But in the case of dual chain radios, is what Ken said correct, that one
signal at 0db amounts to the same thing as two at -3db? If that's the case,
there wouldn't seem to be any interference rejection advantage to dual
slant over dual linear, regardless of what polarity the interference is.

On Wed, Mar 25, 2015 at 2:55 PM, Chuck McCown <[email protected]> wrote:

>   Depends on which chuck you mean....
> Slant helps with multipath.  Linear to slant rejection is only 3 dB.  If
> your interference is dual pol linear, you have two choices:
> Stay linear with a different frequency and hope for the best.  Or use dual
> slant for a 3 dB reduction of the interfering signal.  Better than a poke
> in the eye with a sharp stick.
>
> But if you are only running one single chain/radio and the interference is
> on the same frequency, orient your antenna 90 degrees to the interference
> and you will get 20+ dB of rejection.  Irrespective of the absolute
> polarization.  If they are +45 make yours –45 etc etc.
>
>  *From:* Jeremy <[email protected]>
> *Sent:* Wednesday, March 25, 2015 1:47 PM
> *To:* [email protected]
> *Subject:* Re: [AFMUG] AF5X polarization
>
>  Yeah, I knew about the multipath advantages.  It seemed to me that 3db
> of rejection would increase your CINR by 3db.  Am I wrong here?  Chuck?
>
> On Wed, Mar 25, 2015 at 1:44 PM, Mathew Howard <[email protected]>
> wrote:
>
>>  I'm not sure that it really gains much if anything as far as
>> interference rejection... I've read that even though the interfering V/H
>> signals are going to be 3db weaker, you're now going to be seeing two
>> signals (assuming dual polarity H/V interference) at that same signal level
>> and the two combined is essentially the same as seeing the extra 3db.
>> Hopefully someone who actually knows can confirm whether or not that's true.
>>
>> if that is the case, I think dual slant is mostly only going to help with
>> multipath issues.
>>
>> On Wed, Mar 25, 2015 at 2:36 PM, Jeremy <[email protected]> wrote:
>>
>>> Well if I can gain 3db by turning 45/45 I'm all over that.
>>>
>>> On Wed, Mar 25, 2015 at 1:32 PM, Josh Luthman <
>>> [email protected]> wrote:
>>>
>>>> That's what everyone keeps saying =)
>>>>
>>>>
>>>> Josh Luthman
>>>> Office: 937-552-2340
>>>> Direct: 937-552-2343
>>>> 1100 Wayne St
>>>> Suite 1337
>>>> Troy, OH 45373
>>>>
>>>> On Wed, Mar 25, 2015 at 3:30 PM, Jeremy <[email protected]> wrote:
>>>>
>>>>> 3db right?
>>>>>
>>>>> On Wed, Mar 25, 2015 at 12:54 PM, Josh Luthman <
>>>>> [email protected]> wrote:
>>>>>
>>>>>> Rejection from other V/H radios.
>>>>>>
>>>>>>
>>>>>> Josh Luthman
>>>>>> Office: 937-552-2340
>>>>>> Direct: 937-552-2343
>>>>>> 1100 Wayne St
>>>>>> Suite 1337
>>>>>> Troy, OH 45373
>>>>>>
>>>>>> On Wed, Mar 25, 2015 at 2:53 PM, Ken Hohhof <[email protected]> wrote:
>>>>>>
>>>>>>> Anybody know what you give up by using V/H instead of dual slant
>>>>>>> with the AF5X?
>>>>>>>
>>>>>>> If the path has clear LOS and no multipath, I can't see why it would
>>>>>>> care or even be able to tell the difference.
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
>
>

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