Arduino Forum

Using Arduino => Networking, Protocols, and Devices => Topic started by: Siddesh_8134 on Apr 16, 2019, 07:01 am

Title: HC12 Range Issue
Post by: Siddesh_8134 on Apr 16, 2019, 07:01 am
Hi all,

      I'm using HC12 for my project.At first i was getting quiet a good range, but now im getting few meters(testing in the same place) when compared to last.So please help me with where im doing wrong and where is the issue?

Another query is which factors affects the range and im using FU3 mode with 2400 Baud rate(Spring Antenna).

Thanks,
Siddesh
Title: Re: HC12 Range Issue
Post by: srnet on Apr 16, 2019, 07:39 am
At first i was getting quiet a good range, but now im getting few meters(testing in the same place) when compared to last.So please help me with where im doing wrong and where is the issue?
So what did you do between when the modules were working well and were not ?
Title: Re: HC12 Range Issue
Post by: Siddesh_8134 on Apr 16, 2019, 07:45 am
Nothing.Now Modules are working perfectly for shorter distance but not for longer distance. I have 5 modules,all are behaving in the same way...
Title: Re: HC12 Range Issue
Post by: srnet on Apr 16, 2019, 07:59 am
Nothing, really ?

Then assume one of the HC12s is now faulty.
Title: Re: HC12 Range Issue
Post by: Siddesh_8134 on Apr 16, 2019, 08:20 am
Will Check it out each.Is there any possibility that individual module is good at transmission or reception like that!?(after using module for few days)

Thank you for suggestion,
Siddesh
Title: Re: HC12 Range Issue
Post by: Geek Emeritus on Apr 16, 2019, 06:02 pm
Quote
(Spring Antenna).
the mantra of RF guys: solve RF problems with antennas first. they are cheap, they are easy, and they produce the greatest effect for the least cost and effort

433 mhz is also a ham band. googling 70 cm antenna will keep you busy all day.

homebrew antenna projects (https://www.dxzone.com/catalog/Antennas/70cm/)

short and simple:
one to one, fixed locations, use directional gain antennas on both ends
one to many, fixed locations, use an omnidirectional antenna on the one end and directional on the many
one to any, mobile, useomnidirectional antennas

the easiest omnidirectional gain antenna to build and use is the collinear. good for up to 15 db of gain. anyone claiming more has knowledge of the laws of physics he is not sharing, or he is a liar

the benefits of gain antennas work equally well on both ends of a link. if you stick up a 15 dbi gain antenna, every link gets 13 db gain over a standard issue 2.14 dbi gain dipole, on both ends
Title: Re: HC12 Range Issue
Post by: Paul_KD7HB on Apr 16, 2019, 07:15 pm
the mantra of RF guys: solve RF problems with antennas first. they are cheap, they are easy, and they produce the greatest effect for the least cost and effort

433 mhz is also a ham band. googling 70 cm antenna will keep you busy all day.

homebrew antenna projects (https://www.dxzone.com/catalog/Antennas/70cm/)

short and simple:
one to one, fixed locations, use directional gain antennas on both ends
one to many, fixed locations, use an omnidirectional antenna on the one end and directional on the many
one to any, mobile, useomnidirectional antennas

the easiest omnidirectional gain antenna to build and use is the collinear. good for up to 15 db of gain. anyone claiming more has knowledge of the laws of physics he is not sharing, or he is a liar

the benefits of gain antennas work equally well on both ends of a link. if you stick up a 15 dbi gain antenna, every link gets 13 db gain over a standard issue 2.14 dbi gain dipole, on both ends
I built the 9db collinear antenna years ago. Still have it. Worked Great!

Paul
Title: Re: HC12 Range Issue
Post by: srnet on Apr 16, 2019, 08:40 pm
The OP reported initially getting good range with the spring antennas, but then they stopped working so well in the same location, with no other changes.

Switching to higher gain antennas, might well improve the situation, but fixing the actual problem, whatever it is, should return the spring antennas to their previously acceptable performance.   

Title: Re: HC12 Range Issue
Post by: mauried on Apr 16, 2019, 11:16 pm
Interferance could also be a problem if you live in suburbia.
Try changing the radio channel and see if range improves.
It helps a bit when trying to debug these types of problems if you can listen on the frequency you are trying to use.
I use an old hand held scanner for this, and the amount of stuff that uses these frequencies is immense.
Title: Re: HC12 Range Issue
Post by: Siddesh_8134 on Apr 19, 2019, 07:05 am
Hi,

  Sorry i was out of station so i didn't reply. The only thing that got changed while testing is a neighborhood 1 floor building is demolished and they are building a new one of 4 floors.

When the old building was there i was getting good range(keeping transmitter in our building). But in new one I'm not getting range even in our building(which i was getting earlier).

I will test in different place confirmation. But I'm interested to know which are the factors affecting the range.Is it a New building or something else!?

Thanks,
Siddesh   
Title: Re: HC12 Range Issue
Post by: srnet on Apr 19, 2019, 01:53 pm
The only thing that got changed while testing is a neighborhood 1 floor building is demolished and they are building a new one of 4 floors.

When the old building was there i was getting good range(keeping transmitter in our building).

But in new one I'm not getting range even in our building(which i was getting earlier).

  
So despite 'Nothing' changing between getting good range and bad range, it now appears you were testing in different buildings ?

Quote
I'm interested to know which are the factors affecting the range.
All the things that you include in 'Nothing' ?

Title: Re: HC12 Range Issue
Post by: Siddesh_8134 on Apr 20, 2019, 07:00 am
Hi,

    No i'm not testing in a different building.I'm testing in a same building which i tested before.The only thing changed is neighbour's building.
 
    I thought it is not affecting the range, because i'm not getting communication within our building only(which i was getting earlier). So i was so confused what may be the reason!? Is it that building affecting communication or any other factor!?

Thanks,
Siddesh
Title: Re: HC12 Range Issue
Post by: srnet on Apr 20, 2019, 07:56 am
Ultimately the forum cannot tell why your modules are not working as you expect. Trying to work out what may be different in a building is probably a waste of time.

You need to test and compare how your various modules perform in uniform conditions, a large open space for instance.

With a decent spectrum anlayser you can measure what is going on in the lab.
Title: Re: HC12 Range Issue
Post by: Siddesh_8134 on Apr 20, 2019, 08:46 am
Ultimately the forum cannot tell why your modules are not working as you expect. Trying to work out what may be different in a building is probably a waste of time.

You need to test and compare how your various modules perform in uniform conditions, a large open space for instance.

With a decent spectrum analyzer you can measure what is going on in the lab.
Ok sure will test modules in uniform conditions. Thank you for your suggestions.

Thanks,
Siddesh
Title: Re: HC12 Range Issue
Post by: Siddesh_8134 on Apr 24, 2019, 06:56 am
Hi,

   I've one doubt about HC12, will the module get affected(range or data loss) as we use regularly 5v as Vcc!?

Thanks,
Siddesh