[Mesh] pallet of high gain (11dbi) directional wifi antenna's up for auction

[Jake]

Martin,

a diplexer is a device to feed one antenna from two transcievers, since it
splits signals according to their frequencies.

https://en.wikipedia.org/wiki/Diplexer

you might be thinking of a splitter.

John, i have a really nice 2.4GHz directional coupler by Narda, it has four
ports unlike the slightly similar one in this picture:

http://www.recycledgoods.com/media/catalog/product/cache/1/image/1000x/af097278c5db4767b0fe9bb92fe21690/n/a/narda-microwave-corp.-3002-30-coaxial-directional-coupler-2.0-ghz-1.27.jpg

you can borrrow it if you want, I also have attenuators and stuff like that.

-jake

On Thu, 3 Nov 2016, Martin wrote:

> 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-Direc
> tional-Coupler-ZADC-13-2000-1-13dB-SMA-50-Ohm-NEW-/291379146
> 740?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 at 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 at 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 at 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
>>>> _______________________________________________
>>>> mesh mailing list
>>>> mesh at lists.sudoroom.org
>>>> https://sudoroom.org/lists/listinfo/mesh
>>>>
>>>
>>>
>>
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>>
>