VM130, periodic failure

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1

For a couple of months I have used a VM130 Two Channel RF Remote Control Set for switching on the garden light in my driveway. But there is a problem with the system. Sometimes it is functioning very well, but at other times it is not functioning that well. When it is functioning very well, I can switch on the light from a distance of 30 – 40 meters, when it is not functioning well, the distance is reduced to 1 – 3 meters. I have tried the following measures:

  1. Changed the battery in the transmitter and checked the red LED is flashing when a button is pushed
  2. Change the power supply for the receiver from a 12V DC power supply to a 11V AC power supply
  3. Moved the antenna, which was fastened to a wood board, to a location clear of any material. The receiver is elevated about 1,5 meters over the ground, there is free sight from the transmitter to the receiver, and there is no houses, cars, electronic devices etc. near the site
  4. Connected the two NO relay contacts in parallel, so I can use both channels for the same task
  5. Checked the wiring

My experience is that when I at night approach my driveway in my car at a distance of about 30 meters, I push a button on the transmitter mounted with Velcro on the sunshield above the windshield. The garden lights are switched on. This will be repeated for some days. Then one night the light does not switch on. I step out of the car and push a button on the transmitter for at least 2 seconds. Then I release the button, walk a couple of steps towards the receiver and try again. This I repeat until the light switches on. Then I am only about 2 meters from the receiver. After the light is switched off I repeat the walking process starting from a distance of 30 meters. The light switches on immediately with no problem.

By the way, when the system is idle only the red LED for channel 2 is on, never the red LED for channel 1. Is this normal?

Any ideas of how I can make it functioning every time I push a button at a reasonable distance?

2

It is normal that only 1 LED on the receiver is on all the time.
The problem you experience can have different causes.
Differences in temperature or humidity can influence reception.
VM130 is equipped with internal heating that can be selected by placing the jumper.
External radiation sources can influence reception (transmitters, wireless thermostats, weather stations, other 433MHz equipment, power lines, cellphone antenna’s, etc…
Try finding the exact cause of troubles.
You could also try relocating the receiver.

3

Thanks’ for your answer. The internal heating jumper is in place. Do you have a suggestion on how I can find external radiation source, if any? I do have other 433MHz equipment myself, that are not disturbed – and are normally turned off, when I am not at home, so they cannot be the culprit :wink:

4

This will be very difficult to determine, since you do not have any measuring equipment and the problem is not always present.
First, you need to determine if the problem is caused by the transmitter or receiver.
You can only do this if you have a second remote.
Some other things to try:

Check if the problem also occurs if the garden lights are not connected to the relays of the VM130.
Check if the problem occurs if the VM130 is fed with a 12V battery.