An innovative scheme to convert signals from digital to analog is investigated in this paper. The Walsh transform allows performing a direct and an arbitrary waveform generation without any classical radio-frequency circuitry. The modulated signal is encoded by coefficients which represent its carrier frequency and its envelope. We present a Proof-of-Concept (PoC) using Components off-the-shelf (COTS) to demonstrate a low-frequency arbitrary waveform generator (AWG). The system is composed of digital signal processing using Matlab code, an FPGA, digital step attenuators, DAC, and an active combiner. We exhibit measurements results of modulated signals between 0 and 4.16MHz with an output power around 0dBm.