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nrf24l01 Amplification

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nrf24l01 Amplification

By steven7777
-  Tue Oct 09, 2007 8:54 am #36184
I'm sending data back and forth around a room, but when I move one of the NRF24L01's to behind a wall and change the orientation of the antenna, I stop receiveing data, or it becomes very erratic.

I notices the following setting: LNA Gain. Should this be a 1 or a 0? I see the default is 1. Which will give me more sensitivity and therefore more range? 1 or 0?

I am trying to get hold of the MAX2240 so that I can amplify the RF signal. My aim is to get about 100mW of output power. I am not in the USA. What would you recommend I use to get more power? What kind of range would the MX2240 give (estimate).

By brennen
-  Tue Oct 09, 2007 10:10 am #36190
The LNA gain bit wasn't described much in the original datasheet, but if you get the new one, Nordic actually does mention it. For best reception, you want it set, but if you clear it, you get less gain at the receiver but the trade is that your power consumption goes down. I haven't dealt with power amps for the 24L01 chips, so I can't help you on that, but there has been some discussion of this recently on the forum, so a quick search should turn up some info.

By tastech
-  Tue Oct 09, 2007 8:17 pm #36212
You mention you are not in the US, but not where you are. The EU is more limiting than the FCC with the allowable output power. In many cases you are limited to +10dBm so your 100mW may be too much.

Various countries all have different constraints placed on what you can do in the ISM band. Information is not too hard to find but most of the standards can be a bit tough to grasp due to the wording and different classes.

By lucicop
-  Tue Oct 09, 2007 11:08 pm #36219
I think 0db is the limit for 2.4GHz band. You should have at least 10m inside, even through walls. With external antenna on both sides, you should have even more...

By steven7777
-  Wed Oct 10, 2007 5:28 am #36225
I have the bit set, and it the comms become very erratic or non-existent after about 10 feet and behind a wall. Is it supposed to be this low powered? I was hoping to transmit stuff around a house at least.

I have ordered samples of the MX2240's, but where can I get hold of the RF Switches?

By steven7777
-  Wed Oct 10, 2007 5:53 am #36227
The one I'm using is on the PCB. It looks almost like a hook. A diagonal track coming out of the chip, then a 45 degree bend and another 1cm, then a 90 degree bend and another 1.5-2cm. Is this the horrible one you mentioned?

What would the expected range be for the above?

What would the expected range be for the external better one?

By lucicop
-  Wed Oct 10, 2007 6:12 am #36229
The reference boards from Nordic look like steven described it. I also use some of these and the range is not very brilliant. Yet, with one PCB antenna and one SMA antenna I was able to get 5m behind 2 walls :) Try with two devices each with SMA antenna.

By steven7777
-  Wed Oct 10, 2007 6:26 am #36230
It is the same as you describe it. I have noticed that the main thing that effects it is the orientation of the antenna. If they're both aligned the same, and it is line of sight, then it transmits much further.

The test I did was hanging it outside my window and trying to get it to communicate with the one next to my PC. The distance between them was about 10 feet. There was a wall and a PC metal case in between.

I am thinking about cutting the antenna track, and putting a straight vertical pin perpendicular to the board.
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