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What is an appropriate TXDelay to use for a THP 1.5KFX amp

Doug Seyler
Doug Seyler Member ✭✭
edited October 2015 in FLEX-6000 Signature Series
I have a THP 1.5KFX amp that I have been using with the 6300 on SSB and it works fine without any TXDelay. However, when I try CW it trips the Pr (reflected power) safety, even with fairly low drive power and a resonant antenna. I suspect that I need to put in a small TXDelay. Any suggestions short of incrementally increasing it until it doesn't trip?

Answers

  • Ken N9VV
    Ken N9VV Member ✭✭
    edited January 2015
    Hi Doug,
    the ARRL "TOR" test was for ancient PACTOR and AMTOR digital programs that required a T/R time of 20ms of less. In the "old days" there were many rigs that met this requirement. However recent rigs vary quite a bit in their T/R times.  If I remember correctly, a dit at 40WPM = 20ms.  
    To avoid "hot switching" I would recommend 40ms or greater and see how it works out for your favorite speed and switching circuits.
    GL de Ken N9VV

  • Ken N9VV
    Ken N9VV Member ✭✭
    edited January 2015
    Doug, you might find this chart interesting. Go to the right hand columns and you will see the ARRL T/R test results for various modern Transceivers;
    <URL: http://www.remeeus.eu/hamradio/pa1hr/productreview.htm >
    GL de Ken N9VV
  • Charlie
    Charlie Member ✭✭
    edited September 2014
    I had the same problem with my 6300 and THP.  I am using 5 ms TX delay and it works fine.  No more Pr errors.
  • Doug Seyler
    Doug Seyler Member ✭✭
    edited August 2015
    Thanks, guys, for all of the help!

    Doug WB5TKI

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