Re: [AFMUG] [*] corrective optics

2019-03-28 Thread Chuck McCown 
How about some photos.

Sent from my iPhone

> On Mar 28, 2019, at 6:58 AM, Ken Hohhof  wrote:
> 
> If you ever do the experiment again, it would be interesting to rotate the 
> antenna to see if there’s some kind of sidelobe pointed toward the ground or 
> something.  Obviously you can’t install it rotated or upside down (unless you 
> really trust that cable gland to seal against rain), but it would be 
> interesting to see the results.  Like you said, maybe some component in the 
> feed horn is blocking the RF.
>  
> Cambium is in a better position to investigate this, it’s disappointing if 
> they aren’t taking it seriously.
>  
>  
> From: AF  On Behalf Of Mark Radabaugh
> Sent: Thursday, March 28, 2019 6:19 AM
> To: AnimalFarm Microwave Users Group 
> Subject: Re: [AFMUG] [*] corrective optics
>  
>  
> 
> 
> On Mar 27, 2019, at 10:11 PM, Ken Hohhof  wrote:
>  
> In another thread, Mark Radabaugh posted:
>  
> “For your next product….   Corrective optics for 450B high gain CPE!”
>  
> Mark, I’m not sure if you were serious, I suspect yes.
>  
>  
> Yes - but I’m not sure what is possible with the design.
> 
> 
>  
> I know it’s frustrating that the antenna gain is lower than the old reflector 
> dish, Cambium dropped the number on the spec sheet to 24 dBi, but I think 
> even that is optimistic, I think it’s about 2 dB less than the old combo 
> which was supposed to be 25 dBi.  Lower antenna gain is going the wrong way!  
> I don’t care if it does have higher xmt power, that does nothing for the 
> downstream direction.
>  
>  
> Changing the spec sheet to match what they ended up with was a pretty big cop 
> out when the product failed to meet design expectations.   
> 
> 
>  
> In calling for corrective optics, do you have any info or even a gut feel for 
> whether the problem is in the feed or the dish?  Is it as simple as the dish 
> is just too small?
>  
>  
> I suspect that they managed to block part of the antenna feed horn with other 
> components.  
>  
> 
> 
>  
> Also, is it just the gain is low, or does the 450b hi gain have other issues? 
>  Like poor F/B or sidelobe performance or something?
>  
> It seems like if the 450b high gain is far away from other surfaces it works 
> mostly to spec but when mounted in the typical locations near rooftops it 
> seems like it either picks up more destructive multipath interference than 
> previous designs or the antenna pattern distorts badly.  For a long time I 
> thought they didn’t manage to get the feedhorn in the focus of the dish but 
> Cambium assures me that it’s right.   We are seeing decent performance under 
> 5 miles but it seems to fall apart much quicker over 5 miles than would be 
> expected.
>  
> We set up a test with the bucket truck and drove it out and measured every 
> mile to 10 and it came back fine - but that was 50’ in the air with nothing 
> around.   Yet swapping out standard 450 SM’s with beehive or KP dishes with 
> 450B’s at >5 miles routinely fails with poor signal.   The difference is 
> often far more than the 2dB the spec sheets would indicate.   Sometimes it 
> works if the antenna is well away from all other surfaces like on a tower but 
> for the majority of installs the swap fails.   Why were we doing that anyway? 
>  We wanted to start using 5.1/5.2.
> 
> 
>  
> I know the 450b mid-gain is frustrating because apparently Cambium doesn’t 
> think a tight vertical pattern is important.  I keep wondering if a top and 
> bottom flap like on the old 2.4 Stingers would correct that.
>  
> Cambium seems to be sharing antenna designs between ePMP and 450, so the same 
> issues probably exist in the corresponding ePMP products.
> -- 
> AF mailing list
> AF@af.afmug.com
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>  
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Re: [AFMUG] [*] corrective optics

2019-03-28 Thread Ken Hohhof 
If you ever do the experiment again, it would be interesting to rotate the 
antenna to see if there’s some kind of sidelobe pointed toward the ground or 
something.  Obviously you can’t install it rotated or upside down (unless you 
really trust that cable gland to seal against rain), but it would be 
interesting to see the results.  Like you said, maybe some component in the 
feed horn is blocking the RF.

 

Cambium is in a better position to investigate this, it’s disappointing if they 
aren’t taking it seriously.

 

 

From: AF  On Behalf Of Mark Radabaugh
Sent: Thursday, March 28, 2019 6:19 AM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] [*] corrective optics

 

 





On Mar 27, 2019, at 10:11 PM, Ken Hohhof mailto:af...@kwisp.com> > wrote:

 

In another thread, Mark Radabaugh posted:

 

“For your next product….   Corrective optics for 450B high gain CPE!”

 

Mark, I’m not sure if you were serious, I suspect yes.

 

 

Yes - but I’m not sure what is possible with the design.





 

I know it’s frustrating that the antenna gain is lower than the old reflector 
dish, Cambium dropped the number on the spec sheet to 24 dBi, but I think even 
that is optimistic, I think it’s about 2 dB less than the old combo which was 
supposed to be 25 dBi.  Lower antenna gain is going the wrong way!  I don’t 
care if it does have higher xmt power, that does nothing for the downstream 
direction.

 

 

Changing the spec sheet to match what they ended up with was a pretty big cop 
out when the product failed to meet design expectations.   





 

In calling for corrective optics, do you have any info or even a gut feel for 
whether the problem is in the feed or the dish?  Is it as simple as the dish is 
just too small?

 

 

I suspect that they managed to block part of the antenna feed horn with other 
components.  

 





 

Also, is it just the gain is low, or does the 450b hi gain have other issues?  
Like poor F/B or sidelobe performance or something?

 

It seems like if the 450b high gain is far away from other surfaces it works 
mostly to spec but when mounted in the typical locations near rooftops it seems 
like it either picks up more destructive multipath interference than previous 
designs or the antenna pattern distorts badly.  For a long time I thought they 
didn’t manage to get the feedhorn in the focus of the dish but Cambium assures 
me that it’s right.   We are seeing decent performance under 5 miles but it 
seems to fall apart much quicker over 5 miles than would be expected.

 

We set up a test with the bucket truck and drove it out and measured every mile 
to 10 and it came back fine - but that was 50’ in the air with nothing around.  
 Yet swapping out standard 450 SM’s with beehive or KP dishes with 450B’s at >5 
miles routinely fails with poor signal.   The difference is often far more than 
the 2dB the spec sheets would indicate.   Sometimes it works if the antenna is 
well away from all other surfaces like on a tower but for the majority of 
installs the swap fails.   Why were we doing that anyway?  We wanted to start 
using 5.1/5.2.





 

I know the 450b mid-gain is frustrating because apparently Cambium doesn’t 
think a tight vertical pattern is important.  I keep wondering if a top and 
bottom flap like on the old 2.4 Stingers would correct that.

 

Cambium seems to be sharing antenna designs between ePMP and 450, so the same 
issues probably exist in the corresponding ePMP products.

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 <mailto:AF@af.afmug.com> AF@af.afmug.com
 <http://af.afmug.com/mailman/listinfo/af_af.afmug.com> 
http://af.afmug.com/mailman/listinfo/af_af.afmug.com

 

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Re: [AFMUG] corrective optics

2019-03-28 Thread Ken Hohhof 
That seems like a bad idea.

 

From: AF  On Behalf Of Ryan Ray
Sent: Wednesday, March 27, 2019 10:09 PM
To: AnimalFarm Microwave Users Group 
Subject: Re: [AFMUG] corrective optics

 

KPP seems to have a reflector for the 450b mid gain. I'd be interested to see 
what the performance is like on that. No spec numbers, no more info than that 
facebook post. I can't even find it on the website.

 

https://www.facebook.com/plugins/post.php?href=https%3A%2F%2Fwww.facebook.com%2Fkpperformanceantennas%2Fposts%2F535221240337947

 

 

 

On Wed, Mar 27, 2019 at 7:12 PM Ken Hohhof mailto:af...@kwisp.com> > wrote:

In another thread, Mark Radabaugh posted:

 

“For your next product….   Corrective optics for 450B high gain CPE!”

 

Mark, I’m not sure if you were serious, I suspect yes.

 

I know it’s frustrating that the antenna gain is lower than the old reflector 
dish, Cambium dropped the number on the spec sheet to 24 dBi, but I think even 
that is optimistic, I think it’s about 2 dB less than the old combo which was 
supposed to be 25 dBi.  Lower antenna gain is going the wrong way!  I don’t 
care if it does have higher xmt power, that does nothing for the downstream 
direction.

 

In calling for corrective optics, do you have any info or even a gut feel for 
whether the problem is in the feed or the dish?  Is it as simple as the dish is 
just too small?

 

Also, is it just the gain is low, or does the 450b hi gain have other issues?  
Like poor F/B or sidelobe performance or something?

 

I know the 450b mid-gain is frustrating because apparently Cambium doesn’t 
think a tight vertical pattern is important.  I keep wondering if a top and 
bottom flap like on the old 2.4 Stingers would correct that.

 

Cambium seems to be sharing antenna designs between ePMP and 450, so the same 
issues probably exist in the corresponding ePMP products.

-- 
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http://af.afmug.com/mailman/listinfo/af_af.afmug.com

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Re: [AFMUG] [*] corrective optics

2019-03-28 Thread Mark Radabaugh 


> On Mar 27, 2019, at 10:11 PM, Ken Hohhof  wrote:
> 
> In another thread, Mark Radabaugh posted:
>  
> “For your next product….   Corrective optics for 450B high gain CPE!”
>  
> Mark, I’m not sure if you were serious, I suspect yes.


Yes - but I’m not sure what is possible with the design.

>  
> I know it’s frustrating that the antenna gain is lower than the old reflector 
> dish, Cambium dropped the number on the spec sheet to 24 dBi, but I think 
> even that is optimistic, I think it’s about 2 dB less than the old combo 
> which was supposed to be 25 dBi.  Lower antenna gain is going the wrong way!  
> I don’t care if it does have higher xmt power, that does nothing for the 
> downstream direction.


Changing the spec sheet to match what they ended up with was a pretty big cop 
out when the product failed to meet design expectations.   

>  
> In calling for corrective optics, do you have any info or even a gut feel for 
> whether the problem is in the feed or the dish?  Is it as simple as the dish 
> is just too small?


I suspect that they managed to block part of the antenna feed horn with other 
components.  


>  
> Also, is it just the gain is low, or does the 450b hi gain have other issues? 
>  Like poor F/B or sidelobe performance or something?

It seems like if the 450b high gain is far away from other surfaces it works 
mostly to spec but when mounted in the typical locations near rooftops it seems 
like it either picks up more destructive multipath interference than previous 
designs or the antenna pattern distorts badly.  For a long time I thought they 
didn’t manage to get the feedhorn in the focus of the dish but Cambium assures 
me that it’s right.   We are seeing decent performance under 5 miles but it 
seems to fall apart much quicker over 5 miles than would be expected.

We set up a test with the bucket truck and drove it out and measured every mile 
to 10 and it came back fine - but that was 50’ in the air with nothing around.  
 Yet swapping out standard 450 SM’s with beehive or KP dishes with 450B’s at >5 
miles routinely fails with poor signal.   The difference is often far more than 
the 2dB the spec sheets would indicate.   Sometimes it works if the antenna is 
well away from all other surfaces like on a tower but for the majority of 
installs the swap fails.   Why were we doing that anyway?  We wanted to start 
using 5.1/5.2.

>  
> I know the 450b mid-gain is frustrating because apparently Cambium doesn’t 
> think a tight vertical pattern is important.  I keep wondering if a top and 
> bottom flap like on the old 2.4 Stingers would correct that.
>  
> Cambium seems to be sharing antenna designs between ePMP and 450, so the same 
> issues probably exist in the corresponding ePMP products.
> -- 
> AF mailing list
> AF@af.afmug.com 
> http://af.afmug.com/mailman/listinfo/af_af.afmug.com 
> 
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Re: [AFMUG] corrective optics

2019-03-28 Thread Chuck McCown 
I love an antenna project.  My problem is that I don’t use the product so I 
don’t have any hardware to test and play with.

Sent from my iPhone

> On Mar 27, 2019, at 8:11 PM, Ken Hohhof  wrote:
> 
> In another thread, Mark Radabaugh posted:
>  
> “For your next product….   Corrective optics for 450B high gain CPE!”
>  
> Mark, I’m not sure if you were serious, I suspect yes.
>  
> I know it’s frustrating that the antenna gain is lower than the old reflector 
> dish, Cambium dropped the number on the spec sheet to 24 dBi, but I think 
> even that is optimistic, I think it’s about 2 dB less than the old combo 
> which was supposed to be 25 dBi.  Lower antenna gain is going the wrong way!  
> I don’t care if it does have higher xmt power, that does nothing for the 
> downstream direction.
>  
> In calling for corrective optics, do you have any info or even a gut feel for 
> whether the problem is in the feed or the dish?  Is it as simple as the dish 
> is just too small?
>  
> Also, is it just the gain is low, or does the 450b hi gain have other issues? 
>  Like poor F/B or sidelobe performance or something?
>  
> I know the 450b mid-gain is frustrating because apparently Cambium doesn’t 
> think a tight vertical pattern is important.  I keep wondering if a top and 
> bottom flap like on the old 2.4 Stingers would correct that.
>  
> Cambium seems to be sharing antenna designs between ePMP and 450, so the same 
> issues probably exist in the corresponding ePMP products.
> -- 
> AF mailing list
> AF@af.afmug.com
> http://af.afmug.com/mailman/listinfo/af_af.afmug.com
-- 
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Re: [AFMUG] corrective optics

2019-03-27 Thread Ryan Ray 
KPP seems to have a reflector for the 450b mid gain. I'd be interested to
see what the performance is like on that. No spec numbers, no more info
than that facebook post. I can't even find it on the website.

https://www.facebook.com/plugins/post.php?href=https%3A%2F%2Fwww.facebook.com%2Fkpperformanceantennas%2Fposts%2F535221240337947



On Wed, Mar 27, 2019 at 7:12 PM Ken Hohhof  wrote:

> In another thread, Mark Radabaugh posted:
>
>
>
> “For your next product….   Corrective optics for 450B high gain CPE!”
>
>
>
> Mark, I’m not sure if you were serious, I suspect yes.
>
>
>
> I know it’s frustrating that the antenna gain is lower than the old
> reflector dish, Cambium dropped the number on the spec sheet to 24 dBi, but
> I think even that is optimistic, I think it’s about 2 dB less than the old
> combo which was supposed to be 25 dBi.  Lower antenna gain is going the
> wrong way!  I don’t care if it does have higher xmt power, that does
> nothing for the downstream direction.
>
>
>
> In calling for corrective optics, do you have any info or even a gut feel
> for whether the problem is in the feed or the dish?  Is it as simple as the
> dish is just too small?
>
>
>
> Also, is it just the gain is low, or does the 450b hi gain have other
> issues?  Like poor F/B or sidelobe performance or something?
>
>
>
> I know the 450b mid-gain is frustrating because apparently Cambium doesn’t
> think a tight vertical pattern is important.  I keep wondering if a top and
> bottom flap like on the old 2.4 Stingers would correct that.
>
>
>
> Cambium seems to be sharing antenna designs between ePMP and 450, so the
> same issues probably exist in the corresponding ePMP products.
> --
> AF mailing list
> AF@af.afmug.com
> http://af.afmug.com/mailman/listinfo/af_af.afmug.com
>
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[AFMUG] corrective optics

2019-03-27 Thread Ken Hohhof 
In another thread, Mark Radabaugh posted:

 

"For your next product..   Corrective optics for 450B high gain CPE!"

 

Mark, I'm not sure if you were serious, I suspect yes.

 

I know it's frustrating that the antenna gain is lower than the old
reflector dish, Cambium dropped the number on the spec sheet to 24 dBi, but
I think even that is optimistic, I think it's about 2 dB less than the old
combo which was supposed to be 25 dBi.  Lower antenna gain is going the
wrong way!  I don't care if it does have higher xmt power, that does nothing
for the downstream direction.

 

In calling for corrective optics, do you have any info or even a gut feel
for whether the problem is in the feed or the dish?  Is it as simple as the
dish is just too small?

 

Also, is it just the gain is low, or does the 450b hi gain have other
issues?  Like poor F/B or sidelobe performance or something?

 

I know the 450b mid-gain is frustrating because apparently Cambium doesn't
think a tight vertical pattern is important.  I keep wondering if a top and
bottom flap like on the old 2.4 Stingers would correct that.

 

Cambium seems to be sharing antenna designs between ePMP and 450, so the
same issues probably exist in the corresponding ePMP products.

-- 
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