/diy/ - Do It Yourself

>>1324225
You don't feed your signals into the oscillator pins. The NE602/SA602 is capable of generating the local oscillator (your carrier) by itself using that internal transistor there. Adding external capacitors and inductors in colpitts or hartley configurations or crystals in fundamental or overtone mode will allow you to use the chip to generate the carrier for you. The internal oscillator works up to 200MHz. You can also feed in an external carrier to pin 6 directly and leave pin 7 unconnected.

Audio goes in pin 1 or 2. Output is pin 4 or 5. The reason there are two outputs is because the IC is a double balanced mixer. If you are feeding in balanced audio you will use both connections. Since you probably aren't you can use it single ended by using one of the two inputs and outputs, doesn't matter which you pick. Leave the other one unconnected or bypass it to ground with a capacitor. DO NOT simply short it to ground. These pins are internally DC biased and shorting them to ground will make things get hot fast. It's worth noting because of the DC bias on the inputs and outputs all your signals into and out of the IC should be AC coupled as well.