Panels made in metal case with bench support and the electrical scheme on the front panel. The board shall consist of PSK (Phase Shift Keying) modulator and demodulator sections that can be interconnected in order to simulate a complete transmission system.

Technical Features:
The board shall use the support board as a service module to provide the carrier signal, the modulating random digital signal, the error rate meter and the line simulator.
Phase inverter modulator and adjustable frequency PLL demodulator, followed by low-pass and squarer filter.
Power supply: ± 15 Vdc, 50 mA and + 5 Vdc, 200 mA

Theoretical Recalls:

• The meaning of numerical modulation
• Classification of the modulation methods
• Phase Modulation
• Binary Psk Modulation (bpskl2psk)
• Multiphase Modulation
• Coherent Psk Demodulation (c-psk)
• Differential Biphase Coding

This panel shall contain the following elements:

• NRZ encoder: it shall encode the TTL level signal coming from the auxiliary generator of the support module into signals having bipolar NRZ line code.NRZ encoder: it shall encode the TTL level signal coming from the auxiliary generator of the support module into signals having bipolar NRZ line code.
• DPSK encoder (Differential PSK): it must be possible to used it for the study of this type of coding.DPSK encoder (Differential PSK): it must be possible to used it for the study of this type of coding.
• Duo-binary encoder: it must be possible to used it for the study of the operation of the PSK partial responseDuo-binary encoder: it must be possible to used it for the study of the operation of the PSK partial response transmission system.
• PSK modulator: this functional block shall be  preceded by an adjustable phase shifter to align the carrier phase with the one of the modulating digital signal. This is useful in certainexperiments.PSK modulator: this functional block shall be  preceded by an adjustable phase shifter to align the carrier phase with the one of the modulating digital signal. This is useful in certainexperiments.
• The modulator shall operate on digital signals and it will be therefore unprovided with a modulation depth control. The carrier will be dephased of 180 degrees for positive inputs, of 270 degrees for Zero input and 0 degrees for negative inputs.
• Receiver: composed of an intermediate frequency amplifier (IF), with carrier regeneration circuit.
• Demodulator of coherent type: that shall use the regenerated carrier in the same circuit IF. The phase of this carrier will be adjusted to receive the better demodulation conditions.
• Reception carrier regenerator: this circuit shall be based upon a PLL whose free oscillation frequency will be very near to the one of the transmission carrier and that locks to this signal when it is present. To make its use easier there shall be  a LED that switches on when the regenerated carrier coincides with the transmitted one.
• NRZ decoder: that shall accept in input the signal produced from the coherent demodulator and it shall operate in base to a timing generated in the receiver from the clock regenerator. The NRZ decoder shall be equipped with a variable decision threshold used internally to distinguish between the logic levels of the received signal.
• Duo-binary decoder: it shall allow to study the operation of the partial response PSK system. The circuit shall use the clock provided by the regenerator circuit of the receiving section and it shall be equipped with a manual drive DECISION POINT to determine the level recognition thresholds.
• DPSK decoder: it shall be the circuit having the function that is complementary to the transmission encoder one. It shall be connected to the output of the NRZ decoder and to the clock regenerator for the timings.

With this panel it must be possible to perform the following exercises:

• Operation of the panel DL 2563
• PSK system with NRZ line code
• DPSKcoding
• PSK system with partial response coding
• PSK system with NRZ code in presence of transmission noises
• PSK system with partial response coding
• In presence of transmission noises