I find that sometimes it's good to draw a simple circuit diagram of problems like this to help work out what is going on. If anyone would like to send there fax number I could fax you what I would draw. If you do draw your own diagram I sure you will see a link created by the patient, however this link can not be used as an alternative return path. i.e. current leaving Generator A can not return to Generator A via Generator B.
An example of intermoduation or beat frequency been put to good use is the Physiotherapy Interferential equipment. TENS is a good alterative to drugs for pain relief, but as it is low frequency it only simulates at the surface. Interferentials use four pads with two high frequencies, where these frequencies mix a lower beat frequency of the difference is created. So it could be said the TENS effect can be felt deep in a knee or shoulder joint. The patient does not experience the tingling where the pads are applied because the low frequency beat frequency does not exist at these points. Neither leaving or returning to the generators.
Adrian.
