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SisKnil
@comcast.net

SisKnil

Anon

2 more illegal CPE's from Demarc

Do the math

28dB radio output using the point to point 3:1 rule allows only a 12dB antenna gain.

»www.demarctech.com/produ ··· -15a.htm

»www.demarctech.com/produ ··· -19a.htm

What's an approval? Approvals FCC Part15, Section 15,247
haywire4
join:2006-08-28
San Francisco, CA

haywire4

Member

Are you a self proclaimed community police service member?

kewlkeed
Grouch
Premium Member
join:2005-02-05
Knowlton, QC

kewlkeed to SisKnil

Premium Member

to SisKnil
*Hands out little kid's Sherrif Badges*
Hey maybe these will make us look cool too.

LLigetfa
join:2006-05-15
Fort Frances, ON

LLigetfa

Member

Lay off the jokes, guys. You may think it funny now but you won't be laughing when your neighbor cranks up a pair of these and knocks out your POP.
steve_NVa
join:2005-02-13
Leesburg, VA

1 edit

steve_NVa to SisKnil

Member

to SisKnil
How can this be justified? - I'd see the logic being something like this:

All of the parts are individually certified or tested for FCC compliance, so the assembly is OK as long as it is used in a legal manner. The end user would be responsible to not overpower the radio, i.e. reduce the RF TX gain to 26 dB to allow the 19 dB antenna, if you also allow for a 1 db connector loss.

Just playing devil's advocate. Don't beat me up for this opinion

I think this logic stretches a little thin when you turn around and sell the device to others.

Thoughts from others? If this is OK, I'd love to assemble old spare parts into assembled units and sell them on ebay to people in areas I don't serve

superdog
I Need A Drink
MVM
join:2001-07-13
Lebanon, PA

superdog to LLigetfa

MVM

to LLigetfa
said by LLigetfa:

Lay off the jokes, guys. You may think it funny now but you won't be laughing when your neighbor cranks up a pair of these and knocks out your POP.
I agree. There are plenty of idiots that have the "Tim the tool man" approach, and more power is better attitude. That 15dBi unit cranked all the way up could spew a lot of RF if used incorrectly.

aSic
application specific
Premium Member
join:2001-05-17
Wakulla, FL

aSic to SisKnil

Premium Member

to SisKnil
Following that logic, we should outlaw all cars that can exceed the speed limit too.

Just because you've got a car that can do 140mph doesnt mean you should do it, or its illegal for the company to produce/sell. Its up to the user to be responsible enough to know how to properly use the product, be it cars, or radios.
LLigetfa
join:2006-05-15
Fort Frances, ON

LLigetfa

Member

said by aSic:

Following that logic, we should outlaw all cars that can exceed the speed limit too.
Well... the FCC makes the rules (IC in my case), not the Motor Vehicle branch.

Nobody wants a four-lane superhighway running past the front of their house but they all want to drive faster than they should down their quaint winding country lane. Hence they do drive too fast and put others at risk.

Nobody wants to cut down their trees and/or put up a tower to get a good solid link and no WISP wants to turn away a customer so they turn up the radio and blast through.

There is a mini-POP on my neighbor's utility pole, not even at the top of it but below the telephone line. Trees are higher than the pole which is more than 500 feet away and through trees on a rainy day, I see it at -74 with my built-in WIFI card on my laptop. Some days it's stronger than my WIFI in my house not 30 feet away. Only three out of five of my neighbors actually have LOS.

Now, I'm sure this is all put together with legally acquired gear and I cannot say what the actual EIRP is but I do wonder how well self-policing does work.

I think the sinner cries the loudest when sinned against.
mrbueno
join:2002-08-03
US

mrbueno to SisKnil

Member

to SisKnil
I do loathe the way this thread started. A more reasonable way to do this is:

Hey Caleb, how is it that your company feels this is a legal setup?

dongato17
join:2000-07-28
Atlanta, GA

dongato17

Member

said by mrbueno:

Hey Caleb, how is it that your company feels this is a legal setup?
I'm sure Caleb has an opinion but he works for Deliberant, not Demarc.
LLigetfa
join:2006-05-15
Fort Frances, ON

LLigetfa

Member

said by dongato17:

I'm sure Caleb has an opinion but he works for Deliberant, not Demarc.
Now Caleb is not as common a name as Tom, Dick, or Harry, but how can you be sure someone called Caleb doesn't work at Demarc?

Google gives me around 8,950,000 hits for caleb.

dongato17
join:2000-07-28
Atlanta, GA

dongato17

Member

Touche.

I suppose Caleb was in the bible too... So he's been around a while.
MrMcDuck
join:2006-11-27
USA

MrMcDuck to SisKnil

Member

to SisKnil
How is this any differant than what sellers like HGA sell?

Or am I way off base here?

SisKnil
@comcast.net

SisKnil to aSic

Anon

to aSic
aSic

You will need to gain some education on MAX EIRP limits and FCC compliancy. You cannot compare this to a car.

1. Selling an all in one CPE that has the ability for the end user to exceed MAX EIRP limits is illegal.

2. Using the 3:1 rule you cannot exceed a 12dB antenna gain at 28dB of radio output.

3. Advertising that the CPE has some sort of FCC compliancy is just flat deceiving the public.
steve_NVa
join:2005-02-13
Leesburg, VA

steve_NVa to mrbueno

Member

to mrbueno
I tried to make the shift to a discussion of the concern rather than an accusation. Sorry that everyone ignored it.

I believe I posted a strawman argument that could be used to defend product in question. From previous discussion threads I don't believe the argument is persuasive. I was hoping for someone to step up with a credible defense of the argument.

Steve
steve_NVa

steve_NVa to SisKnil

Member

to SisKnil
SisKnil,
Aren't there radios on the market that "can" exceed FCC limits, but require professional installation when deployed to ensure they don't?
40883644 (banned)
join:2003-06-05
Parker, CO

40883644 (banned) to MrMcDuck

Member

to MrMcDuck
MrMcDuck

I don't know that I would say you are way off base, just off base. From what I have read and I haven't spent much time doing so, It appears Demarc is selling all-in-one CPE's as linked to above that have a radio output capability of 28dB. That coupled to a 15dB antenna or a 19dB antenna is above the maximum legal EIRP allowed by the FCC. We do not sell an all in one CPE where the end user can exceed the legal maximum EIRP.

Rich
www.highgainantennas.com

dongato17
join:2000-07-28
Atlanta, GA

dongato17

Member

As Rich said, professional installation is for radios with a connector where you can add an antenna. As far as I know there are not any "all-in-one" CPE's that have passed FCC testing with higher than allowed limits. Of course there may be one out there an I just haven't come across it.

-Hal
cmaenginsb1
Premium Member
join:2001-03-19
Palmdale, CA

cmaenginsb1 to SisKnil

Premium Member

to SisKnil
Steve as Hal states the "professional" clause still requires the assembled system to follow the same limits as any other 2.4 radio.

It's very easy for an end user to take individually certified components and make an illegal overpowered system, but as sysknil notes you cannot take that system, make it into an all in one radio, certify and sell it.

superdog
I Need A Drink
MVM
join:2001-07-13
Lebanon, PA

superdog

MVM

said by cmaenginsb1:

Steve as Hal states the "professional" clause still requires the assembled system to follow the same limits as any other 2.4 radio.

It could also be said that from a manufacturing standpoint, it may be easier for the CO in question to standardize on one type of board/radio and then use that product in every type of CPE option they make?. That would allow that OEM to keep manufacturing costs down while offering the end user a bunch of different options. I guess the problem with this line of thought is that it passes the burden of staying within the letter of the law onto the end user. While this may be OK in some circumstances, most of us are aware that quite a few buyers of this product either have no clue about the part 15 laws, OR, they simply choose to ignore them for whatever reason.

When you try and decide who should be responsible for following the law, you need to look at how other laws are enforced. For instance, the example of a car being able to travel at speeds well over the posted limits is a perfect example. Even the bottom line cheap cars can travel much faster than the national high speed limits of 65 to 70 mph. This fact alone places the burden of following the law itself onto the end user. The same logic applies when looking at guns and/or knives. Both of these devices have the ability to do harm to another person/s, but that fact alone does not stop their sale. The guns however do need to be registered to the person who bought them, so that if a crime is committed, it can be traced to an individual who originally purchased it, giving law enforcement someplace to start looking when something goes wrong.

As mentioned by cmaenginsb1 See Profile, the "professional" clause still requires the assembled system to follow the same limits as any other 2.4 radio, but here again, the radios that are sold with an N connector allow anyone to break the law by just adding an antenna that is either not certified or causes the unit to TX/RX at a power level above the rules of part-15.

All of this makes me wonder if requiring anyone who buys anything other than a consumer grade radio to have some sort of license or professional certification a good idea? While I know there have been arguments for and against it, I have been leaning more towards a license/product registration scheme every day. While it may seem like a burden or a hassle to some of you, SOMETHING has to happen in the near future, otherwise the spectrum we use every day will be gone in another year or two. Lets face it, every single one of us have come across some type of setup that blatantly disregards the rules, and whether it is done with intent or ignorance, it is there and causes us problems in one way or another.

You could say that by forcing all of the OEM's to only sell radios that are capped at max EIRP would be a better option than requiring a license to purchase and operate radios in this band, but all of us know that law breakers will just crack the case and do what they want anyway, so will that really stop the idiots?.

You could also say that just because one has a license does not mean that person will not break the law, but then at least they could be held accountable, and not be able to plead ignorance at the time of the violation.

Hmmm........If we only had an answer to this problem?
cmaenginsb1
Premium Member
join:2001-03-19
Palmdale, CA

cmaenginsb1

Premium Member

In this particular example, the radio should be capped in firmware to avoid an illegal power setting. I believe the FCC requires this of "complete" systems.
lutful
... of ideas
Premium Member
join:2005-06-16
Ottawa, ON

lutful

Premium Member

Demarctech owner Tony does not hang out in WISP forum. But if he did, I am sure he could point to dozens of such systems from other vendors.

However I interpret FCC/IC rules the same way as cmaenginsb. No radio assembly can provide end-users the ability to run at illegal power or frequency.

If such a system was ever submitted for certification, they will request a change in GUI and manual. Needless to say these are being sold uncertified.
mrbueno
join:2002-08-03
US

mrbueno to dongato17

Member

to dongato17
Holy crap I so didn't read.

My bad guys.

aSic
application specific
Premium Member
join:2001-05-17
Wakulla, FL

1 edit

aSic to cmaenginsb1

Premium Member

to cmaenginsb1
One must also remember that not everyone has to comply with part 15 rules. Some of us operate equipment under part 97. The term "illegal power setting" is subjective and should not be used. (I think subjective is the right word I'm looking for?)

These devices are no more illegal than the Ferarri outside the local nightclub. Depends on what rules (speed limit!) you fall under.

I fall in with superdog See Profile and believe that licensure and personal responsibility are the way to go.
steve_NVa
join:2005-02-13
Leesburg, VA

steve_NVa to cmaenginsb1

Member

to cmaenginsb1
Agree that selling of complete units that can exceed limits does not appear to be legal. Figure that I should balance my karma after beating up vendors on their forums when they imply homebuilt gear is legal because the CM9 is certified and a SBC is tested.

Good discussion.

Selling uncertified equipment would appear to be without consequence But selling legal gear does at least draw my business... I just bought a bunch from Hal instead of rolling my own.
cmaenginsb1
Premium Member
join:2001-03-19
Palmdale, CA

cmaenginsb1 to SisKnil

Premium Member

to SisKnil
Asic I understand your where you're coming from, that being said the aforementioned CPE specifically states it is certified under Part 15.247, however it doesn't appear that it could be based on EIRP restrictions for that Part (hopefully that isn't too subjective for you).

The term illegal power setting can be used when qualified as to what is illegal. As we are talking about power limits and requirements (the professional installer clause) that only exist in Part 15 it would be safe to assume we are not discussing part 97.

As to individual responsibility and licensing, while licensing would be interested, I've seen individual responsibility fly out the window in most competitive environments.

2 of the largest WISPs in the southern california area are operating illegally today, now and other than FCC involvement they will not change. One is using 36" dishes in the 5.1 Ghz (ie not even outdoor band, thanks Axcellera) and the other uses 1 watt amps on 12 db omnis in 2.4ghz and CBS wonders why they have problems using the full band for their mobile dishes.

The only way this stops is if the FCC steps in, period. In the case of the first WISP, if the manufacturer hadn't provided the WISP with the ability to hack the firmware to allow for power levels and operation outside of legal limits under the rules governing their use in this case (is that better?) they wouldn't be in use. In the case of the second WISP, this is a direct result of the ability for anyone to buy a 1 watt amp off the net and connect it to their Linksys.

Those who go for their HAM license are a different breed and self regulation can work in that environment but in the WISP world I don't see it flying.

Wireless Guru
@totalaccess.net

Wireless Guru to SisKnil

Anon

to SisKnil
Not all WISP's crank up the amps, and blow the flow. FCC management is needed when people purposely violate the rules, and is stepping on the RF of everyone else.

The controversy there is huge since the FCC also licenses HAM's and other groups use of the same bands it allows for unlicensed use. Every seen 100 watts of 2.4 ghz? It creates this kind of huge RF black hole....... nasty stuff....

I work and have played with allot of different gear and feel it is up to the WISP to manage the frequency and accept the FCC terms and conditions. Since most wireless guys are unlicensed , this limits things even more.

Instead of blasting, use frequencies that support NLOS or multi path mobile mesh. Works well at only 100 mW versus blasting through approach. The use of NLOS Mesh and Unlicensed Bands to support voice, video and data traffic with QOS instead of just wifi is another chapter in itself.

Your gear has ALLOT to do with what you can do and see with your wireless. Wireless vendors who build gear on shelf that can violate the rules, I feel is between them and the FCC. I am sure the RF is adjustable to meet any FCC or other country rule.

totalaccess
Premium Member
join:2002-10-04
Austin, TX

totalaccess to SisKnil

Premium Member

to SisKnil
Those new to wireless, louder is never better. I came from the sound industry into developing mesh now for 7 years right after 802.11b was finally agreed upon.

As a rule of thumb if your going to deploy wireless, follow the rules and those needing AMP's should seek licensed wireless installers since violating the FCC rules can be expensive and disruptive when they unplug or you unplug and comply, or they cut off.

Those engaged in VOIP I recommend joining WISPA.

tonymorella to SisKnil

Anon

to SisKnil
Guys
I have just read all the posts on this subject and wanted to respond:

- The main reason for creating this product was threefold, to create a product that would extend indoor self installs (indoor an 10dBi unit), create a better CPE that can use the max FCC allows power levels as well as help customer in 3rd world counties that do not have EIRP limits.

- The RWR products where designed to meet the needs for WISP using 2.4Ghz in all parts of the world, as such we tested by a third party (wll.com) for true temperature specification and FCC certification. The RWR was test from -45C to +85C at WLL and did continue working throughout the test; there was some error loss at the extremes so to be safe the unit is specified at -40C to +65C. FCC testing is complete we are just waiting for the final paper work which takes time to process.

- Full FCC certification will be on the website in a few weeks, the software in the integrated units has version to limit the power levels which can be found here which: »www.demarctech.com/techs ··· ads.html

- The 15dBi and 19dBi units follow the FCC 3 to 1 rule where for every dB off the radio one can add 3dB to the antenna. So for the 15dBi max power is 500mW (27dBm) which allows for a 15dBi antenna and for the 19dBi max power is 400mW (26dBm). Info on this can be found here: »www.demarctech.com/techs ··· ngs.html. We do make note of the allowed power levels on the web site spec.

- The 630mW is the max levels in DSSS or 802.11b mode, max power under OFDM is 250mW (which is very good!, most others are at 100mW check the specs!) Which we are under the FCC standard on any antenna type under 24dBm. We are seeing WISP starting to use 802.11g more and more and this RWR has been working very well for customers needed more speed on their networks.
- On a note about power, we have seen and tested MANY wifi radios over the years, many of them use the -/+3dBm to full extent. We keep ours -/+ 1dBm and test ever unit that we sell. Any that is out of spec are not sold at these power levels.
- In the recent months we have tested many radios that have a spec of 400mw or 500mw and while true take up the full band to make this happen or are way over spec and are really only 200mW!! So in other words they could never pass FCC certification at the spec levels.

-To give an example, one of our customers recently installed 75 units from another vender (at the time we did not offer the RWR units and these units where lower cost) to find out that there noise levels went up dramatically causing major issues on their network. They called us for help as most of their network is Demarc, and thought testing we found out that that the new CPES where the issues. When set to 400mW the channel was way out of the 20 MHz channel size and was talking up almost 80 MHz, and on the upper and lower channels was bleeding over to the licensed bands. After testing we found, with the customer, that the radio was in spec between 150-200mW. After lowering the power on all the radios the noise levels where at acceptable levels. The customer recently has informed me that many of the units have been replaced with RWR units and the network is running much better. My point to this example is there is no reason you cannot run at higher levels as long as you are using “clean” equipment and keep the RX and TX balanced at both the AP and CPE. You don’t want to run a CPE at 630mW if you are only a mile away from the AP, turn the power down to what is needed.

-As one person noted I do not monitor the forms much, as a limit of time so if anyone has questions please send them to tony@demarctech.com and I would be happy to help and have no issues with responses be post back to the forms.

Sincerely, Tony Morella
Demarc Technology Group, A Wireless Solution Provider
Office: 207-667-7583 Fax: 207-433-1008
»www.demarctech.com