John,

The coupler you got is probably a diplexer - a device to feed two antennas with one cable.

To do the testing that you're thinking of requires a directional coupler like this: http://www.ebay.com/itm/Mini-Circuits-Coaxial-RF-Directional-Coupler-ZADC-13-2000-1-13dB-SMA-50-Ohm-NEW-/291379146740?hash=item43d78ceff4:g:A0IAAOSwqu9U2rgN  The seller claims that the units were tested to 2800 MHz and worked.  This is a pretty good deal.

For the noise source you can use one of these: http://www.ebay.com/itm/DC-12V-0-3A-SMA-noise-source-Simple-spectrum-external-tracking-source-DY2-/172150915301?hash=item2814fe80e5:g:OaUAAOSwI3RW-t7N

You don't need a spectrum analyzer - a Hack-RF or similar SDR will do.  Connect the noise source to the directional coupler input and the antenna to the coupler output.  Attach the SDR to the coupler's coupled port.  With your favorite SDR software tune your radio to mid-band (2.442 - 2.447 GHz).  Note the receiver power level.  Reverse the antenna and noise source, repeat measurement.  The larger number is the power delivered to the antenna, the smaller is power reflected back from the antenna.  You can use an online calculator like this http://rfcalculator.mobi/vswr-forward-reverse-power.html to calculate VSWR.  The ideal VSWR is one and an antenna with greater than three should not be used.

Although the antennas are only rated to 2.2 GHz they may be usable at 2.4 GHz.  Check the VSWR.

The antennas are probably useful for hams (there's a 902.005 MHz through 927.995 MHz band).  I can ask around and see if there's is any interest.  You might want to put one one ebay and see if there's a market.

--Martin


On Thu, Nov 3, 2016 at 1:14 PM, John Fitz <johnfitzeecs@gmail.com> wrote:
Dang, well I picked up the pallet of antennas and it looks like they're the CELLMAX-EXT-CPU which only cover 806–960 MHz and 1710–2200 MHz :( . Hey but on the plus side, they contain tee couplers that are rated for the full 698–960 MHz and 1710–2700 MHz. I've needed a 2.4Ghz coupler for a while now and that alone was worth the minimum bid for me. With one of those, a noise source and a spectrum analyzer, I can start characterizing Wifi/Bluetooth antennas.
The antenna design is relatively simple and pretty cool looking. It would be interesting to try and simulate the design and see how much would have to change in order to extend the range. Also, if anyone wants to build a phase arrayed radar system...


On Fri, Oct 28, 2016 at 6:57 PM, Marc Juul <juul@labitat.dk> wrote:
Are you sure these cover 2.4 GHz. There are multiple versions of the CELLMAX-EXT and e.g. the CELLMAX-EXT-CPU seems to not cover 2.4 GHz while the CELLMAX-EXT-CPUSE does cover 2.4 GHz:

  http://www.commscope.com/catalog/wireless/product_details.aspx?id=151

  https://www.tessco.com/products/displayProductInfo.do?sku=396652

if we're sure they cover 2.4 GHz then we'd love to get them! I'd pay up to $100 in that case

On Fri, Oct 28, 2016 at 4:55 PM, Jake <jake@spaz.org> wrote:
pallet of high gain (11dbi) directional wifi antenna's up for auction:
https://www.auctionbdi.com/listings/details/index.cfm?itemnum=1158888078

Fitz says they can probably be won for $25 and i think he's willing to bid on them for sudomesh

so if sudomesh wants them, they should tell Fitz how much Sudomesh will pay for the lot.  140 pounds of antennas.

Fitz, did you have a datasheet on these antennas?  I believe i recall they were wideband in the 900MHz and 2.4GHz bands?


-jake
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