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What are the specifications for the TX Relay Outputs on the FLEX-6000?

Tim - W4TME
Tim - W4TME Administrator, FlexRadio Employee admin
edited December 2018 in FLEX-6000 Signature Series
Are there any electrical specifications for the TX Relay connections? Are they open collectors or drains? Or are they actual relay contacts? What is the maximum current and voltage?


  • Graham-KE9H
    Graham-KE9H FlexRadio Employee ✭✭
    edited August 2013
    The TX1, TX2, and TX3 are open drain outputs suitable for driving relays (or logic inputs) directly. The load or logic to be driven should appear as a pull-up to some positive voltage source. Open circuit voltage should not exceed +40 Volts DC. Closed circuit current is 150 mA continuous max, and 500 mA peak max. There is the equivalent of a +45 Volt Zener across the output to ground that will clamp any positive going transient peaks at about +45 to 50 Volts. --- Graham / KE9H
  • Gerald-K5SDR
    Gerald-K5SDR FlexRadio Employee ✭✭
    edited August 2013
    You can review the full specifications for the TPIC6B595 the relay driver we use at: http://www.ti.com/lit/ds/symlink/tpic6b595.pdf Gerald, K5SDR
  • K4EAR
    K4EAR Member
    edited March 2017
    Why do all the TX1,2,3 outputs fall out at the same time with release of PTT? They are timed going in, but collapse simultaneously with PTT release or TX delay, whichever is the >
  • Tim - W4TME
    Tim - W4TME Administrator, FlexRadio Employee admin
    edited December 2016
    This is a great feature enhancement suggesting that's separate from the main topic, so I created a new topic to in the Share an Idea category to continue the discussion. Please reference the new topic here: Add a feature that would make the TX Relay act like a sequencer
  • David Ahrendts
    David Ahrendts Member ✭✭
    edited December 2018
    Tim, I want to create a simple "On The Air" lighted sign for my Flex 6500. Is there any problem in running 12VDC through TX1-2-3 without a relay for a few LEDs? Thanks.

    David A., KK6DA, Los Angeles
  • Tim - W4TME
    Tim - W4TME Administrator, FlexRadio Employee admin
    edited May 2017
    The spec in the FLEX-6000 hardware manual state +40 VDC @ 140 mA maximum

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