[Texasrocker]

I agree with Ron!! Most likely, if the candohm hasnt been replaced, it is "trouble" waiting to happen!! Those rascals are T-r-o-u-b-l-e!!! Worst invention ever conceived IMOP!! Other sources of "intermittent 120 cycle hum", can be from modern in-home appliances such as clothes dryers, washing machines (spin cycle), other inhome modern appliances such as TVs sets, microwave ovens , etc. All play "havoc" on vintage tube radio reception!! The new style small "florescent tubular coil type light bulbs" that save-energy in our homes produce a "not so friendly" audio into vintage tube radios!! A good way to "isolate" AC interference ( if that is the prob?), .. is by connecting the vintage tube receiver to a AC (power strip) via end AC plug connected to 2 (.1-600v) bypass caps with both ends (-)of the caps going to "earth ground"!! Sure eliminates " AC pole transformers line hash", but still wont compensate for a bad "candohm"!! Randal