Cytron Technical Forum

Good day.

Currently I am engaging in a projected titled "Wireless automated Taekwondo scoring system" and the proposed system utilizes RF modules for signal transmission. I have a few questions that needs clarification regarding the proposed implementation which I hope can be answered here.

1. Does the receiver chip and the transmitter chip communicate only to each other in a pair or can one receiver chip communicated with multiple transmitter chips?

2. Will the transmitter chip be able to work if I were to connect it to a piezoelectric pad?

The proposed system utilizes piezoelectric pads whereby voltage is generated when a punch/kick is registered. Will the voltage generated by the said impact be enough to power the transmitter? Also, multiple transmitters will be placed into the pads slapped inside the Taekwondo protective gears (trunk, headgear, foot). With that being said, will ONE receiver be sufficient to receive all the signals that are transmitted or do I have to get multiple receivers?

For now, these are my doubts. I hope I can hear some professional advice from y'all here. Please and thank you in advance.

For normal rf u will need to battery power it up. Piezo cant generate stable voltage for the rf

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yonghui WROTE:For normal rf u will need to battery power it up. Piezo cant generate stable voltage for the rf

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Will button cell (batteries used in watches) be sufficient enough to power them? Since I am aiming to keep things as small as possible.

Can, use 2 cr2016 cell or cr2032 cell. Use 2.4ghz rf which running 3.3v http://cytron.com.my/viewProduct.php?pc ... ver%202.4G
Else if u are using low cost rf u will need 2 cell series to get around 6v. Pls turn off the whole circuit and only wake up when ur piezo trigger to save battery life time.

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Sorry. For 2.4ghz wireless use 1cell.

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Another thing is piezo can generate relatively high voltage. U will need to crop it using zener diode

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yonghui WROTE:Another thing is piezo can generate relatively high voltage. U will need to crop it using zener diode

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Instead of using zener diodes, will voltage comparator be suitable as a replacement instead?

Which voltage comparator? U will need to check the data sheet to see the max input voltage. How much max voltage ur piezo will generate when punched?

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this is somewhat a simple function to use but in complex situation. i think there are 2 questions here, related to:-
1. power supply for you rx tx circuit.
2. possibility for multiple tx + single rx.

my opinion:-
1. doesnt matter where you want to put the sensor, you can always use cable, and i recommend li-po battery as it is smaller.
2. possible. i made a project before using rf tx/rx 315mhz. but i recommend you to use newest 433mhz rf from cytron as it data tx/rx is more reliable.