AN DATA OUTPUT FOR DANITA 640
As you might known is the reception to the FM detector optimal, because no distortion exists by the LF amplifiers or any filters etc.
When Danita 640 then saves the reasonable receive when you connect the modem to the FM detector relative to the normal LF output on the back of the transceiver.
THERE FOR I HAVE CHANGED THE FOLLOWING
The detector of the Danita consists the MC3357, which you can find on the component side of the main board, approximately in the middle of the front side of the device back.
The demodulated signal is to pick up from leg 14 of this IC directly.
I have a thread drawn from this leg 14, and these connected to the core of the PA output on the back of the tranceiver.
I have of course the coil that also depends on the exit where normally the LF signal from the PA speaker is offered removed.
So take the opportunity here to PA system will be canceled.
The switch on the front side CB / PA, you can then also use it for something else.
Instead of the LF output on the back, you can now use the PA output on the same back. You can still join the frequency monitors also.
WHERE, HOWEVER, POINTS TO CHECK
The input impedance of the used TNCs can be different, if this impedance is too low, less than about 5K treed distortion of the detected signal by the LF where quality can be used instead of better.
Even worse I use a TNC2S, and this is at the entrance of the TNC a 10K resistor, so that the impedance is always good.
If you are not sure if the impedance of the TNC you are using is highly resistive, make sure that you have a resistance of about 10K record in Danita, among landscaped by you wire running to the PA output.
It may be a little experiment with the value of this resistor, as it is in some cases, at the entrance of the TNC has become the low level.
The level of the detector output of the Danita is in any case was high up, so that it is always made to work.
The TNC2S works at least without series resistance excellent.
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