RF receiver / transmitter problems

[kenman12]

Sample circuit view 2

two.jpg (93.58 KiB) Viewed 424 times

I I ordered 2
Simple RF T4 Receiver - 315MHz Toggle Type PID: 1097 https://www.adafruit.com/product/1097
and a single
Keyfob 4-Button RF Remote Control - 315MHz PID: 1095 https://www.adafruit.com/product/1095#technical-details

I was trying to use it with a circuit I had designed but was getting no joy.

I then setup the circuit in the video with 4 LED's and 4 1 k Ohm resistors. I checked the power to the board and see that the chip is getting 5 V. When I pull the board off my circuit and put a new one back I get one of the LED's to flash. I checked each LED and each works with the 1 K Ohm resistor when I apply 5 V. So I know the LED's are working.

When I press the transmitter buttons A,B,C or D then the transmitter led comes on RED. Nothing happen on the board. I removed the LED's and measured the voltage at the D0,D1,D2 and D3 and none of them change voltage. So either the transmitter is not transmitting or the reciever is not recieving. Both of the Boards I purchased exhibit the same behaviors.

Do I have to use Pullup resistors? Your page seems to indicate I do not. If not any other troubleshooting tips or do I have a bad board / reciever?

[adafruit_support_bill]

Pullups are not needed. But you do need to uncoil the wire antenna.

[kenman12]

should the antenna be completely straight or as close to straight as possible?

[adafruit_support_bill]

It doesn't need to be absolutely perfectly straight.

[kenman12]

I unfurled the antenna and it does not work. I tried both receiver modules it does not work. I measure no voltage change when I press the buttons on the transmitter. Any further suggestions?

Also if unfurling the antenna is required might want to put that on the product page and show it unfurled in your video.
Thanks,

[adafruit_support_bill]

We can try replacing the transmitter/fob. Please contact [email protected] with a link to this thread.

[fujito]

Can I use these set of receivers to switch 12 VDC LEDs on and off?

I am trying to control (on/off) 3 12 VDC LEDs with this device. I have separate 5 VDC and 12 VDC power sources. Attached is the wiring diagram for my set up.

When wired as shown, all LEDs turn on.. as 12 VDC is delivered to all of the LEDs but there is no on/off control of the individual LEDs. Ie, nothing happens when I depress any of the buttons on the transmitter. I was expecting that the receiver would act like a relay and connect the common ground to the LEDs.

I read somewhere in the comments that the common connection on the 5 VDC supply should be put on the + side of the power supply. When I do this, the voltage delivered to the LED's is 4.6 VDC when the the channel is on, and 4.4 VDC when the channel is off. The LEDs have a significant change in brightness when I do this. This does illustrate that the transmitter and receiver are talking.

Any help would be appreciated.

[adafruit_support_bill]

The outputs of these modules are logic-level signals. They are not relays. They are only designed to handle a few mA at 5v. Wired as shown, you are likely to destroy the device.

To control a high-voltage and/or high-power device, you can use the output of the module to turn on a transistor or relay to switch the current.
https://learn.adafruit.com/rgb-led-strips/usage

[fujito]

Since I will not be using these devices, please cancel order #2592585-3180650309, which is a reorder of the T receiver and an order of the M receiver. They are in processing and have not yet shipped.

[adafruit_support_bill]

You can try contacting [email protected] with a link to this thread with your cancel request. Generally, once orders are pulled for packing, they cannot be cancelled.