Currently trying to construct an RF Receiver and Transmitter circuit, however I've run into a little hump.

What I am expecting to happen is, the LED in the receiver circuit should turn on when the switch in the transmitter is pressed.

However, I'm observing the opposite. That is, the LED is on and when the switch is pressed, it turns off.

Is there some way of reversing this so the opposite happens?

RF Receiver and Transmitter on breadboard

RF Reciever schematic

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    \$\begingroup\$ First step would be to make that schematic big enough we can read it. ANd what is the IC? \$\endgroup\$
    – Trevor_G
    Mar 15, 2018 at 19:50
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    \$\begingroup\$ There are a pile of other things that you need to consider when using these simple tx and Rx devices. Oh well! \$\endgroup\$
    – Andy aka
    Mar 15, 2018 at 19:56
  • \$\begingroup\$ The IC is a voltage regulator. Taking 12V and outputting 5V. As well, opening the image in a new tab provides a better view of the schematic. \$\endgroup\$ Mar 15, 2018 at 19:59
  • \$\begingroup\$ No I mean the big block in the middle of the schematic. Anyhow, try flipping the LED around and going up to Vcc through a 330R or so resistor. \$\endgroup\$
    – Trevor_G
    Mar 15, 2018 at 20:01
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    \$\begingroup\$ What is the big IC - U1? \$\endgroup\$ Mar 15, 2018 at 20:01

1 Answer 1


Try it this way.. R1 Should be ~330R for 5V.

enter image description here


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