Thank you for your answers. Yes, I was trying to run the Simulator before switching to the actual hardware. I had gotten the driver name incorrect, 'weewx.drivers.vantage' has resolved that issue. But now it is not getting ACK from the station. I have attached my conf file and the syslog:
Jun 20 15:58:03 redblack kernel: usb 3-3: new full-speed USB device number 29 using xhci_hcd
Jun 20 15:58:04 redblack kernel: cp210x 3-3:1.0: cp210x converter detected
Jun 20 15:58:04 redblack kernel: usb 3-3: cp210x converter now attached to ttyUSB0
Jun 20 15:58:04 redblack mtp-probe[13472]: checking bus 3, device 29: "/sys/devices/pci0000:00/0000:00:14.0/usb3/3-3"
Jun 20 15:58:04 redblack mtp-probe[13472]: bus: 3, device: 29 was not an MTP device
Jun 20 15:58:05 redblack systemd[1]: Starting Manage ttyUSB0 for GPS daemon...
Jun 20 15:58:05 redblack gpsdctl[13504]: gpsd_control(action=add, arg=/dev/ttyUSB0)
Jun 20 15:58:05 redblack gpsdctl[13504]: reached a running gpsd
Jun 20 15:58:05 redblack systemd[1]: Started Manage ttyUSB0 for GPS daemon.
Jun 20 15:58:19 redblack weewx[13531]: engine: Initializing weewx version 3.1.0
Jun 20 15:58:19 redblack weewx[13531]: engine: Using Python 2.7.9 (default, Dec 11 2014, 04:42:00)
Jun 20 15:58:19 redblack weewx[13531]: engine: Using configuration file /home/weewx/weewx.conf
Jun 20 15:58:19 redblack weewx[13531]: engine: Initializing engine
Jun 20 15:58:19 redblack weewx[13531]: engine: Loading station type Vantage (weewx.drivers.vantage)
Jun 20 15:58:19 redblack weewx[13531]: vantage: Opened up serial port /dev/ttyUSB0, baudrate 19200
Jun 20 15:58:20 redblack weewx[13531]: vantage: successfully woke up console
Jun 20 15:58:20 redblack weewx[13531]: vantage: No <ACK> received from console
Jun 20 15:58:20 redblack weewx[13531]: engine: Unable to load driver: No <ACK> received from Vantage console
Jun 20 15:58:20 redblack weewx[13531]: **** Waiting 60 seconds then retrying...
Jun 20 15:59:20 redblack weewx[13531]: engine: retrying...
Jun 20 15:59:20 redblack weewx[13531]: engine: Using configuration file /home/weewx/weewx.conf
Jun 20 15:59:20 redblack weewx[13531]: engine: Initializing engine
Jun 20 15:59:20 redblack weewx[13531]: engine: Loading station type Vantage (weewx.drivers.vantage)
Jun 20 15:59:20 redblack weewx[13531]: vantage: Opened up serial port /dev/ttyUSB0, baudrate 19200
Jun 20 15:59:20 redblack weewx[13531]: vantage: successfully woke up console
Jun 20 15:59:20 redblack weewx[13531]: vantage: No <ACK> received from console
Jun 20 15:59:20 redblack weewx[13531]: engine: Unable to load driver: No <ACK> received from Vantage console
Jun 20 15:59:20 redblack weewx[13531]: **** Waiting 60 seconds then retrying...