But unfortunately in this area of the world narrow band work in the 13cm band is done around 2320.2 MHz, and in this frequency most WiFi antennas simply suck.
I have a Interline INT-PAN-14/24-HV WiFi patch antenna. It works fine attached to a router, but how about 2320 MHz? I asked Alberto EA4GGE to test the antenna with his antenna analyzer and this is what he got:
As you can see, the antenna is tuned around 2440 MHz, covering the 2416-2476 MHz area with SWR under 1.5. But look at the left side of the graph. At 2320 MHz SWR is almost 3.5, making it a poor choice for a 13cm transverter.
Other WiFi antennas tested gave similar results. So to get the maximum performance from your transverter use antennas designed to work on 2320 MHz. You will notice the difference.