I agree with Chuck here. I personally don't like antennas spec'd at 6dB
beamwidth.

On Wed, Apr 11, 2018 at 10:43 AM, <ch...@wbmfg.com> wrote:

> 6 dB == half the range for an antenna if you are presuming a certain fade
> margin.  .
>
> Path loss = 96.6 + 20 log F + 20 log D
> F is frequency in GHz, D is distance in Miles.
>
> If you say 1 GHz (for simplification) and 1 Mile path loss is 96.6 dB:
>
> At two miles it is 102.62 dB.
>
> At 3 dB down the range has decreased by 70%
>
> I think a beamwidth showing 70% to 100% range is more useful and honest
> than 50% to 100%.
> In other words, 3 dB down in receiver voltage is within the normal daily
> fluctuations.
> Not going to make or break a connection.
>
> 6 dB down is significant and could cause trouble.
>
>
> *From:* Mathew Howard
> *Sent:* Wednesday, April 11, 2018 9:29 AM
> *To:* af
> *Subject:* Re: [AFMUG] Rfelements
>
> I'm not sure if the RF Elements horns are rated at 3db or 6db, but I know
> RF Elements list the beamwidth at both points for their normal sectors
> (which is the best way to do it, if you ask me). It seems to be a lot more
> common these days to use the 6db beamwidth for marketing purposes, but I
> think there are actually some valid reasons for doing that - if the
> manufacturer is recommended that you use antennas that are 90 degrees at
> -6db, rather than -3db for an ABAB deployment, for example (which is the
> case, with some of them, if I remember correctly), then it makes sense to
> sell those as a 90 degree antenna, so that the people that don't bother to
> check things like that don't buy the wrong antenna.
>
> On Wed, Apr 11, 2018 at 10:21 AM, <ch...@wbmfg.com> wrote:
>
>> Speaking generally here, not about this product specifically:
>>
>>
>> A 30 is a 30 at some dB down from peak.  Most reputable antenna
>> manufacturers cite the beamwidth at the 3 dB down points on each side of
>> the main lobe.  That is called HPBW or half power beam width.
>>
>> Some go out farther to the 6 dB point to make their beam width seem wider
>> than their competitors.  Personally I believe that is false advertising.
>> But I am sure they do not share my opinion.
>>
>> Look at the type of beamwidth.  Should state how many dB down somewhere
>> on the spec sheet.
>>
>> Other than that, horn antennas are very well characterized.  They are
>> used as lab standard calibration antennas.  Other than the point where they
>> choose to specify the beamwidth I think you can totally trust the specs.
>>
>> *From:* Steve Jones
>> *Sent:* Wednesday, April 11, 2018 9:01 AM
>> *To:* af@afmug.com
>> *Subject:* Re: [AFMUG] Rfelements
>>
>> so if im getting the right feel, here, I CAN trust these spec sheets? a
>> 30 is actually 30 and not 90? FB is real?
>> Ive had two in play on EPMP1000 for some time but i keep pulling them and
>> moving them elsewhere because of changes, so Ive never had one up long
>> enough to see. I have use case for narrower patterns and more APs at some
>> sites because the uplinks are getting more interference than id prefer, my
>> only other option is to add the secondary antenna on the 2000, im not a fan
>> of adding windload with no net capacity gain
>>
>> On Wed, Apr 11, 2018 at 9:57 AM, Steve Jones <thatoneguyst...@gmail.com>
>> wrote:
>>
>>> we have a substantial garbage dump
>>>
>>>
>>> On Wed, Apr 11, 2018 at 9:08 AM, Jaime Solorza <
>>> losguyswirel...@gmail.com> wrote:
>>>
>>>> There's mountains near Steve's WISP footprint?
>>>>
>>>> Jaime Solorza
>>>>
>>>> On Wed, Apr 11, 2018, 7:45 AM Mike Hammett <af...@ics-il.net> wrote:
>>>>
>>>>> You have that the other way around. A horn would be ideal in a
>>>>> mountain area.
>>>>>
>>>>>
>>>>>
>>>>> -----
>>>>> Mike Hammett
>>>>> Intelligent Computing Solutions <http://www.ics-il.com/>
>>>>> <https://www.facebook.com/ICSIL>
>>>>> <https://plus.google.com/+IntelligentComputingSolutionsDeKalb>
>>>>> <https://www.linkedin.com/company/intelligent-computing-solutions>
>>>>> <https://twitter.com/ICSIL>
>>>>> Midwest Internet Exchange <http://www.midwest-ix.com/>
>>>>> <https://www.facebook.com/mdwestix>
>>>>> <https://www.linkedin.com/company/midwest-internet-exchange>
>>>>> <https://twitter.com/mdwestix>
>>>>> The Brothers WISP <http://www.thebrotherswisp.com/>
>>>>> <https://www.facebook.com/thebrotherswisp>
>>>>>
>>>>>
>>>>> <https://www.youtube.com/channel/UCXSdfxQv7SpoRQYNyLwntZg>
>>>>> ------------------------------
>>>>> *From: *"Sean Heskett" <af...@zirkel.us>
>>>>> *To: *af@afmug.com
>>>>> *Sent: *Tuesday, April 10, 2018 10:49:19 PM
>>>>> *Subject: *Re: [AFMUG] Rfelements
>>>>>
>>>>> I Totally agree with josh.
>>>>>
>>>>> They have a specific purpose so if you can deploy within those
>>>>> parameters they are great.
>>>>>
>>>>> Unfortunately our area isn’t conducive to that type of deployment
>>>>> because of terrain.  In the mountains you need antennas with a wider
>>>>> vertical beam because your towers are on mtn peaks and some clients are
>>>>> same height as the tower and other clients are on the valley floor.  It’s
>>>>> hard to use a spot beam to cover all that.
>>>>>
>>>>> In the Midwest or other flat areas I could see them being useful to
>>>>> spot beam the population centers.
>>>>>
>>>>> -Sean
>>>>>
>>>>>
>>>>> On Tue, Apr 10, 2018 at 8:29 PM Josh Reynolds <j...@kyneticwifi.com>
>>>>> wrote:
>>>>>
>>>>>> They are great for stuff like 30/40Mhz wide, gps sync, put 4-6 on a
>>>>>> pole in a subdivision  or on a tower leg kinda thing.
>>>>>>
>>>>>>
>>>>>> If anybody thought they were for something else (ie long range), they
>>>>>> didn't read the data sheets.
>>>>>>
>>>>>> Lightweight, low size, low wind load, perfectly circular pattern -
>>>>>> great spot beams. Good F/B ratio.
>>>>>>
>>>>>> On Tue, Apr 10, 2018, 9:12 PM Robert <i...@avantwireless.com> wrote:
>>>>>>
>>>>>>> I recently did a couple of tests with RF horns.   I was hoping for a
>>>>>>> lot
>>>>>>> and was disappointed.   I was hoping that they could be colocated
>>>>>>> closer than regular sectors that I use and the crosstalk signal
>>>>>>> levels
>>>>>>> were just about the same as the shielded sectors.   As far as the
>>>>>>> signals at the CPE's they were pretty good but not amazingly better
>>>>>>> for
>>>>>>> as small as the target area got reduced to.
>>>>>>>
>>>>>>> On 4/10/18 6:43 PM, Steve Jones wrote:
>>>>>>> > Can i get some non fanboy real world on these guys? Btw, i hate
>>>>>>> facebook
>>>>>>> > groups almost as much as dslreports or the ubnt forums, this is
>>>>>>> > literally the only place to get legitimate product info.
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>>
>
>

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