Advance Electronic Industries

Bhandup West, Mumbai, Maharashtra

adtrons 7520-21 is an advance digital communication trainer system that helps one understand various

digital modulation and demodulation techniques. various functional block diagrams are provided on-board as an aid for

teaching/training. these kits are provided with various test points to visualize the signals on oscilloscopes. all ics are

mounted on ic sockets. bare board tested glass epoxy pcb is used. attractive wooden enclosures of light weight pine

wood.

features:

3 on-board sine-wave generator

3 on-board four carrier sine waves of 500khz

3 on board three nos. of 8-bit nrz-l. data simulator.

3 clock frequency of 250 hz.

3 data format (coding) is nrz-l, tribit encoded and differential encoded i & q bits

3 receiver clock generated by pll method

3 demodulation is done using pll and envelop detector method

3 switch faults are provided to study its effects on circuits

3 block description screen printed on pcb

3 in-built power supply

technical specifications

3 carrier sine wave generator : 1. four carrier sine waves generated onboard.

2. provides synchronized sine waveform output of 500 khz (0 deg.),

500 khz (90 deg.), 500 khz (180 deg.), 500 khz (270 deg.)

3 clock and data generator : 1. 24 bit variable nrz-l pattern generated depending on the position of

the three nos. of 8-dit data switch provided

2. clock frequency is of 250 khz.

3 data format (coding) : 1. non return to zero-level (nrz-l).

2. tribit encoded data (i , q & c).

3. differential encoded i & q bits.

3 carrier modulation techniques : 1. quadrature amplitude modulation.

2. differentially quadrature amplitude modulation.

3 carrier demodulation techniques: 1. quadrature amplitude demodulation.

2. differentially quadrature amplitude demodulation.

3 on-board features : 1. on board three nos. of 8 bit variable nrz-l pattern data simulator

2. switch faults are provided on board to study different effects on

circuit

3. qam/dqam demodulation using pll and envelop detectors

4. switch faults are provided on board to study different effects on

circuit3 interconnections : 4 mm sockets.

3 test points : 32 aprrox.

3 power : 230v + 10% 50 hz, 1 ac.

3 accessories : a. detailed instruction manual.

b. set of patch cords.

experiments:

1. to study the elements of 8-qam / dqam system.

2. tribit coding & decoding technique of nrz-l data format.

3. differential encoding & decoding of data.

4. 8-qam modulation & demodulation technique.

5. dqam modulation & demodulation technique.

6. to study of constellation diagram of qam.

7. to study bandwidth efficiency in qam & 8-qam/dqam techniques.

8. effect of switch faults.

9. observation of constellation diagram.