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How to make free calls from a landline phone, cellular

To do this, you need a cell phone, you can disconnect, or beeper. In a cell phone, you need to put the tone mode sound of the keyboard, and the beeper can be collected on a single chip.

Lift the handset on the payphone, bring the speaker of the beeper or cellular phone to the microphone of the handset and dial the number of the desired subscriber (without pressing the call on the beeper or cellular phone), if unsuccessful, reset the machine and repeat. Everything can be freely, not limited to speak.

You can practice at home on your phone. The cell phone should “pick” as loud as possible, some phones work very quietly. It is better to type evenly, with short taps.   In our city, it takes place on half of the machines, since suitable only machines connected to lines with the possibility of tone dialing. The conversation, if not strange, can last more than one minute.


Personally, when I didn’t have a home phone, for almost a year I used the Internet through an automatic machine, connecting from the roof through a ventilation pipe with a three-core cable with the possibility of disconnecting potatoes. The truth was one inconvenience that the PBX once every about three minutes, gives a tone signal to the line.


And if this does not work, then you can add units of the old card (charge it) or make a card simulator (gold card).

Posted by: Pozitron

Read more on the cards:

Principle of work >>     Reading >>    Emulators >>      Another emulator scheme >>

2. How to call home from a cell phone for free.

The principle of operation is based on the deception of the line state detector (DSL), which, as you know, is installed on the PBX and registers the voltage drop on the line. As you know, DSL has its drawbacks more precisely technological gap. Voltage in the line when the tube is lowered is from 50 to 60 volts, if you pick up the tube, the voltage drops to 5-15 volts.

Imagine that someone calls to you, your phone rings, but the caller starts paying for the conversation only when you pick up the phone. Before you pick up the tube, the real connection is established, but the DSL thinks that the tube is not picked up. If you pick up the phone the voltage drops DSL registers and the countdown begins.

Based on this, we must make DSL think that the handset is not lifted. This can be done if the voltage is left high, using a technological gap.


How to call for free from a cell phone.

This device consists of:

  1. variable resistor 5 com power 0.5 watt
  2. condenser 0.5-1 mKf (160 volts)

The circuit is assembled in a socket or in a TA case. Adjustment is as follows:

  1. Take the tube and put the resistor in the extreme left position. (with the maximum TA voltage, the switch is open)
  2. When the resistor knob is rotated, the beep level will decrease and soon the PBX will “twitch” (at this time a beep is heard in the handset with clicks, which then disappears, then appears, the DSL does not determine if the handset is picked up)
  3. Slightly increase the resistance (silence in the tube ... ..)
  4. We take a mobile phone and call to our home, looking at the counter of the mobile phone, if 000 when picking up the phone, then everything is fine
  5. And if not, then we increase the resistance.
  6. Capacitor is used for the passage of conversational current
  7. The switch in the closed state disables the scheme and allows you to dial the number in the normal mode


I have assembled several such devices, the first one I tried on the ERICSON PBX, AX-10 Nikola Tesla patent. (works perfectly), cellular GSM. On other PBXs it also works (unfortunately, I don’t know the types and brands of PBX), but the cellular operator has remained unchanged. The lack of construction of a low signal volume on the TA, I tried the Panaphone KX-5000D telephone first, (it works, but I use the ULF). The most good results on the JACOBS device After that I tried SANYO, etc. The volume is higher, but if you repeat the final stage or increase the sound in the handset will work normally. The call time is limited by 3-4 minutes. You can call again and talk as much as you like. (for starters, you can call to yourself, check the time and find out the duration of free calls). Does not work if AON, H is connected in parallel On modern PBXs   does not work. When the switch is opened, the outgoing number cannot be dialed.