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Aplitude and clock sync issue

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Post time 2019-1-18 08:44:10 | Show all posts |Read mode
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,

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Post time 2019-1-18 10:52:13 | Show all posts



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

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 Author| Post time 2019-1-21 03:22:41 | Show all posts
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?

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Post time 2019-1-21 14:42:07 | Show all posts
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.

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 Author| Post time 2019-1-21 22:36:24 | Show all posts
Thank you very much.  This would be very useful information to add to the manual.

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 Author| Post time 2019-1-28 02:30:25 | Show all posts
I completely forgot to ask.  What should be the impedance level of the external 10 Mhz clock in?  50Ohm?
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