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Magicjack Panasonic NO dial out Fixed

My Panasonic KX-TC1871b will not dial out with Magicjack.
It works fine on a regular landline and also works fine with Time Warner VOIP.
The Panasonic cordless phone started this no dial out problem with the December 2008 Magicjack upgrade.
I have a fix for this no dial out problem.
I did some testing compaired to a corded phone by recording the DTMF output tones on each unit.
When i play back the Panasonic DTMF dial tones into the mouth piece of the corded phone it dials out perfectly and makes the call.
When i play back the corded phone DTMF dial tones into the mouth piece of the Panasonic cordless phone it does not dial.
This proves that it is not a problem with the DTMF output duration as others have said.
Comparing the audio output level between the corded phone and the panasonic cordless, I found the audio level of the Panasonic cordless to be a little less than half the voltage VP-P output of the corded phone.
In conclusion the audio output of the panasonic cordless phone is too low to trigger the DTMF on the Magicjack.
Here is what i did to fix this problem. (lucky me) i have the Service manual for this phone.

Click image to see full size
Notice the component circled in blue. it is labled C433 8.2k.
The parts list says this component is an 100p capacitor.
Upon inspection this is not a capacitor at all, must have been a mis-print or an update.
it is a 8.2k ohm resistor.
Simple fix, increase the current to the base of Q131, but no too much.
I opted to make it variable using a trimmer pot.
This is what i used.
A 5.6k ohm 1/8 watt resistor im series with a 10k ohm variable resistor and a switch to take it out of circuit.

r1 is the total resistance of the above diagram
r2 is the resistance of component c433

Click image to see full size
Connect the wires from the constructed circuit to the solder points marked in red on the above diagram.

NOTICE: The circuit works fine set to full resistance on the trimmer pot. I am not even going to turn the voltage up with the trimmer..
I suggest you only need to use a 16k ohm resistor in place of the circuit i described, the switch is optional.

This modification works perfectly for this phone and the same scenario should work for any other phone with the same problem.

Fine Print:
Use this mod at your own risk, don't blame me if you blow up your phone or magicjack. It might be a good idea to get a qualified electronics technician to do this for you,

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February 19, 2018