Looking at the Flex 6400, What exactly is the GPSDO for?

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  • Updated 2 years ago
I just reserved a Flex 6400, but after looking back at it.  I one-click reserved it of sort.  When I click on the radio to buy, it has offers of ATU, extended transmit coverage, GPSDO, and FlexControl.

The extended transmit coverage I'm guessing is MARS, etc.  I do want the ATU, so I supposed I need to cancel and re-reserve with it.  As for the GPSDO; I know what GPS is, but what does it add to the Flex 6400?  Is it for APRS or something similar?  I'm trying to figure out if I want/need this feature.  I just need to understand what the feature brings to the radio.

David ~ K1SZO
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Posted 2 years ago

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Mack McCormick, Elmer

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The GPSDO brings extremely accurate frequency standards to the radio. This is very useful at you UHF and super high frequency ranges. It is also useful if you want to participate in frequency measuring test from the ARRL.


Alpha Team
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Jd Dupuy

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All of my Transverters 2/222/432/902/1296/2304 and 10Ghz have an input to use a GPS Time and Reference receiver. For over 15 years I have used HP units into a 10 MHz splitter amplifier to lock these units down so they don't drift. Connected to a GPS antenna on the roof it does its job.The GPSDO does the same thing from within the radio. Yes not cheap, but if you want the capability you get it.
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Pat Cahill

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Another use for the GPSDO is to provide its accurate 10 MHz signal to test equipment that has an external time base.  I have a distribution amplifier with 8 outputs that feed the time base to my frequency counter, RF signal generator, oscilloscope and spectrum analyzer. As I type this, my frequency error is 1.01e-11, which is much more accurate than anything else I have.  I also have plans to use this for a 432 MHZ transverter someday soon.    My GPS antenna is attached to a south facing ground floor window  (behind a stained glass hanging panel for camouflage) through  a 20 foot LM240 jumper to reach the radio.  The GPSDO is seeing 13 sats, and is tracking 10 of them right now.  
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This can be added later correct?  With everything noted, it does seem like I can use it.  Though I won't have an immediate use for it.
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Tim - W4TME, Customer Experience Manager

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That is correct.