Circuit for the obtaining of a continuous feeding from the telephone line current (Machine-translation by Google Translate, not legally binding)
ES8800552A1
Improvements in exclusion circuits associated with parallel-connected telephone devices
ES8708107A2
Improvements introduced in the purpose of pat. principal n.536.269 for "new system of simultaneous communications of voice and data with possibility of connection to public or private networks.
ES8705646A1
Improved procedure for aligning and focusing fiber optic terminations with lens
ES8705638A1
A direct current generator-drainer with null insertion losses.
ES8703220A1
Fibre=optics communications system receiver - forwardly biasses PIN=diode when light signal is received to act as transducer
ES8700517A1
New variable capacity coded pulse modulation equipment (mic)
ES8700515A1
Feedback control circuit for sigma-delta modulator
ES8701443A1
Telecommunications switching system
ES8702758A1
Procedure to isolate an incoming direct subscriber in a telecommunication center
ES8608255A1
Malicious calls detector device for multifrequency keypad subscribers
ES8603134A1
Simultaneous voice and data communications system
ES8604379A1
Circuit for feeding test tables in telephone centers
ES8601630A1
Conductive coating applicator for ceramic substrates
ES8606965A1
Electronic relay for direct current
ES8601593A1
An electrical converter system
ES8503140A1
Improvements in the control of light sources for optical communications
ES8502589A1
Electronic circuit for telephone line taking
ES8502588A1
Testing device for switching equipment in telephone stations
