The SD3239 is an inner DC block with SMA connectors designed to block unwanted DC signals while allowing AC drive signals to pass through across a frequency range of 7 kHz to 23 GHz. It features a blocking capacitor on the inner conductor with a typical capacitance of 474,000 pF, good insertion loss of 0.75 dB, and a maximum operating voltage of 100 Vdc. The device maintains 50 Ohm impedance with a VSWR of 1.35:1 and operates reliably over a temperature range of -65°C to +125°C. The SD3239 is commonly used in test and measurement applications, ground loop elimination, and signal-to-noise ratio improvement, providing isolation and filtering benefits in RF signal chains.