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#138584 09/17/03 07:31 PM
Joined: Dec 2002
Posts: 1,253
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djk Offline
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That kind of fraud was relatively rare here due to the lack of MF trunk signaling systems. The trunk system went from 1930s style to fiber optic in one jump. From the early 1980s all of the trunk & international switches went fully digital.

The few remaining local electromechanical switches were not very interesting to phreakers as there was no way of getting around their digital parents.

Making local calls for free was pretty much pointless as until 1993 Eircom charged a flat 11pence for a local call regardless of length. However, with the arrival of the internet and the dial-up modem they suddenly started charging. At the peak of dial-up internet modem traffic was representing up to 80% of all local call mins in some areas!

I was talking with a retired former Telecom worker who actually knew the full history of switching here:

1932-1962 Strowger equipment was being purchased and installed as new.
1954 - Ericsson crossbars began to appear in the system.
1962 - Policy was implemented to phase out Strowger gear and all new equipment was crossbar.
By 1972 at least 75-80% of automatic equipment was common control crossbar.
1978ish : RJ11 modular plugs began to replace hardwire & old style plugs (headphone jack like)
1978ish - Discussion about going fully digital
1979 - Trials of an Irish version of the French CIT/Alcatel E10B switch began. Within a short time the advantages were clear, low/no maintenence, easy to install & flexible (compared to crossbar), small size and very suitable for use in small rural locations as well as urban areas. By the early 1980s the Government had made it a matter of urgent policy to fully digitalise as a matter and pumped money in.
1980/81 - First E10 units went into public service.
slightly later Ericsson AXE switches began to appear.
Many of these went into local service in areas that were still manually switched i.e. rural areas at first.. any remaining step-by-step areas next and then crossbars began to be phased out starting with the oldest ones & any serving core-business areas i.e. city centres / industrial estates / business parks etc.
Crossbar systems installed in the mid-late 70s happily served residental areas as local switches providing very high quality service right up to the early 1990s.
1984: P&T split in 2 and replaced by an independent semistate company "Telecom Eireann" and a seperate post office "An Post"
1985 - Eircell, a TE subsiduary, launched a TACS mobile service using Motorola transmission and ericsson AXE switching.
Around the same time Minitel Ireland (joint venture between TE and France Telecom) appeared but, partly due to poor marketing and lack of any interesting services other than online banking, had very few users compared with French minitel.The service was pretty much dead and burried by the mid-90s although still exsists for some specialised closed-network uses.

1987-88 Smart card payphones appeared following trials of various magnetic and optical alternatives.

--------

Limited STD dialling exsisted back as far as it did in the UK but full STD didn't appear until the 1970s and then only in automatic areas so many rural areas were excluded until they went digital. 100% automatic service was later than the UK, but near full digitalisation was MUCH earlier.

IDD (International Direct Dialling) appeared in Crossbar areas in the mid 1970s to 20 countries via 16 + country code. Strowger switches were limited to STD and some calls to the UK.

Full IDD was available from day 1 in all digital areas
via 16 + country code

PhonePlus, later renamed Call Management services also launched around 1980 on the E10 switches & the AXE systems which followed later.

*Call diversion *21*+ no + # (conditional divertion [busy, no answer, offhook etc] came a few years later)
*Call waiting *43# (R2 to toggle between calls, R3 for three-way call, R1 to dump current call and go to next)
*Threeway calling
*Hotline, where you could programme a number with a code (not sure what it was now!) and once your reciever was off hook for 10 seconds it called automatically.
*Abreviated dialling where you programmed using *41*X*number# and could then dial by using a short code +#
*Alarm call *55*Time#
An automated charge card service also debued in the mid 80s.


*** more came later Voicemail & "Never busy fax", Caller ID, call return, etc.

Here's the inside of a very boring looking eircsson AXE 10 installed in the 1980s. The older gear looked more interesting.
[Linked Image from iol.ie]

[Linked Image from iol.ie]


[This message has been edited by djk (edited 09-17-2003).]

#138585 09/19/03 06:57 AM
Joined: Aug 2001
Posts: 7,520
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pauluk Offline OP
Member
I think that's one thing which made the old systems that much more interesting for visitors to telephone exchanges: With SxS they could see the switches physically moving as calls were connected and released, but in a modern digital office there's not much to look at except racks full of cards.

The modern CO is pretty quiet too. For anyone who has never been inside an old Strowger SxS exchange, this is what it sounded like.



[This message has been edited by pauluk (edited 09-19-2003).]

#138586 09/19/03 07:10 PM
Joined: Aug 2001
Posts: 7,520
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pauluk Offline OP
Member
Quote
Speaking of recorded messages, the US recently lost one of its most famous voices: http://www.nypost.com/news/nationalnews/1679.htm

It's funny how people can be famous even though most people don't know their names.

The majority of Brits will have never heard the name Carole Hersee, even though this little girl's face will be instantly recognized by almost the entire population of the country as "the girl on the test card."

Even though the name may be unfamiliar to most, I doubt there could be anyone in America who hasn't heard Jane Barbe at some time or other.

Click here to hear Jane in a typical role.

(Cue chorus from West of Pond: "Oh, now we know who you mean..." [Linked Image]).

#138587 09/19/03 08:39 PM
Joined: Dec 2002
Posts: 1,253
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djk Offline
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Telecom Eireann / Eircom use a guy called Connor Mullen, brother of U2's larry mullen to voice all of their announcements as part of their whole brand image. When they relaunched as eircom they came out with their own font and voice as part of the image.

This web page gives you an idea of what EVERY eircom service sounds like. There's also a branded female voice on directory enquiries and operator services.. very posh but friendly sounding.

The crossbar switches i've seen in operation were a LOT quietier than that. You just heard lots of gentle clicking as relays moved around. Sounded a lot like a lot of people typing on very "clicky" 1980s keyboards. That SxS sounds like something out of a victorian cotton mill!
http://www.tones.plus.com/sounds/menagerie/TTDUBLIN.WAV
is prob. a test number from one of the last remaining Ericsson ARF switch in dublin 10+ yrs ago.
[This message has been edited by djk (edited 09-19-2003).]

[This message has been edited by djk (edited 09-19-2003).]

#138588 09/19/03 09:42 PM
Joined: Apr 2002
Posts: 2,527
B
Moderator
I'll bet James Earl Jones ["Darth"] could make some very effective "Your telephone-bill payment will be expected in full by Tuesday. Do you have any questions about that?" calls.

#138589 09/20/03 09:47 PM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Paul,
Just regarding the DTMF system, how many actual tone frequencies are there to a standard telephone, as some of them sound similar when dialling a given number.
Also, what are these actual frequencies?.
I'm old enough to remember the old Manual exchange, when you would pick up the hand piece and you would hear(read this in a Marge Simpson voice!)"Number Please?". [Linked Image]
Not long after we changed over to the Auto exchange, I picked up the phone and had a Dial Tone, I instantly thought the darned thing was broken!!, no-one told me that the exchange had been changed over.

#138590 09/21/03 08:15 AM
Joined: Aug 2001
Posts: 7,520
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pauluk Offline OP
Member
Mike,

On a standard 10 or 12-button telephone there are actually only seven different frequencies used.

They are arranged on a row/column basis:

.....1209..1336..1477..1633 Hz

697....1.......2.......3.......A

770....4.......5.......6.......B

852....7.......8.......9.......C

941....*.......0.......#.......D


So when you press 5 for example, you send two tones of 770 and 1336 Hz.

It won't work on new phones, but for anyone with an original Western Electric 1500 or 2500-set, you can hear each tone individually by holding down two buttons in the same row or column, e.g. if you hold down 7 and 9 you'll hear a single 852Hz tone.

The 1633Hz column was in the original DTMF specification, and can be used for special signaling functions, although only special phones are fitted with these extra buttons (they were used extensively in the old AUTOVON military system in America).

By the way, if you listened to the Jane Barbe clip above, the burst of tone signaling at the beginning is not the same DTMF tones as heard when dialing a phone.

The tones you hear there are the ones which were commonly used for inter-office signaling in the past, and they use a different scheme:

1 = 900 + 700 Hz
2 = 1100 + 700
3 = 1100 + 900
4 = 1300 + 700
5 = 1300 + 900
6 = 1300 + 1100
7 = 1500 + 700
8 = 1500 + 900
9 = 1500 + 1100
0 = 1500 + 1300
KP = 1700 + 1100
ST = 1700 + 1500




[This message has been edited by pauluk (edited 09-21-2003).]

#138591 09/21/03 08:38 AM
Joined: Aug 2002
Posts: 1,081
T
Member
Trumpy:

Also, there were the "MF" (multi-frequency) tones used by the exchange equipment and also an operator could dial them:

Quote
Code
KP=”Key Pulse”
ST=”Start”

DIGIT			FREQ #1(Hz)			FREQ #2 (Hz)
-----      		-----------   			------------
KP			1100				1700
KP2			1300				1700
1			700				900
2			700				1100
3			900				1100
4			700				1300
5			900				1300
6			1100				1300
7			700				1500
8			900				1500
9			1100				1500
0			1300				1500
ST			1500				1700

Here is a small file with MF tones 1 through 0.

[This message has been edited by ThinkGood (edited 09-21-2003).]

#138592 09/21/03 08:55 AM
Joined: Aug 2001
Posts: 7,520
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pauluk Offline OP
Member
TG,
Looks like your post and my edit to include the trunk signaling crossed [Linked Image].

Trumpy,
Before you ask, the Key Pulse and Start signals precede and follow the digits, e.g. to send 1234 the equipment (or operator) would actually dial KP-1-2-3-4-ST.

Compare the tones in TG's link with those you get from a DTMF keypad. The latter are much more dischordant.

In fact the MF trunk signaling tones are quite musical! Download and listen to this file from the Phone Trips website for a little amusement:

MF Boogie

[Linked Image]



[This message has been edited by pauluk (edited 09-21-2003).]

#138593 09/21/03 10:59 AM
Joined: Dec 2002
Posts: 1,253
D
djk Offline
Member
Just on another note there was a possibility that the US and EU DTMF schemes could have ended up being different and incompatable! The in band MF systems used for signalling between exchanges nationally and in some cases internationally in Europe were quite different to those used in North America.

Some of the large EU switch manufacturers considered using their own schemes.LM Ericsson, Siemens, ITT Europe, Phillips and the various UK companies involved in swithc manufacture didn't really have to go with the US system.

However, it made more sense to stick to one way of doing things in the end particularly when DTMF rapidly became a way for customers to control automated services.

Also the A,B,C,D tones are often used by voicemail systems to signal. E.g. when our public voicemail calls the house to notify of a call it signals D between each scentence to ensure it doesn't answer itself! If it answers a call and hears "D" it will cause it to hang up immediately and wait a pre-programmed time before it tries to notify of new messages again.

A,B,C,D also get recognised by our local switches here in Ireland.. You can dial them as part of a number and just get a wrong number announcement once 7 digits are dialled or if you just hit them as a first digit you instantly get a wrong number announcement.

The strangest bit: I accidently dialled an A instead of a 1 (old handset from an office system) after the first 3 digits and it started ringing and was answered as by someone working in an office, apparently it's part of the phone company's internal numbering for calling people in switch rooms from a linesman's phone!

E.g. 555-A will get you someone in the switch that handles 555-XXXX

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