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Extend a wireless door bell. Current distance is about 160m open air. Answered

I am looking at extending the range of a wireless door bell. I currenly have a range of about 160m open air but would like to make the distance longer. Does anyone know how to do this? Do I mod the transmitter and the receiver?



7 years ago

hi all
plz help me out as soon as possible

i hav a wireless video door phone with 2.4ghz n in build antenna
the prob. is i having the distance of around 300 mtr n there is two many wall in between n i cant see the peson standing in front of the camera basically the range prob. can any 1 help me to increase range..ail me on md.ali@live.in

have you tried extending the internal antenna (although that might change the frequency it ll receive.

Remove the SPEAKER from the doorbell.  extend the wire from the doorbell to the speaker located REMOTELY.  Now the doorbell receiver can be placed close enough to receive the signal... but the actual tone is sent down the wire to the remote location.  Thats LOTS easier than trying to boost the power of the transmitter or other complex hacks. 

If you can find the antennas you can try to add length to them. Depending on the design and the freq. that might work.

Agreed. Longer antennas. If you know what frequency the doorbell uses, you can even tune the length of the antenna to an even multiple of the wavelength...

Silly question but how is it possible to measure the freq of the door bell, I do have an option to tune the Transmitter. And if I have the Freq how to calculte the antenna?

 Heh, You could use a spectrum analyzer, but that's not exactly within the price range of mere mortals! I was hoping it would say what frequency it's operating at on the unit or on the package. Have a closer look, it ought to be there somewhere. I suspect it's 27MHz, 49MHz or 900MHz...

Whatever the frequency is, invert it to get the wavelength in meters. Then multiply the wavelength by a power or two (4, 8, 16, 32, 64, etc).

There's a whole lot more to antenna design that I don't know (indeed, one could make it a career!) but that should get you most of the way there.

Hi Jeff, thanks for the tips, a spectrum analyzer well your right a bit out of the price range.

I think the Freq is 27MHz, how do I invert this and calculate the formular? Sorry but being dumb at this, its been awaile since I was in school.

I read some where that adding a 7cm antenna to the Inductor would extend the range, but it did not work so well the distance became less. I guess the Freq changed.??

Any suggestions.



Normally, an antenna should be one half of the wavelength.<br /><br />speed of light= frequency * wavelength<br /><br />3*(108)=27*(106)*wavelength<br />Length=11.11meters<br /><br />~5.55meter antenna<br /><br />It's a long wire, but hey, it might work stapled to a tree or something. <br /><br />A better option might be trying to just add more power (ie batteries). it might fry something, but then again, it might not!