COM port puzzle

  • 1
  • Question
  • Updated 4 years ago
SmartSDR says that I should use COM port 4 to connect 3rd party programs. Some won't connect to it (no other programs connected to it at that time). For example, I have had to connect WSJT-X to COM 6 [dedicated], that I 'made' for CAT.

Any idea why COM 4 cannot be used? Using TS 2000 in WSJT-X. This is not the only example I have come acroos. I have managed to get everything working, I'm just puzzled.

Mni tnx.
Photo of DrTeeth


  • 1687 Posts
  • 387 Reply Likes
  • Puzzled

Posted 4 years ago

  • 1
Photo of Al K0VM

Al K0VM, Elmer

  • 583 Posts
  • 95 Reply Likes
   My best guess is that a previous program that used COM4 did not close its com port connection when the program was closed..   It may take rebooting the PC to make sure that COM4 was indeed closed before WSJT can use it..   Or maybe the previous program was not closed before WSJT was opened, in which case, just close WSJT and reopen it.   
  That's where I would start.

Photo of George Molnar, KF2T

George Molnar, KF2T, Elmer

  • 1590 Posts
  • 555 Reply Likes
Also remember that each application needs its own COM port. A little confusing when the SmartCAT app says to connect to COM4 - but that's just the FIRST application you're using. Assign each program that needs either PTT or CAT functions its own port and you'll be in good shape.