It is a case of function over form - the two telephones that serve me well and should live on after the introduction of the national FTTH communications network known as the NBN thanks to a device that converts decadic pulses to DTMF tones that will be recognised by the next generation of telephone exchanges.

This wall phone is in my kitchen and is connected to the second phone line, which I use mainly for receiving calls and Internet usage. That phone line also feeds the web server that hosts Vintage Radio and Television.



The table phone above is in the lounge room next to my Airzone console radio. It is the phone I make most calls on, not that I make many these days.

It is a testament to backwards-compatibility that modern digital telephone exchanges still support decadic (pulse) dialling, which is required for these phones to work correctly.

These telephones were made by Amalgamated Wireless Australasia (AWA) but also made by Standard Telephones and Cables (STC).

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A valve a day keeps the transistor away...

The dial on your 400AW wall phone has been specially calibrated, given what's on the label. It makes me think this phone has been used for exchange testing. Or the dial has been retrieved from something that was.
Just for your interest, the letter prefixes as shown on the 400AT table phone's dial were obsolete ca. 1962, although many continued to use them for years after.
Incidentally, on the base of these phones is the year of manufacture. On the later 800 series plastic "Colourfones" one can also check the cord grommets for the year - but this applies only to the cords - one way to tell if a phone was later reconditioned (yes they did recondition most phones when taken out of service, contrary to now it's just put in the garbage).
There were several reasons for dropping the letters; one being due to the introduction of seven digit phone numbers (i.e. three digit exchange prefixes) in the early 60's.
The PMG realised rude words would be spelt with certain prefixes, eg, if your exchange prefix was 379 or 276.
The other reason was that they actually tested the dialling speed of people using letter prefixes and numbers only. They found people tended to pause slightly with the letters. With three letters instead of two the time taken to dial a number was even slower.

Good point with the letters. I gathered for a second that 27-6379 was the phone number for the local shimmy palace.

On a more serious note the new toll-free numbers that accomodate lettering nowadays is something I find confusing to the extend you mentioned. I can dial a phone number blindfolded if given the digits but if the number includes letters then forget it.

One other thing is that the letters that are on the keys now don't correspond with those on old phones so if I used the lettering in a toll-free number on one of my vintage phones I'd be calling the wrong number.

Things were much simpler with 6 digit phone numbers I reckon. Far easier to remember and less wear and tear on the dial.

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A valve a day keeps the transistor away...

Hi Brad

I have an old farmhouse up north which I've managed to stuff with all manner of weird and interesting things. I recently replaced the modern digital phone with an ivory PMG bakelite phone that I've had for years. Not only can it be heard from all parts of the property (and neighbour's properties I suspect) but it doesn't need to be plugged into the power. I remember growing up with these phones as a kid and still recall our first number: YU 3262. The only downside is that the handset gets heavier and heavier with a long phone call. Small price to pay.

It's nice to know that the old technology still has a part to play.

Cheers
Mark

It makes me wonder if AWA and STC manufactured any phone cabinets in odd colours on an experimental basis. I've seen black, ivory, red and green though the latter three colours were on phones made much later than those I have (I'm not sure of model numbers or any similar details) and if such cabinets were made then have they survived somewhere.

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A valve a day keeps the transistor away...

Good question. I haven't seen any other than black.

Cheers

Mark

Griffin: still recall our first number: YU 3262

Was that the Bankstown region?

South Granville. It is a much different place now.

Mark

Not too far off then. I'm wondering if you meant UY (i.e. 70) which I very vaguely recall being Bankstown/Punchbowl area.

Perhaps you're right. It was a long time ago. 70 sounds more likely than 07 doesn't it?

Very nice shiny Telephones you have there Brad, I found this site on how to keep them shiny,

http://www.britishtelephones.com/bakelit1.htm

...and on the restoration and and cleaning of Bakelite cased telephones and also Bakelite radio cases.

Thought it may help you guys in your restoration projects.

Nobby.

I was lucky with the table phone - it came out of the box brand new in 1987! I still remember cutting the packaging tape on the box and this was about a year before I officially bacame a radio collector. I think I was 16 at the time.

How a government-issue telephone can remain idle in someone's shed unused for around 30 years and then get sold at a school fete still in its original packaging has got me baffled.

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A valve a day keeps the transistor away...

It was amazing what us old PMG types got upto, Anything for a quid.

The association of letters with telephone numbers has a long history. When exchanges were all manual, numbers were listed in alphabetical order under the name of the exchange such as Moe, Moore, A. 7. So a caller would ask the operator for Moe 7. If the number was on a party line, then a letter suffix was added to indicate the particular subscriber, ie Vermont 12M.

When the first Strowger automatic exchanges were established in the late 1890s, they had less than 1000 lines and used three digit numbers. By 1906 the exchanges were much larger and used four digit numbers. An unknown 'expert' at the time declared that nobody would be able to remember more than four digits so prefix letters would be needed for a five or six digit number. This 'fact' was accepted without question and repeated in a range of American, British and Australian technical documentation for the next 50 years.

There two technical problems that had also become apparent. First there was a practical limit on how large (in terms of the number of lines connected) an exchange could be given that there was a physical restriction on the length of the line between the subscriber’s telephone and the exchange. (The longer the line the greater the resistance plus line inductance and capacitance caused signal attenuation and distortion.) Therefore there would need to be multiple exchanges installed across a city with junction lines interconnecting each exchange to all the others. This meant that there would have to be some way for callers to automatically select the exchange that served the subscriber they wanted to speak with. The way to do this was to allocate a one, two or three digit numeric code for each exchange this code was added as a prefix to the subscriber’s phone number. However this then meant that the phone number would be longer than four digits so various sets of nine or ten letters were allocated to the digits 1 to 0. I have a technical book written in 1914 by two staff of Automatic Electric in which they detail how a Step-by-Step switch network of main exchanges should be established with junction lines interconnecting them and recommend a set of letters that were phonetically distinct to identify each exchange. A main exchange could also have up to ten satellite exchanges connected to it. Each main exchange was allocated a single letter and each satellite exchange was allocated two letters but the first letter was the same as its main exchange. The PMG used this network scheme and accepted the suggested letters with just two differences. The final set of letters used was ABFJLMUWXY. Note that the codes did not spell any exchange name. So using the phone number that Mark remembered (proof that the alphanumeric scheme worked), YU3262, his phone was connected to a satellite exchange with the letter code YU with and the main exchange would have been Y. (Actually the 'real' phone number would have been 073262 and the phone would have been connected to Level 6, Position 2 on the banks of the final selectors in the exchange.) The PMG used this scheme with some modifications until 1958 when planning was undertaken for the introduction of Subscriber Trunk Dialling (STD). For STD to work a two or three number prefix would be required making numbers up to nine digits so consideration was given as to the best way to print long numbers in telephone directories. As Cool386 said, trials made by people dialling test phone numbers with letters and others that were only digits showed that an all digit number was faster. Also by then most people could easily memorise seven digit numbers plus an STD code prefix. Letters were dropped and consequently the 801AT released in 1962, had only numbers on the dial.

Although the Strowger/Automatic Electric scheme worked well in Australian cities, it had limitations that restricted its use in very large cities such as New York and London. In 1918 a three letter scheme was devised for use with the Panel switch that Western Electric developed to service greater numbers of lines that could be practically handled by a Strowger Step-by-Step switch. The scheme allocated three or four letters to each of the digits 2 to 9. (The digit 0 was reserved for Operator/Long Distance and for technical reasons no number started with 1.) Each exchange (or Central Office as they were called in American practice) was allocated a name and the caller actually spelled out the first three letters of the name as a prefix. In the directory a number was printed with the first three letters in capitals, eg GARfield 1234. To call that number a caller would dial 4271234. That 1918 letter scheme lives on and is now the international standard used with your mobile phone.

In Britain, ATM which was the British affiliate of Automatic Electric developed the Director system which added the three letter exchange name facility to Strowger Step-by-Step switch but they allocated the letters O and Q to the digit 0. There was a unit at each exchange that used relay logic plus what we would now call a ‘look-up table’ to decode the first three digits dialled and then select a junction line to the required exchange. The remaining digits dialled were passed through a Relay Set Repeater over the junction line. This process could result in a delay of 30+ seconds after dialling before the called number started to ring.