Antennas and pigtails for BPI-R3

Hello, few days ago I have received BPI-R3 a now I am looking for pigtails and antennas for it. It would be great to get some advices from experienced users.

Best pigtails length? 8x15cm? 4x5cm and 4x15cm? Any other length combination for “cable management”?

How about antennas? I have read somewhere that it is better to choose single band antennas instead of dual band. Available options that I can get fast in my area:

2.4GHz 5dBi (2400-2500MHz) - Antsym

2.4GHz 8dBi (2400-2500MHz) - Antsym

5GHz 5dBi (5150-5850MHz) - Antsym

5.8GHz 8dBi (5725-5850MHz) - Antsym

2.4/5GHz 5dBi (2400-2500MHz and 5150-5850MHz) - ALFA Networks ARS-NT5B

2.4/5GHz 5dBi/7dBi (2400-2500MHz and 5150-5850MHz) - ALFA Networks ARS-25-57A

What would you recommend from this list? Or maybe there are some reliable sellers on Ali or Ebay to buy from?

Pigtails: I tend to use RG178. It is about the thickest cable that is feasible to use with U.FL connectors. I find it’s got the best loss characteristics while still being flexible enough to use. I recommend for each radio to use four cables the same length - this helps with beamforming. I keep a lot of 20cm cables since I find they are a good general purpose size for these types of cases. If you have all 2.4G antennae on one side and 5G antennae on the other, then you can prolly get away with four of the cables being shorter 10-15cm cables. I get them from this vendor on Ali Express and have never had issues:

Antennae: I tend to use dual band dipoles. If they are properly made, you don’t lose a lot with them being dual band. That said, I’m not terribly impressed with the specs on the ARS-NT5B above. It’s lowest SWR is very low in the 5GHz band. I prefer a basic 1.75/.75 wave end-fed dipole (See How to mount the antenna to the box). It will tend to have the lowest SWR at around 5.7HGz and 2.45GHz. I have two devices in my home that use these really cheap antennae: though I still recommend you use the pigtails above. The pigtails that come with these antennae can be kept and used when you want to test multiple cards or something (since you have a limited number of connect/disconnects on a U.FL end).

Are you sure sma female are right? My antennas have female,so pigtail has to be male

If you’re buying both the antennae and the pigtails it doesn’t matter, since you can get what matches. Personally I use SMA reverse polarity. RP-female for my pigtails and RP-male for antennae, since this matches what Netgear uses and that is what I started customizing years ago. The antennae I linked above are RP-male.

Just not buy 30cm cables. I bought 8 30cm rg178 and now I have huge “cable-mess” inside router case:) And rg178 are not too flexible. They are holding in u.fl for now, but I dunno, maybe they will disconnect, because of tension.

If one disconnects, it may cause a short circuit is you’re unlucky. Who knows what will be the damage.

I used a bit of glue from glue-gun on the cable (not connector) to take away the tension.

What exactly speaks against the official Antennas?

I ordered the Antsym 5ghz antennas, I ran some iperf3 tests from a ~15m distance. you can see the improvement from the dual band antennas

Dale, was it these

5GHz antennas

Been trying to find suitable ones for ages.

Exactly those. I even left a review there

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Anyone replace the antennas with one of the below?

I found these 10dbi antennas I might give them a go. image

Although these 8dbi antennas also appear to work. image

These 15dbi antennas might just be what I go with! image

Can someone share why one of the above is better or worst for the R3? The ones posted above are only 5dbi and yet its listed as 5150-5850MHz and I am wondering does this range reflect what works best for the R3?

You could use a coat hanger and it will “work”. It just will not be efficient. The dual band antennas, generally only work at the lower frequency & use a quirk to operate at the higher frequency. In doing so, they become less efficient due to the higher frequency being roughly double the lower. That 600-6000MHz antenna should be regarded as snake oil.

ohh tell me more, why snake oil?

Thanks for the Antsym 5GHz recommendation. Which Antsym antennas did you use for the 2.4GHz bands?

I haven’t ordered 2.4GHz antennas from them. Unfortunately they don’t ship to my country anymore

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