AOR AR-3000A (AOR3000)
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To add a discriminator output to an AOR AR-3000 (AOR3000), the scanner has to be disassembled a bit, as the discriminator IC is on the bottom side of the IF PCB.
You find this print if you open the bottom half of the housing by removing the 4 screws at the bottom and on the rear. To facilitate handling of the scanner, I also disconnected
the loudspeaker PCB connector.
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The AOR AR3000 |
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The IF PCB is kept by 6 screws. After removing these screws, the PCB can't be taken from the scanner yet.
I disconnected and labeled the thin gray cables to J1, J4, J5, J10 and J11.
Then you can carefully turn the print to the right and reach the discriminator IC
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The opened scanner with IF board |
The other side of the IF board |
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The discriminator output is made to pin 9 of the discriminator IC, an SMD MC3357. One leg of a limiting resistor of 10 k (this value is not critical, I use values between niet 5,6 and 15 k)
is bent so that it follows the IC's pin. Next, this resistor is connected to pin 9 with a only small amount of solder. The resistor is glued to the IC with a drop of glue from a glue gun.
The other leg of the resistor is connected to a small piece of insulated wire, which is connected to the AUX connector on the back later on.
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The location of the MC3357 |
Pin 9 with limiting resistor |
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After this, the IF board can be put back. Thanks to the labels, all disconnected cables can be connected with the right connector.
Pin 1 of the AUX connector is still free. The wire coming from the limiting resistor is soldered to this pin. To make the AUX connector easier to reach, the 25 pin Remote connector can be removed temporarily.
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The AUX connector |
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