HW_ILoop_Power
... hand trimmed potentiometer for each line
TODO
All teletypes (with current loop interface) are designed for a current of 40mA. The receive unit (magnet coil) has a typical voltage drop of 15V. Taking into account the additional voltage drop in the interface circuits, a power supply voltage of about 20V should do - in theory.
BUT! The switching speed of a magnet coil depends directly on the intermediate circuit voltage - in this case the power supply voltage. On practical experience the intermediate circuit voltage should be at least twice the magnet coil voltage.
ADDITIONAL BUT! Most teletypes are used with a FSG (dialing device). This has also a relay in the current loop with an additional voltage drop. Some relay circuits (especially for "Wahlbereitschaft" = ready for dial) need a higher voltage (60V) to work as expected.
Working supply voltages with interfaces above:
| Teletype | Working voltage |
|---|---|
| Lo15 | 24V |
| T37 | 24V |
| T68 | 24V |
| Teletype | Working voltage | Full Working voltage |
|---|---|---|
| Can transmit, receive and dial but the ready-for-dial-lamp lits always. | Can transmit, receive and dial with ready-for-dial-lamp working as expected. | |
| T37 | 50V | ? |
| T68 | 55V | 85V |
| T100S | 24V | 60V |
TODO More Details...
TODO More Details...
TODO More Details...
TODO More Details...
- Local use
-
i-Telex
- tbd
- Advanced Topics
- Acccess SD-Card from Windows
- Show INET Address in Console
- Off-button for RPi
- Multiple piTelex Instances
- Mail notification on new telex
- Circumvent DS-Lite restrictions
-
TW39 (current loop)
-
ED1000 (FSK modulation)
-
V.10 (TeKaDe FS200, FS220)
-
SEU-M-board based
- with Austrian AGT (Ö-AGT, current loop)
- inside LO2000, LO2001, LO3000 (SEU-B replace)