Telephone busy call back one-key-through controller

The utility model discloses a busy connecting call back phone PTT controller, which relates to a telephone annex, in particular to a busy connecting call back controller in a telephone. One switch terminal of a electronic pulse switch (K1) is connected with one wiring terminal of a household telephone-line (5) by (5-1); the other switch terminal of the electronic pulse switch (K1) is connected with one wiring terminal of the telephone (6) by a cable wiring (6-1); two power input terminals of the rectifier circuit (1) are connected with the two wring terminals of the telephone; the output terminal of the rectifier circuit is connected with the signal input terminal of a control switch circuit (2); the control signal input terminal of the control switch circuit is connected with the control signal output terminal of a code and control circuit (4); the high electronic potential pulse signal output terminal of the code and control circuit is connected with the high electronic potential pulse signal input terminal of a electronic pulse switch (K1); the signal input terminal of the code and control circuit are connected with the two ends of a constant-opening button (T1).