Have a system comprising 4m simplex link and 2m repeater running from same PSU. Tried using a brushless fan to boost cooling but when running and connected on the same PSU as the RF kit, the noise generated on 4m TX audio (not 2m), a very loud buzz, is incredible. Obviously the inverter noise is being carried back into the PSU so some sort of filtering is needed as, when the fan is run on a separate supply, there is no problem.
Has anyone encountered such a situation and if so what circuit or device was used to cure the noise (other that a second PSU)? Regards, Doug - GM7SVK
