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sainsmart relay module

I watched with interest Mike Walker's youtube video presentation on the use of the Flex 6000 series and usb interface. I wonder if anyone has had an experience with the Sainsmart usb relay module with 16 relays? Thanks for any comment
Dave K9UK


  • Ted  VE3TRQ
    Ted VE3TRQ Member ✭✭✭
    edited December 2020

    I use an 8-relay module of that kind to control 120 volt devices with a RPi - works quite well. Not being used for my Flex. I drive the logic with 3v and the relays with 5v.

  • I have used the SainSmart USB-8 module direct from the Flex. I used it as a bit cable device for antenna switching before I purchased the 4O3A 2x8 antenna switch.

    This is the module I used.

    SainSmart USB Eight Channel Relay Board for Automation - 12 V: Usb Relay Module: Amazon.com: Industrial & Scientific


    Dave wo2x

  • Dave
    Dave Member ✭✭
    I have a Denkovi usb 8 relay board but have a use for at least 11 relays -- Just trying to put everything on one board --
    Dave - K9UK
  • Jim K4JAF
    Jim K4JAF Member ✭✭

    I have used the Denkovi relay board and the Sainsmart relay board, both work fine as my antenna switcher by frequency.

    Drives one of the 5 position remote antenna switch my MicroHam. Jim K4JAF

  • KR5OG Paul K
    KR5OG Paul K Member ✭✭
    edited December 2020

    This has been a great discussion, I have the Sainsmart board purchased from Amazon and will be doing the hookup in the next few weeks.

    from reading this discussion I am anxious to get started. I have found there are many more things it can be used for than expected.



  • One more comment, I had used the USB-8 board plugged into the Flex to drive a W2IHY 1x4 antenna switch. With a small experimenter's box, cable and connectors I had a 4 port automatic antenna switch that followed the Flex for under $200 total.


    Dave wo2x

  • Dave
    Dave Member ✭✭
    ok - Here is the plan -- I am ordering the Sainsmart usb 16 relay board on Amazon and will be testing when it arrives -- Let you know
    Thanks all for the comments,
    Dave k9uk
  • Lou KI5FTY
    Lou KI5FTY Member ✭✭

    So it seems dangerous to use this with a PI vs the Flex. I read that it resets the relays multiple times on reboot (usb version)

    "When the board is connected to the PC while PC is restarted, the relays will be toggled several times which because of the structure of the FTDI chip."

    How do you avoid transmitting into a grounded or open antenna port?

  • Dave
    Dave Member ✭✭

    My application is to have the relay board feed an antenna switching network (a diode matrix to sixpak) -- I will connect the board directly to the usb port on the Flex and let the Flex determine by band what relay is selected. I have not received the board yet but that's the idea if it works :).

  • Dave
    Dave Member ✭✭

    Sainsmart relay board (usb 16 relays). Tried and failed. The Flex did not recognize the board. Had no problems with the Denkovi 8 relay board and if my project continues I will just have two Denkovi boards instead of one board with 16 Relays. Lesson learned.

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