This is the info that came with the circuit enter image description here enter image description here enter image description here I am in no way experienced or knowledgeable with circuits or electronics passed installing my own car subwoofers and amps, or swapping out pickups on a guitar which means I only basically know how to solder.

I want to make sure that I wasn't going to blow myself up, or the chip that I've been checking the mail every day for 30 days to get to me from China.

I have a circuit that does not require any power. I just need it to open and close. Not introducing any power into that circuit that's all I want to happen. I can do this by just having a gap in the circuit and touching each side of a wire to bridge the gap.

Now I want to make it so that same simple bridge happens from a button I press.

After researching I think I have the right parts, I got an RF receiver and transmitter that are both 315 MHz. (receiver is pictured) it is powered by 3 V-12 V (I will use 9 V).
I just wanted to make sure that this circuit wasn't trying to send the 9 V through the circuit. I want it to just open and close an external circuit.

This one says it has 0 V output which seems to be what I'm looking for.

Anyone have tips on how to wire this thing up to do what I need or am I not even using the right parts?

  • \$\begingroup\$ I'll be honest, a board that has typos in a picture instead of detailed documentation on what it does (a datasheet) is really not the easiest to deal with. Where I am (Germany) it would be definitely illegal to operate this device – 315 MHz is in no unlicensed band, so you need to go to your radio spectrum authority and buy a license to that spectrum (which is probably impossible). So, sorry, not going to help you wire up that thing which might put you into legal trouble (or, frankly worse, disturb the operation of potentially critical systems at 315 MHz). \$\endgroup\$ – Marcus Müller Dec 19 '18 at 11:03

The pictorials at the bottom of your question shows how it is wired. Supply the receiver with an appropriate voltage. 3rd from the bottom shows it simulating a momentary switch.

It appears to have an AMS1117 type of semi-LDO regulator so more than 5V would be appropriate given the 4.5V relay coil.

If you get the power polarity wrong, even briefly, it will almost surely destroy the receiver instantly.

The three connections go to a mini signal relay type UD-2.

"ON"(sic) means "Normally Open"

"COM" means "Common"

"NC" means Normally closed, which you probably don't need.

Between "COM" and "ON" is a contact (effectively a switch) that is normally open and closes when the relay is actuated. No voltage is output, according to the diagram shown.

Do not use the relay to switch mains voltage. If the device you are controlling is connected to the mains without isolation, even though it is switching a lower voltage, you may create a safety hazard with respect to the isolation between your supply and what the relay is switching. For example, a switch in a mains-powered device that lacks galvanic isolation between the switch and the mains could potentially put mains voltage on the power supply leads, particularly if it got wet. There are insufficient PCB clearances for such an application regardless of the relay rating. Seek qualified local advice if mains voltage (or more than about 24V) is involved anywhere in the circuit.


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