My take on the "coil" aspect of this is that most I've seen are bumped out at the middle like a dromedary camel rather than double as a bactrian.
But--all kidding aside--my feeling is we need to see a schematic for this apparatus, or perhaps the instructions I outlined in a previous post describing specific picture-taking would perhaps give us all some hints as to what's going on.
As I might have said I am used to the martyrdom of having to cypher out a lot of these engineering cluges without such aid. Laced-together wiring of such as Tektronix practises usually makes a schematic essential. But a lot of this other stuff is freer in physical wiring nature, leaving open and more apparent the actual hookup of one part to another....
Pictures of the scene of the crime would help--perhaps....
