Automated Transverter Band Switching in VHFLOG and KM Rover
Win7 and Win8 Band Switching is supported using a CanaKit UK1104 USB I/O Controller. This unit also
has 4 relays so it might be overkill, but in VHFLOG the relays can be configured to follow band
The 4 BCD channel outputs are wired to a connector that plugs into your decoder box. Channel 5 is
used if required - read Note 1 below. A 0.10" (2.54mm) pitch header plug and ribbon cable at the
controller is easiest. Using the lock-out circuit below to prevent hot-switching is important.
Read #4 here.
The controller requires only USB power when generating band data. Jumper J1 is in position A.
Important note: A 12V/1A supply and J1 at position B is required for relay operation.
This is the manual and the UK1104 USB Windows driver is here. Read this if you get a message when
installing the driver: "The hash for the file is not present in the specified catalog file". After
driver installation, the COM port from the Device Manager is entered into the band switching setup.
The 4 BCD channels and data latch CH5 connections:
see note 1
You can send commands to the controller board using a Terminal Emulation program. Set the program
to the COM port listed in the Device Manager. Connect to the controller. Hit the <Enter> key to get
the :: prompt, which means the unit is ready. BCD Truth table.
::CHS.OFF <Enter> = BCD 0000.
::CH1.ON = BCD 1000.
Note 1: Optional lock out circuit control:
When the controller is set to a band, the BCD outputs are first cleared by setting BCD 0000. Although
unlikely, if this causes your switchbox to respond during the software write function (BCD 0000 = 6M),
connect CH5 to the `+V from Xvtrs on TX` input (with steering diode) to hold U1 enable low during the
COM port BCD write commands.
In any case, you need the lock-out circuits below to prevent hot-switching, as explained here in #4.
This BCD latch circuitry can be built on perfboard with a socket for U1 and installed in the decoder
box. Both U1 and Q1 are used, Q1 latch enable output goes to U1 Latch input.