Coupling through coax shield does happen but it is really low but not zero. ?There is leakage through the bottom covers since it¡¯s only a press fit and not a perfect fit especially after it is drilled and riveted. It¡¯s not much leakage but at the lower end of the 2m band, the preferred can length should be the 26¡± long cans that are supplied for 138 to 144 MHz frequencies. The end of the resonator is closer to the covers than at 170mhz. Having the metal of the cabinet close to the bottom covers will help coupling between the cans. Not much but you are working down at the -120dBm range with transmitting power of 50dBm. That¡¯s 170 dB difference. ?A fix maybe to use conductive aluminum or tinned copper tape to seal that crack.?
