at your retreat or Observation post and will be providing funds to someone who shares like minded ideas.

    • Hi Gatorbait3014,

      About the ringdown circuit, that is entirely backwards from the intention of the field phone host module concept. An automatic normal ring on the other end could be suicidal (or homicidal, depending on your perspective) if picking up one end caused the other end to ring normally. On a shop floor or other normal situation, ringdown is great. For an OP, ringdown is bad, particularly if the zombies are staggering by at the time. That is why it has an LED or, optionally, a quiet buzzer. The OP can disable the buzzer, yet still see an indication of an attempted call.

      All the devices you mentioned need significant power also (and in specific voltages), but they are great if grid power is available.


  6. Alfred E. Neuman

    Reblogged this on ETC., ETC., & ETC..

  7. Reblogged this on disturbeddeputy and commented:
    Got Coms?

  8. StevenKY

    My mom’s kid brother (Uncle Junior) grew up in North Central Kansas on a farm and had a pal who lived a few miles away. They used a home-brew phone system using the barbed wire fence wiring to make their connection. No metal fence posts back at that time but steel wire stapled to wooden fence posts made for a dandy system to communicate. There is always a way to communicate when needed and the cell phones will die (or be jammed) and the Bell System can be shut down whenever the Poop Hits The Fan but a jury rigged system can be easily overlooked. Culverts under the road can be used to snake a pair of wires to connect to another network of fences to expand the home-brew phone system. Ham radios that have been modified to go “Out-of-Band” are also useful. Just my 2 cents worth.