Re: [Vo]:Air threads

[Horace Heffner]

              ---------------
              |             |
Emitter       V             |
              .             |
                            |
              .             |
                            |
Ring    O     .     O       |
                    |       o-----C1----o AC Signal (Optional)
              .     |       |
                    |       |
Plates     ___ ___  |       T1=== AC
           |     |  |       |
           |     |  R4      |
           |  V3 o  |       P
           |     |  |       |
           |     R3 |       |
           |     |  |       |
           -o-R1-o--G---R2-o-
            |       |      |
            o       o      o
            V1      G      V2
    Fig. 2 - Circuit diagram for ring pass-through drop/thread  
detection


Fig. 2 gives a better diagram of the ring pass through concept.  It  
shows that there is at least one alternate current path through R4 to  
ground.  This takes fixed font Courier to view.

Regards,

Horace Heffner