[Radioroslyn]

Both, It may be a little less though the transformer. I have to same issue with my modern (1987 Kenwood transceiver) It uses a 35amp 12v transformer power supply. If I leave the set on and turn the p/s off as the filter bleed down there is very little noise. Goes from a S7 or so down about S1. With a S7 noise It's difficult to hear any weak signals. When I unplug my laptop switching charger noise drops to about S5.

Terry