RF module false triggering relays (home automation)

I’m struck at a point in my home automation project.
I’m using 4 channel 433MHz receiver and transmitter remote for controlling 4 channel relay board.

4 outputs of rf receiver are directly given to 4 inputs of 4 channel relay board. Both are given common dc 5v power supply.

The problem is, when I start the dc power supply to system, all relays are triggered once automatically without pressing any key on rf remote.

What could be going wrong? Any idea?
( I am thinking on using some pull down or pullup resistors before relays)Anyone please suggest.

( Exactly same problem is arising with pir sensor also)

Dnyaan:
4 outputs of rf receiver are directly given to 4 inputs of 4 channel relay board. Both are given common dc 5v power supply.

So just to confirm, no Arduino in the mix?

it sounds like you are getting a voltage spike at startup

you need to delay sending signals to the relay until after that spike

neiklot:
So just to confirm, no Arduino in the mix?

neiklot:
So just to confirm, no Arduino in the mix?

No arduino. Just rf module and relay board.

I want to do this without using any microcontroller. It should Ideally work, the way i did it. Any other suggestions?

The problem is using the same power supply for the relay board and the receiver board.
Power up the receiver board first, and then after a short delay , 1 -2 seconds should do , power up the relay board.

mauried:
The problem is using the same power supply for the relay board and the receiver board.
Power up the receiver board first, and then after a short delay , 1 -2 seconds should do , power up the relay board.

Could you suggest any way to implement this without using any microcontroller?

A time delay relay?

So till now I have figured out that it has nothing to do with relay.

I have removed the relay board and used multimeter to measure the output from rf receiver board. It is giving 3.3 volts everytime I power on the supply.

Same thing is happening with the pir sensor module, it also gives 3.3 volts at output, everytime I power on the supply.

Not sure what is happening behind this. Please suggest.

Dnyaan:
Could you suggest any way to implement this without using any microcontroller?

Why do you want to implement a home automation system without using microcontrollers ?

srnet:
Why do you want to implement a home automation system without using microcontrollers ?

Because that's the main objective of the project.

I've been biting my tongue but have to ask: why are you asking this on the Arduino forum, in boards under the heading "Using Arduino"?

Dnyaan:
Because that's the main objective of the project.

But why, is this a real project or something given to you as an exersize by a college or similar ?

neiklot:
I've been biting my tongue but have to ask: why are you asking this on the Arduino forum, in boards under the heading "Using Arduino"?

Because I know it will be done by using arduino. But the thing is I want to do it without arduino. Being an engineer we should be able to make it work by both the ways.
And here, I believe that there has to be some way to make it work.
(I believe Arduino is an easy solution to any problem which I don't want to go for)

Perhaps what you want to do can be done without an Arduino: who knows, you haven’t painted the big picture. But that’s not my point.

My question is, why are you asking how to do something specifically Arduino-free, on a Using Arduino forum?

(Not that I’m one of those “HEY! You mustn’t ask non-Arduino questions here” guys. But let’s say Ford have a range of off-road vehicles, and you want to do the Darien Gap on foot… would you expect Ford to tell you how?)

Your logic doesn’t make sense: I could do it with Arduino, I don’t want to use Arduino, so I’ll ask how to do it Arduino-free on an Arduino forum.

neiklot:
Perhaps what you want to do can be done without an Arduino: who knows, you haven't painted the big picture. But that's not my point.

My question is, why are you asking how to do something specifically Arduino-free, on a Using Arduino forum?

(Not that I'm one of those "HEY! You mustn't ask non-Arduino questions here" guys. But let's say Ford have a range of off-road vehicles, and you want to do the Darien Gap on foot.... would you expect Ford to tell you how?)

Your logic doesn't make sense: I could do it with Arduino, I don't want to use Arduino, so I'll ask how to do it Arduino-free on an Arduino forum.

Brother, if it is bothering you, please ignore it.
I'm looking for a solution to a real problem.
One who has any idea will respond, you can ignore. Thanks.

It's not bothering me that you post here, at all: if anyone has an answer, I'm sure they will be glad to assist.

It's your logic that's bothering me: I'm just curious as to why you're posting here.

maybe because... who uses this stuff?

( hand waving in air ): I know, teacher! Arduino guys!

neiklot:
It's your logic that's bothering me: I'm just curious as to why you're posting here.

The OP made the reason clear;

"Being an engineer we should be able to make it work by both the ways"

So appartently the volunteer Arduino microcontroller engineers that inhabit these forums should also be able and willing to provide help to prove that what would normally be done with a microcontroller (and for very good reasons) can be done without.

I dont get it either.

Have you read the datasheet for the decoder chip thats being used on the receiver board.
Reading datasheets is always useful when things arnt working properly.