I'm wanting to buy a external gpsdo for my flex 6400. If you have purchased one will you please send me the link and reviews.

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  • Updated 8 months ago
I'm wanting to buy a external gpsdo for my flex 6400. If you have purchased one will you please send me the link and reviews.
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James Skala

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Posted 8 months ago

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Randy Harris

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 I am using a Trimble Thunderbolt GPSDO with my 6500. These are widely available as surplus from Cellular providers and on E-bay. It works great and is rock solid. I have one of the 10 MhZ out ports connected to a calibrated Fluke Counter and it measures a solid 10.0000000 with an occasional drift to 10.0000001 Mhz for about 0.5 seconds. I run my GPSDO continuously rarely ever turning it off. 

Randy Harris W4HCR
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Larry - W8LLL

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A lot of flex users are using this one including me, this thing never drops its connections to satellites and the gps antenna doesn't even have a view of the sky.

 https://www.ebay.com/itm/GPS-Receiver-GPSDO-10MHz-1PPS-GPS-Disciplined-Clock-w-Antenna-Power-Supply-...
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Ted VE3TRQ

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I also have this one, plus a 10 MHz distribution amplifier, bought from the same seller. Comes with a 25 ft antenna cable, enough for me to get it out of the basement. Has a 10 MHz output used to drive the distribution amp, plus 1 PPS and RS232 output which will eventually control the ntp daemon in a Linux PC.

I should add that it is powered by my shack supply.
(Edited)
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Mark WS7M

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Using the same.  Rock solid.  Just wish the coax to the antenna was a little longer but it does work just fine.
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Cal Spreitzer

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Also using the same GPSDO as Larry.  It's worked flawlessly for over a year and a half now! 

Cal/N3CAL
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Gary w8vi

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How does it connect to the Flex 6600?

Thanks and 73,
Gary
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Dave Gipson

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I did this for another project but am now using it with my 6600M. I thought I "might" need to tap into it for a "few" other uses hence the distribution amplifier. It worked great spread across the workbench. Now it is packaged and in the rack. It's been powered up and working over 6 months now.













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Ted VE3TRQ

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Gary w8vi,

The 6600 has a 10 MHz input on the back for a GPSDO.
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Gary w8vi

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Thanks Ted,

I am operating remote right now but from the picture diagram on the Flex site I see the gold GPS ANT and 10 MHz OUT connectors. 

I guess I would use the 10 MHZ Out - correct?

73, 
Gary
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Larry - W8LLL

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Its the 10 Mhz in
RCA jack in the picture.

(Edited)
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Gary w8vi

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Thanks Larry for the picture and the correct location.  I was unable to see it clearly from my smart phone screen.

I will also be ordering a GPSDO.

73 and all have a prosperous 2019.
Gary
W8VI
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Scott Russell - N1SER

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For anyone reading this post and is not familiar with the back of the 6400/6600, the two SMA GPS Antenna and 10MHz Out jacks are not included with the radio if you do not get the Flex GPSDO installed. They are just blank plugs and do not come with the radio. I found this odd when researching the radio before actually getting one that the photo associated with the "Non" GPSDO option standard 64/6600 is misleading. Just FYI.
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WA2SQQ

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I know 2 persons using this. Works verybwelll.
https://www.ebay.com/itm/GPSDO-GPS-cl...
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Bob Gerzoff, WK2Y

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If someone could point me to a good article that would explain why I would want an external GPS, I would be very grateful. Thanks and Happy New Year. 73 Bob WK2Y
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Ted VE3TRQ

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Can't really point you to an article, but if you use transverters, the higher the ultimate frequency, the more important the LO accuracy. And if you are doing satellite, you can ensure you are on frequency if providing an accurate common clock. I'm sure those who use transverters regularly can add a lot more.
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Bob Gerzoff, WK2Y

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Thanks. Not into that yet but who knows. 73 Bob