Instead of the traditional ring-ring, the phone would ring its bells off like a fire alarm.

This is how the NSWFB page their on-call firies. I was at a mate's place back in the late 1990s installing security lighting for him and his phone rang continually for 60 seconds and I said what does that mean. As he jumped into his overalls and helmet he yelled "I'm on a call, see you in an hour".

Not sure if I had related this story before but here goes:

Back in the late 70s my business did conversions of colour TVs so they could work as video monitors.

We did field work as well and we had a VHF low-band 2 way radio system to keep in contact with the field vehicles all over Sydney and surrounds.

Business grew, we moved to an office-warehouse unit in Brookvale. No point in installing the radio here, we put an order in for a Telecom leased line as was the practice of the day, so the radio base station transceiver could be sited more advantageously (Frenchs Forest) and still used from the office (Brookvale).

After a few weeks, a Telecom tech drops by. Tells us he's come to check for an available pair to the street (no problem there).

"How long is it going to take to get our landline connected?"
"Oh, usually a couple of months"

We expressed our disappointment. Then he looks around the place.

"Do you guys fix TVs?"
"Well, yes"
"Mate of mine has a Sony 12" that doesn't work. He wants $30 for it. What do you think it would cost to fix?"

Silly question of course but then I had a lightbulb moment.

"You get our landline on today and I'll fix it for free!"
"Er .... Can I use your phone?"

Guy was as good as his word, calling in favours from mates at the 3 intervening telephone exchanges to have the necessary tie-lines patched. We got our radio landline and he got his cheap TV working.

But that wasn't the end of the story.

A couple of years later I was driving to work when a phone conversation suddenly appeared on the radio in the car.

As it turned out, part of our line had been used to connect a PABX extension in a carpet warehouse - as we were able to deduce from the frequent phone conversations we were intercepting!

Eventually, someone dropped a phone number! Gotcha! Rang the number:

"Who were you just talking to?"
"Why?"
"Well you see there is this crossed line and your phone conversation and lots of others are being transmitted by radio all over Sydney!"
Slight pause as it sunk in...
"Oh!"

With this guy's willing cooperation we were able to track down the source of the trouble and pass it on to Telecom. It was fixed the next day!

Turns out that although we had a legitimate N number assigned to our line, it was completely undocumented (Surprise surprise) and Telecom had to completely redo the line (and give us a new N number).

That wasn't the end of the story either but maybe that's a tale for another time.....

In the mid eighties my place of work had IDF and MDF phone patch bays distributed throughout the building.
On one of the maintenance benches there was an MDF frame.
One of the guys worked out that one of the pairs went to phone in an unused office.
He rigged up a relay which would close a pair of contacts if that number was called.
He then ran a sneaky pair of wires to the neutral and earth on one of the GPO's on the bench.
When the number was rung the ELCB for the bench would trip.
When he was home and the opposite shift was on he'd ring the number and the breaker would trip.
It sparked a lengthy investigation as to why the breaker would seemingly intermittently trip and what piece of gear was causing it until someone twigged that it never occurred when that certain person was on shift.
The lengthy entries in the fault log were a treat to read.
It was named Dial a Breaker.

Irext's story reminded me about an episode at a place where I worked in the late 1970s. Equipment spares and various tools were disappearing from the basement test lab at a fairly regular rate. It got to the point where everyone who worked in the lab was under suspicion of stealing stuff. Without telling anyone else, one of the engineers set a trap for the thief.

Figuring the thefts were probably occurring after hours, he hooked up a portable video recorder and camera inside the lab so that when the lab lights came on it started to record. (The lab had plenty of video gear available as that was part of its function.) To camouflage the camera, which back then was comparatively large, he lay it sideways on top of a Brownbuilt cupboard and put a corrugated cardboard cover over it from an incandescent light bulb, so that from the front it looked just light a light bulb among the other stuff on top of that cupboard. The camera was aimed directly at the entrance door.

Some days afterwards this paid off. The night before, as shown on the tape, after switching on the lights, in through the door came the night shift computer operator from a few floors above. He rummaged around and found a PC type computer fan which he put in the pocket of his white work coat, switched off the lights and left. Confronted with the video evidence he quickly confessed to being the long term thief and was handed over to the police.

As to how he got in, the lab door had one of those Schlage locks that can be fairly easily opened with a credit card or screwdriver. Needless to say a much better lock was installed afterwards.

I remember those Shlage locks.
They were all the rage in the 60's.
They had the knob in the centre of the door with an ornate surround.
Our family home had one when I was a kid.