Hi all
New to electronics and need some help! Ive done a lot of research and need some help with a one-off project.
I purchased an RFID reader from eastern Australia for a mountain bike race. The unit works fine, but the rider has no indication of a successful RFID read apart from a small onboard LED that would be in a unit anyway.
So I want to convert this only indication of a successful RFID read to another external brighter LED and audio response, to assist the rider when a successful RFID read has occured.
So I soldered a little white cable off the onboard LED to try and get a voltage. The multimeter gives me some erratic reads, but I think its around 50mv when the LED lights up.
My first attempt was a simple NPN transistor circuit with a LDR for the switch. I had varied results, but didnt really work out (I think) due to the low voltage and speed of the LED pulse.
My next several attempts over several days involved a 555 circuit, to try and extend the output time using a cap and transistor to get the desired 1secound output. Some involved using the LDR, some the cable off the onboard LED but nothin seems to work.
Currently (as shown in the attached images), but setup sort of works. Again, much like the NPN setup, the speaker outputs such a short pulse that the speaker is almost inaudible.
So if anyone has any suggests, please fire through! Getting to the end of my tether
I think i firstly need some help in terms of getting a consistent read from the onboard LED. The LDR had trouble detecting such a quick pulse. If anyone has any other suggestions in getting another signal from the purchased board, that could also greatly help.
*sorry about the hair on the breadboard! haha*
Kind Regards
Steve
New to electronics and need some help! Ive done a lot of research and need some help with a one-off project.
I purchased an RFID reader from eastern Australia for a mountain bike race. The unit works fine, but the rider has no indication of a successful RFID read apart from a small onboard LED that would be in a unit anyway.
So I want to convert this only indication of a successful RFID read to another external brighter LED and audio response, to assist the rider when a successful RFID read has occured.
So I soldered a little white cable off the onboard LED to try and get a voltage. The multimeter gives me some erratic reads, but I think its around 50mv when the LED lights up.
My first attempt was a simple NPN transistor circuit with a LDR for the switch. I had varied results, but didnt really work out (I think) due to the low voltage and speed of the LED pulse.
My next several attempts over several days involved a 555 circuit, to try and extend the output time using a cap and transistor to get the desired 1secound output. Some involved using the LDR, some the cable off the onboard LED but nothin seems to work.
Currently (as shown in the attached images), but setup sort of works. Again, much like the NPN setup, the speaker outputs such a short pulse that the speaker is almost inaudible.
So if anyone has any suggests, please fire through! Getting to the end of my tether
I think i firstly need some help in terms of getting a consistent read from the onboard LED. The LDR had trouble detecting such a quick pulse. If anyone has any other suggestions in getting another signal from the purchased board, that could also greatly help.
*sorry about the hair on the breadboard! haha*
Kind Regards
Steve
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