Trimble Thunderbolt GPSDO

[TheSteve]

A friend of mine dropped off a Trimble Thunderbolt GPSDO that stopped working. The OCXO still heats heats up, all voltages/supplies look good. I can see activity on the data and address lines of the firmware memory(29F400) however the data sure looks ugly. You can see edges galore on every single data line, they aren't from a probe grounding issue.

I have attached a pic, the yellow trace is an address line, the blue is a data line. I really can't imagine something working with such noise on the data lines.

Thoughts?

[edpalmer42]

What do you mean by "stopped working"?  Stopped talking, off frequency on one or both outputs, all of the above?

Ed

[TheSteve]

What do you mean by "stopped working"?  Stopped talking, off frequency on one or both outputs, all of the above?

Ed

All of the above. There is no serial communication and the OCXO is not controlled.