RFM12pi ... Change Mhz

Hardware
1

Hello.

I got a RFM12pi board as a gift. RFM12Pi V2 - OpenEnergyMonitor Wiki
Atm the RFM12pi is setup for 868Mhz.
Any way to change the MHZ to 433Mhz?

What i found is… Home | OpenEnergyMonitor
Looks like the difference is a capacitor … Is known what value this capacitor has?

Thanks a lot for any hint.
Christian

2

You can force it in software to run at 433Mhx by setting frequency in emonhub.conf or issuing 4b serial command manully. Range will be reduced significantly since the antenna system is optimised for 868Mhz. I’m not sure if it’s possible to change the hardware without chaning the module.

3

I’m reasonably certain that it’s not just that one capacitor that’s different, so it is necessary to change the module. (There are posts about this in the old forum.)

1 Like
4

Thanks a lot for this information. So i have to look for a 433Mhz Board :frowning:

5

It’s worth trying the software method, I have several modules I have ‘forced’ to work at a differant frequency working fine in my (small) house. Just depends on the range you require.

I’m sure you will be able to sell the 868Mhz unit if you post it up in the ‘For Sale’ section of the forum. The 868 unit will be in high demand since we have stopped producing 868 to standardise on 433.

6

Christian, I’ll swop it for a 433Mhz RFM12pi if you’re interested?
I’ve got a brand new 433Mhz RFM12Pi sat in my workshop, and my emon system is 868Mhz.

If you are interested, please PM me.

Paul

7

@glyn.hudson.

My house is also not so big. So I’ll just test it with the 433 mode. Thanks for the hint.

@Paul:
Thanks for the offer. If I am not happy with 433 I will contact you via PM.

Christian

1 Like