[VoIP] Audichron information

John Novack jnovack at stromberg-carlson.org
Mon Nov 21 08:21:05 CST 2005

This was sent to the TCI list, in case you aren't on that list
Goes into great detail about the Audichrons


Forwarded to the list and Alan from the non-TCI author:

Dear Alan:

A friend of mine passed along an e-mail you had posted to the Telephone 
Collectors International board.  He also sent along a picture of your 
Audichron machine.

When I got out of college in 1972, my first job was working for 
Audichron in Atlanta.  (Actually, it was in Doraville, but they 
preferred to use Atlanta.)  My job was scheduling the machine shop and 
the Mechanical Assembly department.

The machine you are restoring is called a STM.  Audichron made two basic 
kinds of time announcers: STMs and M-12s.  STM is an abbreviation for 
"Small Town Machine," and STMs were normally installed solely in small, 
rural towns.  M12s were for large cities and had more features than the STM.

The time machine has three drums (not two) that rotate round and round. 
  It also has two sound heads.
Sound head one drops down on the message drum.  "Save by the 10th, earn 
from the first at Central Brevard National Bank.  Central Brevard 
National Bank."

Now sound head number 1 comes up and sound head number 2 drops down on 
the hour record: "Time two."

Sound head number 2 continues onto the minute record "forty two."

Thus the three records give the entire message:  "Save by the 10th, earn 
from the first at Central Brevard National Bank.  Central Brevard 
National Bank.  Time two forty-two."

On a STM, the message record could have (I think) 12 different messages 
recorded on it.  A technician at the phone company had to manually pull 
out a pin on the side of the drum and rotate the drum to a new position. 
  This was done very infrequently (usually for a holiday message) at the 
request of the sponsor.

The M12's message drum had 12 messages, and it could advance them 
automatically on each announcement.  It could also be set to just play 
the same message over and over.

The hour record has just 12 recordings on it: Time one, time two, time 
three, ..., time twelve.

The minute record has 60 recordings: one, two, three, ... fifty-nine, 

The M-12 has TLP, Traffic Load Protection.  During peak call times, the 
machine would automatically shorten the message so more calls could be 

There is a large drum in the middle of the machine.  The drum rotates in 
a bath of automatic transmission fluid to keep it lubricated.  There is 
a groove carved in the surface of the drum.  Some kind of a pin fits 
into the groove and connects to the rod that holds the sound heads. 
This is what causes the rod to move left and right so the sound heads 
can align themselves with the records.  Inside this drum are a complex 
series of gears.  The gears are what cause the three drums to index to 
the proper position each cycle (e.g. change the hour once an hour, 
change the minute record once a minute).

The temperature machine has one recording drum.  There is a lead screw 
on top which holds the sound head.  A thermometer was placed on the roof 
of the telco office in a "birdhouse."  The birdhouse was made of cedar 
(I think) and painted white so it wouldn't absorb heat.  Somehow the 
thermometer was hooked to the temperature machine, and this caused the 
lead screw to turn and moved the sound head over the proper recording. 
(I think it tried to balance resistance somehow.)

The temperature record typically has 140 recordings on it: Temperature 
minus 20, temperature minus 19, temperature minus18, ... temperature 
118, temperature 119, temperature 120.

Periodically, someone from the telco central office has to lubricate the 
surface of the recording drums with silicone fluid.  Otherwise the 
friction from the sound heads would wear away the rubber. (They also had 
to be careful not to get the silicone on the "Hammertone Gray" paint as 
it would eat into the paint!)

Audichron was famous for being able to install equipment in any central 
office in the world.  Every product has options which were referred to 
as "lists."

The basic time machine part number was 5600-L01 [pronounced fifty-six 
hundred list one.]  As I recall there were something like 30 lists: 
5600-L01, 5600-L02, 5600-L03, etc.  Depending on what lists you put 
together, you ended up with unique machines.  You could, for example, 
end up with something like 5600-L01,L03, (2)L07, L29.  (That's just a 
made-up number.)

The Mechanical Assembly department was headed by Elbert Jones who was 
around 60 when I knew him.  It was my job to tell Elbert the kind of 
equipment he needed to assemble by telling him which 5600 lists to 
combine.  By combining different lists, you'd get STMs or M12s or other 
variations of the time machine.  There were lots of variations including 
"Comparator Units" as were found in New York City.  These were hooked to 
an oscilloscope which monitored WWV over the radio and adjusted the time 
automatically.  The Comparator Units has three records just like a 
regular time machine.  However, as I recall, the message record was 
where the seconds were recorded so you got a message like:  "At the 
tone, the time will be one forty-two and 10 seconds."  The tone came 
from a circuit board.  The machine played the records in this order: 
Hour (At the tone the time will be one), Minute (forty two) and finally 
Message (and 10 seconds.)

Interestingly, Audichron made the announcer for the National Bureau of 
Standards to use on short-wave stations WWV in Colorado and WWVH in 
Hawaii.  So, in New York City, you had one Audichron machine listening 
to another Audichron machine in Colorado!

New York City actually had a dual M-12 system.  They rented two machines 
from Audichron because they received so many calls per day.  At 10 cents 
per call [message units], New York Telephone couldn't afford to have 
their time-of-day service go down for a minute!

The temperature announcer was a 5500-L01 with different lists.  You 
could get variations by combining different lists.  For example, I still 
remember machines we built for Parker, AZ and Blythe AZ where the 
temperature scale had to go up to 130 or 140 degrees rather than the 
normal 120 degrees.  We also had to be able to have Fahrenheit and 
Celsius scales.

STM units was normally cabinet mounted.  You have a nice STM cabinet. 
M12s were normally rack mounted.  We made enclosures on which the time 
and temperature machines sat in the telco racks.  We has 19" -wide and 
23"-wide to match whatever the central office needed.

The circuit boards were housed in enclosures that held either 9 or 11 
circuit boards (depending on rack width).  Some of the boards controlled 
the operation of the machine; they would cue the trunks when to answer 
the incoming lines.  Some were alarm cards that reported trouble to the 
central office.  (Look for a red lamp cap with "ALM," that's a major 
alarm.  White lamp caps with "ALM" were minor alarms.)
Most of Audichron machines waited until the beginning of the 
announcement to answer the call.  A few telcos wanted "barge in" where 
the call just started in the middle of the announcement, but the caller 
heard announcement after announcement until he/she hung up.

Audichron has a two man Customer Engineering department (Chris and Jim). 
  These guys worked with each telco on every installation to determine 
what they needed.  The telco would describe their equipment, and the 
Audichron engineers would determine what kind of options and trunks 
Audichron needed to build.

As I recall, Audichron has about 30 different kinds of trunks such as 
Selector Level Digit Absorbing Trunks (SLDATs).  Some of the base 
numbers were: 7300-L01, 7260-L01, etc.   For each main type of trunk, 
there were dozens of options and wiring options that had to be 
engineered to meet each and every central office's needs.  A typical 
trunk might look like: 7300-L01,L03,(2)L05,L20,L23, wrg X,Y,Z,Q.  If you 
pull out a circuit board from your machine, you'll probably see a white 
sticky label on each board that identifies the part number, optional 
lists and wiring options.  You should also find the sales order number 
(e.g., 80-0255 [the 255th order in 1980]) and shipment date.  When I 
started in 1972, a secretary in my office had to type all of these 
labels one-by-one on an IBM correcting selectric typewriter!

We had two people who were known as "talent." They came in on a 
part-time, as-needed basis to do recordings.  Of course, you know Jane 
Barbe.  The male was John Doyle who was the weatherman at Channel 2 in 
Atlanta.  Jane would come in a couple of times a week to make message 
records for new installations.  She would also make new message records 
whenever an end-user (i.e., bank) wanted some kind of new message.  Once 
a year, Jane would come in to make new "master" hour and minute 
recordings to "keep them fresh."

An Audichron installer installed each new system in the telco central 
office.  He worked with telco installers in the central office.  After 
the technician went home, it was up to the telco employees to maintain 
the machine: lubricate the records, add transmission fluid, change the 
message records when their customer (e.g., the bank) wanted them 
changed, adjust the machine for daylight savings time twice a year, etc. 
  Audichron's customer was the telco.  The telco's customer was the 
bank.  Audichron leased the machine to the telco, and the telco leased 
it to the bank for a higher monthly fee.

Of course all of the above was before deregulation.  Deregulation 
changed everything and was actually the end of the mechanical time and 
temperature announcers.  (Another long story!)

I have attached a photo of the original painting that was reproduced as 
a full page in the December 1972 issue of Esquire Magazine.  The article 
was about Audichron and Jane Barbe.  Thought you would find it amusing. 
  (Let me tell you, the management at Audichron did not like the article 
one little bit!!!)


Hope I haven't bored you too much.  You brought back a few memories!

Charlie Myers
Portland, Tennessee

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