Old L.H Lock... WHAT IS IT?

[MilesRottingham]

Hello all

I am new to lockpicking and am interested in vintage/antique locks

I just bought this little number for $10 off of someone and before I receive it in the mail I want to share a photo of it and see if anyone has any information on it

Any info that anyone can give on this lock would be super, as I have found diddly squat

Thanks
Miles

[femurat]

Hello and welcome to the forum. Remember the old rotary phones? That lock was used to lock the dial and prevent someone to dial a number. You could answer the phone but not make a call.

Cheers

[GWiens2001]

You could answer the phone but not make a call.

Unless you were good at using your finger on the button that 'hangs up' the phone. Then you could still make calls. My sister and I were pretty expert at it. It was a game for us.

Gordon

[MilesRottingham]

Wow, you're kidding, that's awesome, thanks for the reply

[bjornnrojb]

Hey Gordon, did you do that by tapping on the hangup button to replicate the sound of the number dial turning?

[GWiens2001]

Hey Gordon, did you do that by tapping on the hangup button to replicate the sound of the number dial turning?

Back then, the phones did not use different tones to dial. They had clicks. One click for the number 1, two clicks for the number two... all the way for ten clicks for the number 0. But the happened quickly. So we had to dial a phone number by hanging up and releasing the button very rapidly the number of times required for the number first digit of the phone number to be dialed. Then wait about a half second, and dial the next digit in the phone number. Keep at it until you have dialed the number.

Gordon.

[RumballSolutions]

Hey Gordon, did you do that by tapping on the hangup button to replicate the sound of the number dial turning?

Back then, the phones did not use different tones to dial. They had clicks. One click for the number 1, two clicks for the number two... all the way for ten clicks for the number 0. But the happened quickly. So we had to dial a phone number by hanging up and releasing the button very rapidly the number of times required for the number first digit of the phone number to be dialed. Then wait about a half second, and dial the next digit in the phone number. Keep at it until you have dialed the number.

Gordon.

You wouldn't be talking about that old phreakin technique of switch hooking there would you Capn Crunch? Surely not discussing toll fraud are we.......

[GWiens2001]

Hey Gordon, did you do that by tapping on the hangup button to replicate the sound of the number dial turning?

Back then, the phones did not use different tones to dial. They had clicks. One click for the number 1, two clicks for the number two... all the way for ten clicks for the number 0. But the happened quickly. So we had to dial a phone number by hanging up and releasing the button very rapidly the number of times required for the number first digit of the phone number to be dialed. Then wait about a half second, and dial the next digit in the phone number. Keep at it until you have dialed the number.

Gordon.

You wouldn't be talking about that old phreakin technique of switch hooking there would you Capn Crunch? Surely not discussing toll fraud are we.......

I didn't say nothing! Innocent of all charges. The claims are false! You are just trying to shift blame from you to me!

While we mostly did use this at home for the challenge (and when the phone dial was broken), it did work on pay phones before they used tones. But you had to memorize and copy the click pattern for the coins.

Gorodn

[peterwn]

Hey Gordon, did you do that by tapping on the hangup button to replicate the sound of the number dial turning?

Back then, the phones did not use different tones to dial. They had clicks. One click for the number 1, two clicks for the number two... all the way for ten clicks for the number 0. But the happened quickly. So we had to dial a phone number by hanging up and releasing the button very rapidly the number of times required for the number first digit of the phone number to be dialed. Then wait about a half second, and dial the next digit in the phone number. Keep at it until you have dialed the number.

Gordon.

To put it more accurately, there is 50 volts DC across the 'pair' (the pair of wires back to the exchange), but a capacitor blocks DC current (but passes ringing current which is 17Hz or so). When phone is off-hook a DC current flows operating a relay in the central office which seizes switching equipment and returns dial tone. The rotary dial interrupts this DC current as it 'returns' producing 1 to 10 'breaks' at the rate of approximately 10 per second. These impulses operate the selectors directly in the old Strowger central offices (used in smaller cities) or were counted by the common control equipment in the panel or crossbar central offices (in New York etc). Long distance 'phreaking' consisted of emulating the voice frequency tones that controlled the long distance switches. Switch hook 'tapping' was also relevant for the old British pay phones (with the A and B buttons) as the dial was shorted out until the relevant coins were inserted, although 9 and 0 could always be dialled to reach the operator or make a 999 emergency call. The cash boxes on these old British payphones were secured by 6 individually keyed lever barrel key (or similar) locks and were virtually impregnable.

Discussing this here does not compromise 'security' as all this is now obsolete technology.

[Jacob Morgan]

Strowger was a Kansas CIty undertaker in the late 1800's who thought that the local switchboard operator was diverting business to his rival...so he invented the eletro-mechanical phone switch and did away with the switchboard operator. It is explained in an episode of The Secret Life of Machines https://youtu.be/MCgCSMq5Xpo (go to the 14 minute mark to start). The video even shows an early burglar alarm auto-dialer.

A good example of someone whose system was being compromised and then invented a countermeasure.