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When working on plain old telephone system (POTS) multiplexers, I came up with the following story which a service engineer insisted was true: An elderly lady
by ptaipale 9y ago
When working on plain old telephone system (POTS) multiplexers, I came up with the following story which a service engineer insisted was true:
An elderly lady with several pets called the operator to say that her telephone failed to ring when her friends called; and that when it did ring, her dog usually barked first. The engineer went to investigate.
He climbed a telephone pole next to the house, connected his test set, and rang the line to subscriber's house. The phone didn't ring, but the dog barked loudly. He tried again, now the phone rang.
Climbing down from the pole, the engineer found:
- This was in a country where the ringing was done from one of the wires against ground (not across the pair) (I think it was England).
- A dog was tied to the telephone system's ground post via an iron chain and collar.
- The ground post was in dry, poorly conducting ground.
- The dog was receiving >50 V of ringing voltage when the phone rang.
- With this torturous treatment, the dog would start barking and urinating on the ground.
- The wet ground now completed the circuit and the phone would ring.
OK, this story has a definite "urban legend" ring to it. Mythbusters wouldn't have tested it with a real dog, I guess.
- mseebach 9y ago> OK, this story has a definite "urban legend" ring to it. Mythbusters wouldn't have tested it with a real dog, I guess. It would be easy enough to test without involving a dog. They've done plenty of electric-shock myths with ballistic gel dummies.
- ptaipale 9y agoFair enough, but they'd have to build a voltage-triggered barking device in the gelatin dummy to make it sufficiently life-like.
- bartread 9y agoThis story has been doing the rounds since at least the 1980s. I remember hearing it from a BT engineer who was visiting our school back in the day. No idea if it's true or not, but it had certainly reached UK shores as of ~30 years ago.
- ptaipale 9y agoVery likely so, it's one of those legends that circulate round and round. I heard it when making a PSTN mux for (among others) UK market in about 1995.
- lb1lf 9y agoI (accidentally!) had the misfortune of torturing the cat in the apartment directly above mine, many moons ago. I had built myself a simple modem for packet radio (ham radio; very slow modem for use on shortwave bands), and wanted to test it. However, I was at home, and at the time I used either the HF station I had installed at my office in the university or the one at the radio club down the hill. Heck, I'd only try some local comms, anyway. I got an old transmitter out of a cabinet and strung up a dipole antenna under the ceiling in the living room. I tied one end to the curtain rack either end of the room, called the radio club, agreed on a frequency, and off I went. When I keyed the transmitter, I could hear a commotion starting upstairs. It died down, and I didn't think more of it. After a while, new commotion. Next day, I met the occupant of the apartment above at the mailboxes; she said her cat had acted up last night - running around the living room like it had the devil on its back. Turned out it had a metal collar, and loved to snooze on the floor right under the window, as the radiator on the wall below the window made it real warm and cozy there. When I keyed the transmitter, I basically had a very high RF voltage at the end of the antenna - and the cat, whose collar was a mere few centimeters away, got enough of a current induced in it for the cat to go ballistic. Poor thing.