SSDR CW Timing Error

  • 1
  • Problem
  • Updated 4 years ago
  • Acknowledged
  • (Edited)

Was working QRQ CW this evening on 40m and noticed a slight timing error with my Flex 6700 running SSDR V1.6.21.77.  An external keyer is used. 

Using a dual trace scope to check CW timing, I noticed that the start of the CW RF waveform jitters between 6 msec. and 11 msec.  Running a string of dits, the RF start point can actually be seen wandering at different points between those two extremes.  Prior SSDR versions did not show this behavior.  I confirmed that the key line pulse used to trigger the alternate scope trace is steady.

To be clear, this is not so-called "dit shortening," meaning the duration of the RF envelope isn't changing.  The start of the RF envelope is simply bouncing around between 6 msec. and 11 msec.  To the ear, it becomes much more noticeable as CW speed increases.  Knowing that the SSDR CW Speed control did have an effect on key shape, even with external keying, I changed settings but the result remained the same.

To validate that an error didn't creep into my test configuration, I confirmed that two other transceivers display steady CW start times using the same external keyer.

Hopefully Flex Engineering can have a look at this and localize the root cause in the latest SSDR version when run with the Flex 6700. 

Paul, W9AC

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Paul Christensen, W9AC, Elmer

  • 325 Posts
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Posted 4 years ago

  • 1
Photo of Tim - W4TME

Tim - W4TME, Customer Experience Manager

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Official Response
I have entered this detailed problem report into our bug tracker (defect #3422) for additional investigation. Thank you for the defect report.