Aplitude and clock sync issue

ewaldo

I recently purchased an HDG2002b and have two significant problems.  The first thing I did is upgrade to the latest firmware.
First, the amplitude and offset voltages are off by 2.  If I set the amplitude from +1V/-1V, it's actually .5V/-.5V, likewise 6V/-6V gives me 3V/-3V.  The offset is the same.  If I give a +1V offset it's offset by .5V, +2V offset measures +1V offset.  I would guess that this is a software bug in the firmware.

Second I am attempting to synchronize to a highly stable Trimble Thunderbolt 10Mhz GPSDO external clock source and there is a significant difference in frequency deviation and phase.  The sync is so bad that the internal clock source provides a much better match to my other synchronized equipment than when I attempt to use the external clock source.  Once thing I noticed is that the 10 Mhz external clock outputs a 10 Mhz square clock.  The Trimble Thunderbolt produces a 10 Mhz sine wave.  Should I able to use a 10 Mhz sine wave external clock or does it require a square wave clock?


Thank you for any information you can provide.  If it sounds like my hardware is acting abnormal,

amy

Sir, please give me the firmware version of your unit.
And about your problem, please take a video and send to me to study.

ewaldo

I found a calibration procedure and everything looks a lot better from a voltage perspective.  The external clock sync still isn't working.  I read somewhere that it might require a signal larger than +20dBm.  Can you confirm whether or not this will take a regular sine wave clock input and how large the signal needs to be?

amy

ewaldo replied at 2019-1-21 03:22
I found a calibration procedure and everything looks a lot better from a voltage perspective.  The e ...

You need to input a square with frequency 10MHz and voltage 0~3.3V to 10MHz In/Out connector.

ewaldo

Thank you very much.  This would be very useful information to add to the manual.

ewaldo

I completely forgot to ask.  What should be the impedance level of the external 10 Mhz clock in?  50Ohm?