When making or repairing electronic devices we can be much more efficient with proper measuring and testing equipment. We are often unable to solve unexpected problems without it. The problem is that devices like oscilloscope or signal generator can often be too expensive for students or amateurs. Signal generators usually have very low output current and high internal resistance of 50 Ω. That can be quite a problem with dual channel oscilloscopes since one channel is used to measure the output of our signal generator, making us unable to concurrently measure more than one node.
The goal was to make a low-cost signal generator with small output impedance and large output power. Sample frequency was 6 MSps, limiting the output frequency to 1 MHz. Output voltage swing is ±13 V. Output current is limited to 333 mA. The generator can add up to 6 functions, including noise and DC offset. It is controlled by 3.5-inch touch screen, where we can choose desired functions and set their parameters. The screen contains a graph for easier representation of the output signal. The circuit contains a relay, used for high impedance output. For better compatibility with lab equipment, 50 Ω output with BNC connector is used.
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