Accessing the discriminator output on the FRG9600

The discriminator output is needed if you want to decode digital data, 
like the POCSAG code used by common beepers. On this output you have 
raw audio, before it passes through the amplifier, tone control etc. 

This audio will not be affected by volume and tone control, but it will
be affected by the squelch control.

What you need: 1 Capacitor 0,1 uF, a piece of coaxial cable, soldering
equipment.

First write down all the stored frequencies, in case the memories of the
receiver get lost. Then turn it off and disconnect all cables.

Disconnect all cables from the back panel.

Open the top of the FRG9600.

Locate the Narrow FM board, this is about in the center of the FRG, about
110 mm from the back panel.

On this board there is an IC MC3357P. Locate the pin Number 14 and solder
one leg of the capacitor to the soldering point where this pin is 
connected.

Pin number 14 is the third pin of the top row of the IC, starting from
the side where the IC has the notch. 

Now solder the coaxial cable: the inner conductor has to be soldered to
the second leg of the capacitor, the outer conductor has to be soldered
to a place connected to ground, somewhere near the capacitor. Now use 
some insulating tape or cable tie to fix the capacitor and the cable in 
place, so they don't move around too much.

That's it. Now you can connect the other end of the cable to some unused
plug on the back panel of the FRG, and this will be your discriminator 
output.

WARNING: DO NOT ATTEMPT TO DO THIS IF YOU DO NOT
FEEL CONFIDENT WHEN USING SOLDERING EQUIPMENT.
DO NOT BLAME ME IF YOU SCREW UP YOUR RECEIVER OR
DO ANY DAMAGE TO ANYTHING YOU ARE USING.

Now check your solderings. They must be clean, and must not touch the
nearby pins. Close the box, connect the cables and turn it on.


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