The 788's throws out different amounts of RF, it all depends on the unit. some are better than othes, but it all comes from the AD's (analogue to digital convertoers), there are several trick to help reduce it but no cure.
my guess would be if the Nomad is throwing out any RF it will effect the range of your radios, the only thing i could suggst would be to move your antenna to you shoulders, try and put as much space between mixer and RX. just remember though you loose about 1/4 to 1/2 a DB of gain for every connection you introduce in to the antenna's so that will also effect your range
RF's a bitch