You can only mesh same radio types. 2942 is 11g so it can mesh only to another 11g, like 2741, but not 11gn. 7343 will mesh with 7341 or 7352, but not 7363 or 7372 for example as they are dual-band.
If I'm not mistaken 7321 will mesh with all except 11g. You just have to set the right frequency.