The SQG60-DC is a 10:1 passive low impedance probe with DC coupling that measures from 0 Hz to above 6 GHz, the widest range in the SQG series. The SMA output connects to oscilloscopes and other instruments with a 50 Ω input, and the probe picks up the fastest digital and RF signals directly on the PCB without soldered wires.
With no DC block in the signal path, the DC level, the edges and the RF content are shown in the same capture. The response is flat within ±0.5 dB from DC to 5.2 GHz, so a slow drift and a fast transition on the same line are measured on one amplitude scale.
Typical measurements include logic levels, overshoot and settling on clocks and fast data lines driven from low impedance outputs, with usable data rates up to 12 Gbps at the fundamental for level and timing checks. Signals at terminated 50 Ω outputs and test points, and supply rails where ripple and transients are seen together with the DC level, are measured the same way. On the RF side it covers front-ends below 6 GHz, including the 5 GHz Wi-Fi band, with the bias point visible in the same trace. Besides oscilloscopes, the probe works with sampling oscilloscopes, network analyzers, spectrum and modulation analyzers, receivers, power meters and millivoltmeters with a 50 Ω input.
The 333 Ω tip impedance applies at DC as well, so the probe draws a small current from the node it touches. It is best suited to low impedance points such as 50 Ω lines, terminated outputs and supply rails, while a biased high impedance node is better measured with the SQG60-AC. The typical tip capacitance is 0.35 pF, the return loss for the probed line is typically -23 dB to -6 dB up to 6 GHz, the transition time is below 52 ps and ringing stays within 0.26 dB at 6 GHz.
The probe is grounded with dual spring-loaded ground needles that fit its 5 mm (0.20 in) probe head. The two needles sit 3 mm (0.12 in) on each side of the signal needle, 6 mm (0.24 in) apart, and keep the ground return short and symmetrical up to 6 GHz. A spare spring-loaded test needle is included for when the first one wears.
Every SQG60-DC is marked with its own serial number (SPID), and the S-parameters measured on that specific probe can be downloaded for simulation or de-embedding. The probe weighs 34 g (1.2 oz) including the 1.2 m (47 in) cable, and the low center of gravity keeps it still in a PCBite holder during long captures. It can also be used handheld, and it comes in a storage case with the probe holder, an SMA wrench, color coded cable holders and a 5 mm tip protection cap.
The probe is rated CAT 0 under IEC 61010-031:2022 for circuits not directly connected to mains, with a maximum continuous input of 13.0 V RMS at the probe tip.
