In this episode Shahriar investigates the failure of an Anritsu MS2712B 1.7GHz portable spectrum analyzer with built-in tracking generator. The instrument is missing the main firmware flash card which is easily replaced. A full teardown of the instrument is presented with focus on both the tracking generator PCB and main RF deck. Various ASICs and microwave components are closely examined. To help with removing and replacing many microwave screws, a Hitachi/Metabo electric screwdriver is used which can be purchased here.
After re-assembly of the unit, it becomes apparent that a mechanical push on the RF deck causes the LO1 PLL to unlock. This points to a fault in one of the microwave components. The issue is traced to a broken solder joint inside of the VCO modules. After repair, the instrument functions normally. The performance and tracking generator functionality is verified by measuring a tuneable band-pass filter.