In this episode Shahriar takes investigates the architecture and benefits of a precision sub-sampling wide-bandwidth oscilloscope. The teardown of the Agilent DCA instrument reveals a PC core combined with the acquisition board. The instrument without any plug-in modules does not perform any exciting tasks.
A 20GHz sampling module from eBay is available. However, the unit does not have an front connectors. New connectors are sourced from an old timing module and the sampling head is back to working condition. In order to test the unit, an Optellent OBP-04×10 4-channel pattern generator and error counter is used. The teardown of the unit reveals a simple design built around several transceiver ICs. The comparison between the sub-sampling scope and a real-time scope is also presented alongside measured results from the DCA.