flex 6500 direct control of SPE 2k-FA

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  • Question
  • Updated 7 months ago
  • Answered

The Flex 6500 connects to my PC by an Ethernet cable.  The Flex rear panel USB connections are not

The 2k-FA has 2 cables: 

  1. USB cable from 2k-FA rear panel to pc USB receptacle, and

  2. A proper DB15 to DB9 cable to a FTDI chip conversion of RS232 to USB and then to pc USB receptacle.

The SPE software “Term-2k-USB.exe” controls the 2k-FA as expected but frequency / band information is not passed from Flex to 2k-FA without performing a Flex Tune to utilize the 2k-FA internal frequency counter to jump to the proper band.

How do I get the 2k-FA to automatically follow the flex changes in bands, without having to initiate a Flex tune? 

Do I need to use the Flex rear panel USB receptacles, with a USB cable from Flex to the pc?  Or, the Flex USB to “USB – RS232 FTDI chip conversion to DB15 connector” cable directly to the CAT port of the 2k-FA?

Thanks for any advice.

Mike, K6DRY
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Michael Reid

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Posted 7 months ago

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Photo of Ria - N2RJ

Ria - N2RJ, Elmer

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You can either use DDUtil, and select a port to follow the radio which will allow operation of ONE input to the amp. 

You can use the USB cables on the back of the radio which will allow two inputs to be used (for SO2R). This also does not need a running Windows PC.

There is another very recent (today) thread about this. I don't feel like retyping everything so if you could go there you'll find everything you need. 
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Mark Erbaugh

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You want to connect  the FTDI cable to one of the USB ports on the 6500 rather than the PC. Then go into the Setting menu in Smart SDR and select USB cable. Configure the USB port as SPE Amp. I'm using the setup here and it works fine. The amp changes antenna and tuning for each band and segment within the band as I change frequency on the Flex (I have a 6700). The amp also automatically reduces the RF power setting when I switch the amp to operate as to not overdrive the amp. Consult the SPE documentation on how to set the RF level.

I have multiple antennas for some bands (as well as port 6 on the amp is connected to a dummy load). I use Term-2k-USB to switch antennas as well as going between standby and operate. 
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David Livingston

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Buy the cable from Expert Linear.  I had mine made by them and it works perfectly on my 6700. Runs from a USB port on the Flex. 
Photo of dj3cq


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as Ria said, often discussed and easy. I'm running your configuration for a long time without problems. Buy a FTDI cable, connected between the 6500 and the amp.
Configure the 6x00 as Mark said.
A diy cable is needed from FTDI DB9 to the amps DB15. This cable is vy simple, just rx, tx and ground.

Works fine, the amp is following the Flex like a well educated dog should do :-)

73, Jo