The MMCX adapter fits the 5 mm (0.20 in) probe head of the PCBite SQG60 and connects the probe signal and ground directly to an MMCX connector on the PCB. The ground path becomes as short as possible, which keeps noise pickup to a minimum.
This matters most on sensitive circuits such as power supply designs and analog stages. With almost no noise picked up through the ground path, ripple on supply rails can be measured accurately instead of disappearing in probe noise.
On the SQG60-AC and SQG60-DC the adapter adds length to the signal path, which places the −3 dB bandwidth at about 3.6 GHz. Above that the probe continues to measure, with a gradually lower signal. For measurements at the full 6 GHz, use the dual spring-loaded ground needles.





