Telexforum.de

Hello,

the Lithium battery is 1/2AA 3,6V with axial wires:

https://www.reichelt.de/de/en/lithium-b ... os_1&nbc=1

In a previous post, Henning mentioned that this particular machine has a double current interface. +/- 60 volts, 20mA
I never heard about such an interface before
Could you please advise on:

• How the two current loop should be connected to the ADo-8 connector?
• How the control signals are implemented in this case? Compared to TW39 for example.
• Can such machince connected to the i-Telex network via the HW offered on the website or via Pi-Telex interface?

Yesterday, I made a little experiment:
1: I created a single current loop: 24V 16.5mA
2: Connected this loop to the machine via ADo-8 pin 1 and 4: Pin 1 is (+) Pin 4 is (-)
3: Nothing visible happens, and only 0.8 mA flows trough the circuit
4: I switch the polarity: Pin 1 is (-) Pin 4 is (+)
5. Machine now starts, the led next to the disconnect button turn on, and there is a 7.8 mA current flowing trough the circuit

Further observations:
- Machine remains on despite I terminate the current loop
- Machine remains on despite I change the polarity again
- Machine remains on despite I press the the disconnect button on the machine
- Machine can only be turned off by removing it from the mains circuit
- Pin 2 and 3 was not connected during the experiment.

Double current is also a four wire connection, so two wires are dedicated to the "sending" and two to "receiver" circuit.
Normally 1-2 ist one circuit and 3-4 is the second. Which is send, wich receive? I don't know. Simply measure the voltage across 1-2 and 3-4. That pair with "resonable" voltage is the sending circuit.
But what makes me wonder is the fact that you mention that when 2-3 is open the machine "reacts" on polarity change on 1-4.

Connect a current loop source with a polarity-reversal-switch to the OTHER (receiver) connectors.
When you change the polarity, the machine should start and stop.
In "On" position you should be able to produce random character printing by QUCKLY switching the polarity.
Wenn the teleprinter is "running" you can measure the voltage on the sending circuit (preferable by an oscilloscope). When hitting keys you should see also polarity changes on this circuit. Check if the typed characters are also printed or not. (*)
When the printer is idle, please check if the polarity on the "sending" circuit also changes if
a) "normal" keys are hit
b) the "start-button" (dot within a circle) is pressed.

(*) If the typed keys are NOT printed, you may do another test: Connect 1-3 and 2-4 an see if the typed characters are printed.

Regarding the i-telex: There is a prototype double current version interface board available, but the software is not finished yet. If the above mentioned tests are successful we can discuss about the possibilities to finish the development of the double current i-telex interface.

Hello levend,
here some more hints to bring up your T1000S...
(By the way, what's your real given name? )

1. Lithium battery / NiMh accu

The Li-battery only buffers the customer memory (one static RAM IC) which contains the identification and some other programmings.
Other memory Chips and RTC are buffered by the NiMh-accu....

So, if you didn't disconnect the battery substitute yet, you can try to read the identification:

Switch the machine to programm mode (P-button+paper feed), then type "22"
(This function works without service plug)

If an identification is stored the result looks like this:
+++++++++++++++++++++++++++++++++++ +++++++++++++++++++++++++++++++++++

When replacing the batteries, be sure to check whether the ON/OFF-switch works reliably.
Sometimes corrosive vapors from the batteries cause malfunctions.

2. Service plug

Here my solution:
+++++++++++++++++++++++++++++++++++ +++++++++++++++++++++++++++++++++++

3. Timer Function

Your T1000S has a switch with a clock symbol on the left switchboard.
This switch usually is implemented if the machine was used with permanent connection and represents a timer-function.
++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++++++++++++++
Translation:

Timer ON/OFF
With permanent connection (fixed line to a remote station) the timer switches the T1000 S
off if within a certain time neither characters are sent nor be received.
The indicator lights up when the timer is turned off, i.e. when the connection remains.

So, don't push the timer switch and wait a while, machine should switch off after about 3 to 6 minutes.

4. Line interface, connection

First of all here some pictures to understand single an double current connection:
+++++++++++++++++++++++++++++++++ +++++++++++++++++++++++++++++++++
In other words, at single current the character cuts of the loop current, at double current it changes polarity.

As you can see in the circuit diagram, receiving and transmitting loops are totally separated, i.e. when using double current you always need two wire pairs! I think they should appear at pin 1+2 (Rx) and 3+4 (Tx) of the ADoS8, or the other way round, I dont know!
And, if it is a double current interface, you should mesuare a voltage of about 60V at either pin 1+2 or pin 3+4!
In this respect, the behavior of the interface is a bit strange because a current is flowing, when the voltage is applied to pin 1+4.
Can you write with printing when the 7,8 mA currentflows?

From my point of view it looks like a single current interface, because if muliplying your values by 5 you get following results:

24V x 5 = 120V
0,8mA x 5 = 4mA
7,8mA x 5 = 39mA

And these are the values of a single current interface (120V, 5mA standby-current and 40mA working current)...
Increase voltage or standby-current carefully to 4 or at least 5mA, than change polarity and wach what happens!

Best regards

Hello Ranier and Fred!

My real name is Balazs already updated my signature to reveal myself

Service plug: I'm using a simple jumper wire to connect pin1 and pin 20 - it working perfectly. Most probably I will update it a plug like you showed - still need to buy a connector.

Identification: I used an arbitrary value, as the batteries were long gone by the time I got the machine. This is how it looks now: Please let me know if you see any problem here.

Kind of interface this machine has:Thanks for all the tips! As Fred suggested, I made a few measurements:
No current loop was inserted to the machine. I just pressed the online button(dot in a circle)

Voltage between pin 1-2: 0V
Voltage between pin 2-3: 0V
Voltage between pin 3-4: 0V
Voltage between pin 1-4: 0V
So it's not a double current loop interface. Let's continue with the experiments: I built the circuit where I can switch the polarity by a switch, and increased the current to 20 mA. Now the machine is turning on and off. I can even use the disconnect button on it! By breaking the circuit I was able
to print random characters - a fantastic feeling. Tomorrow my order with optocouplers/transistors will arrive so I can start building an RS232-TW39 interface.
Until that I verified the following scenarios manually:
- Send message to the device
- Dialing a number from the device
- Sending message from the device
- I was even able to send some prestored message but the logic is still unclear to me - more experimentation to come.

I would like to thank all of you your help, finally I feel I'm on the right track.

Hello Balazs,

the identifier usually has 20 characters and conventionally starts with "CR", "NL" and "Figs", as you can see in my example.
Or "Figs" in the very first place, last character should be "Letters".. Using this pattern the identification is always printed at the beginning of a new line.

The service plug needs a 32-pin socket wich is difficult to find.. I used one with 34 pins and cut two...
You can find such sockets at the "Reichelt-Company":
https://www.reichelt.de/de/en/sockets-2 ... GE=EN&&r=1

The interface in your T1000S obviously is a 40mA current type, as shown by your measurements and experiments...
So you should bring the current up to 40mA by both increasing the line voltage and choosing the correct value of the current limiting resistor in the line circuit.

To check if the machine can be used with the TW39-interface of i-Telex proceed as follows:

- Bring machine in stand by modus: pin1 (+), pin4 (-), current about 5mA
- Push call-button, current shoud go to about 40mA
- Now DON'T change polarity, but interrupt the circuit for 10-30ms This brings T1000S to dial-modus, LED call button lit and if you now dial with the figure keys, cut-off-pulses are sent
In this modus all other keys are disabled.
- Now change polarity: The machine will change to write-modus, LED finish-button lit, an acoustic signal sounds wich shows that
connection to the remote subscriber is established

If this procedure is successful I'am sure your T1000S will work perfectly with the TW39-interface of the i-Telex system and also with an appropriate PI-Telex unit.

Did you check the timer function?

Unfortunately the documents about the T1000S are in German language and scanned as "graphic", not OCR..
So, if you need some assistance with translations or more details about running/repairing the T1000S feel free sending an e-mail to
my address shown in my signature below...

Best regards
Rainer

Following international rules the ID has to start with LTRS in any case, even when the real ID starts with FIGS. But more important is CR LF at the beginning!

see this old topic:
https://telexforum.de/viewtopic.php?f=2 ... eber#p2524

Your interface board looks like double current since everything is double (2 transistors, 4 optocouplers etc.) but maybe it is universal to use
and it can be configurated also for single current operation.
Double current telegraph lines are basically like a high level/high voltage RS232.

I reprogrammed the ID based on the ITU standard document, now it looks like this: Henning, it's entirely possible that the card in the machine is a universal single/double current one since it has 2 DIP switch, so some configuration is possible.

Ranier, the dial-modus/write-modus functionality based on how you described it is working perfectly. Now I'm working to connect it to a microcontroller.
So far I did not check the timer functionality, that's still on the list.

Dear forum members, finally an update after 7 months - I managed to construct a piTelex interface, and use it as an interface for my T1000S. Now I started working on discovering the software, so far the basic functionality is working fine - I can send and receive messages both from the raspberry pi and from the telex. Discovering how dialing works will be the next.

To allow dialling other i-Telex (and piTelex) users, the hostnames of the subscriber servers must be specified (provided that they are not already defined in the default ("factory") configuration.