Re: no direct line of sight wifi

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Jeff Liebermann

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Dec 7, 2020, 10:56:24 AM12/7/20
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On Mon, 7 Dec 2020 05:59:34 -0000 (UTC), JustMike
<Just...@nospaminvalid.org> wrote:

>Thanks in advance for any helpful answers, all info is in attachment.
>
>https://i.postimg.cc/pL9MgCY5/WIFIPOST12-7-20.png

Un-helpful questions:

1. I suggest you REDUCE your transmit power to something that is
about the same as the wireless router to which you're trying to
connect. At 1 watt and with a parabolic dish antenna, you are
probably well over FCC and international EIRP limits.

2. If you're posting a JPG or PNG of your question so that it's not
searchable by Google or the FCC, I want no part of whatever you're
trying to accomplish, which I suspect is connect to someone else's
internet connection without permission.

3. Your homemade dish with the long omni antenna is likely a bad
design. Low gain antennas are easy. High gain antennas are tricky
and need to be calculated and properly tested. Without proper RF test
equipment, you are unlikely to design and build anything that works. A
proper dish antenna uses a fairly low gain but directional feed
antenna to illuminate the entire dish antenna. Using a high gain
antenna as a feed will only illuminate a small part of a dish. In
transmit, such an omni feed antenna will spray RF in many directions
EXCEPT onto the dish, or will cover only a small part of the dish,
drastically reducing the transmit gain.

4. Your PNG image lacks any usable numbers from which to do a path
loss calculation. If you really want an answer or sanity check,
kindly supply:
- Equipment list at both ends
- Description and gain of the endpoint antennas
- Length and type of coaxial cable (if any) to the dish
- Distances involved
- Height of path (for Fresnel Zone calculations)
- Approximate size of the steel door reflector
- 2.4 or 5 GHz?

5. If you want to run your own calculations, grind the path loss
numbers for between the dish and the steel door, use the result to
calculate a 2nd path between the steel door and that wireless router.
I posted an example many years ago in this newsgroup, but can't seem
to find it. Here's an example of a single hop calculation:
<https://groups.google.com/g/alt.internet.wireless/c/QL5IT6CmlsA/m/QIFdwU56ficJ>
I'll try again later to find a better example.


--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

JustMike

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Dec 11, 2020, 4:22:21 AM12/11/20
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JustMike <Just...@nospaminvalid.org> wrote in
news:XnsAC8D723DEB0E6mi...@202.81.252.44:

> Jeff Liebermann <je...@cruzio.com> wrote in
> news:kfissfh4faudq884r...@4ax.com:
>
>> On Mon, 7 Dec 2020 05:59:34 -0000 (UTC), JustMike
>> <Just...@nospaminvalid.org> wrote:
>>
>>>Thanks in advance for any helpful answers, all info is in attachment.
>>>
>>>https://i.postimg.cc/pL9MgCY5/WIFIPOST12-7-20.png
>>
>> Un-helpful questions:
>>
>> 1. I suggest you REDUCE your transmit power to something that is
>> about the same as the wireless router to which you're trying to
>> connect. At 1 watt and with a parabolic dish antenna, you are
>> probably well over FCC and international EIRP limits.
>
> Well your ASSumption is that I am in the USA and subject to that
> (another) corrupt agency of the corrupt U.S. Gov. I am not. Yeah Trump!
>
>>
>> 2. If you're posting a JPG or PNG of your question so that it's not
>> searchable by Google or the FCC, I want no part of whatever you're
>> trying to accomplish, which I suspect is connect to someone else's
>> internet connection without permission.
>
> Better run and hide then.
>
>>
>> 3. Your homemade dish with the long omni antenna is likely a bad
>> design. Low gain antennas are easy. High gain antennas are tricky
>> and need to be calculated and properly tested. Without proper RF test
>> equipment, you are unlikely to design and build anything that works. A
>> proper dish antenna uses a fairly low gain but directional feed
>> antenna to illuminate the entire dish antenna. Using a high gain
>> antenna as a feed will only illuminate a small part of a dish. In
>> transmit, such an omni feed antenna will spray RF in many directions
>> EXCEPT onto the dish, or will cover only a small part of the dish,
>> drastically reducing the transmit gain.
>
> It's working well even bounced off a steel door at about a 45 degree
> angle. I THOUGHT it was my antennas but it turns out it's probably an
> ISP problem. They were out working on the lines but they are morons of
> the worst ISP here in this crap Country.
>
>>
>> 4. Your PNG image lacks any usable numbers from which to do a path
>> loss calculation. If you really want an answer or sanity check,
>> kindly supply:
>> - Equipment list at both ends
>> - Description and gain of the endpoint antennas
>> - Length and type of coaxial cable (if any) to the dish
>> - Distances involved
>> - Height of path (for Fresnel Zone calculations)
>> - Approximate size of the steel door reflector
>> - 2.4 or 5 GHz?
>
> You always make things too over complicated. As it turns out it
probably
> has nothing to do with my antennas and your overly complicated
> calculations. It's the crap ISP.
>
>>
>> 5. If you want to run your own calculations, grind the path loss
>> numbers for between the dish and the steel door, use the result to
>> calculate a 2nd path between the steel door and that wireless router.
>> I posted an example many years ago in this newsgroup, but can't seem
>> to find it. Here's an example of a single hop calculation:
>>
<https://groups.google.com/g/alt.internet.wireless/c/QL5IT6CmlsA/m/QIFd
>> wU56ficJ> I'll try again later to find a better example.
>
> Thanks for answering. Don't make so many ASSumptions cuz you know what
> that means. And don't accuse people you don't know of STEALING when you
> have no evidence of that. I am not stealing the connection is done with
> the main ISP account's owner.
>>
>>
>
For once the know it all has nothing to say....

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