Antenna for cordless phone
in [Design]
|
From: tm on 18 May 2010 20:06 The information "mpm" posted below is very correct, and in addition, it is worth noting that the FCC Enforcement Branch is entirely self funded. Tom "mpm" <mpmillard(a)aol.com> wrote in message news:f1806f3a-b092-4b9e-899d-7d514bbe189b(a)d12g2000vbr.googlegroups.com... > >Here in the US, it's "antenna" and "antennas". > >You'll find antennae on bugs and cockroaches. :) > > >Sorry, that's just a pet peeve. Telecom attorneys make the same > >mistake all the time! > > >Also, if in the US, FCC rules prohibit you from monkeying around with > >the antennas. > >Legally speaking, if in the US, you'll just have to live with it, or > >select an alternate technology / device. > > >-mpm- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text - Not obsessed. Just alerting the OP to federal law. :) If he chooses to break the law, those same laws provide for fines and arrest of the equipment (in rem arrest), and the FCC can also refer cases to the Justice Department for further prosecution. Monetary fines for something like this can range from a few thousand, to ten thousand dollars or more. See generally, FCC Rules 47CFR1.80 Those are the facts. Now, does the FCC catch a lot of folks hacking illegal antennas into their cordless phones? No. But you might be suprised at just how many violations are issued each year by the FCC's Enforcement Division. I have personally been on a couple equipment witch hunts (for interference) with the Miami and Denver field agents. The outcomes are rarely pretty in the cases which I'm typically involved in (the high profile ones). The average homeowner can expect a Citation (no money fine) for a first offense, but things can get nasty if they're uncorporative, etc..., or if the Agent (for whatever reason) feels justified in pursing the matter more aggressively. Plus, in my former career (a post you may have missed?) it should be painfully obvious why I recoil when I hear that people want to hack into their consumer electonics. You would not believe the headaches this can cause for licensed radio services!! But to your facts, For most unlicened devices like cordless phone and the like, they'll be registered under Part-15 rules. (47CFR15) Those rules will provide field strength limits (not transmitter power output restrictions). Therefore, antennas matter greatly! The allowable field varies by frequency, according to a chart in FCC Rules part 15.209 Before leaving this topic, you should be aware that just because you might feel Part-15 devices are low power, that DOES NOT mean they are incapable of causing harmful interference. Far from it. For example, did you know a typical CDMA or GSM cell phone (operating at its lower power output of ~ -50dBm) actually radiates LESS power than the maximum permissible under Part-15 Rules for unlicensed devices? In other words, something that's unlicensed (and lower power) actually puts out MORE power than your cell phone -- which is very much a licensed service (FCC Part 22, 24 or 27) And note also that Part-15 Low Power does not restrict operation in the Cellular / PCS bands. Think about that next time you drop a call. It may just be your neighbor hacked in an antenna on his cordless phone (or garage door opener, or blender, or TV or god knows what!) This is one of hundreds of examples I could give to you. So yeah, you might say I'm "obsessed" -- but I am absolutely correct, and this history books are filled with examples of horrendous interference cause by well-intentioned folks just like the OP.!! Specific to this exact situation, here is the precise rule the OP would be violating: Sec. 15.203 Antenna requirement. An intentional radiator shall be designed to ensure that no antenna other than that furnished by the responsible party shall be used with the device. The use of a permanently attached antenna or of an antenna that uses a unique coupling to the intentional radiator shall be considered sufficient to comply with the provisions of this section. The manufacturer may design the unit so that a broken antenna can be replaced by the user, but the use of a standard antenna jack or electrical connector is prohibited. This requirement does not apply to carrier current devices or to devices operated under the provisions of Sec. 15.211, Sec. 15.213, Sec. 15.217, Sec. 15.219, or Sec. 15.221. Further, this requirement does not apply to intentional radiators that must be professionally installed, such as perimeter protection systems and some field disturbance sensors, or to other intentional radiators which, in accordance with Sec. 15.31(d), must be measured at the installation site. However, the installer shall be responsible for ensuring that the proper antenna is employed so that the limits in this part are not exceeded.
From: Joerg on 18 May 2010 20:47 D Yuniskis wrote: > Hi Joerg, > > Joerg wrote: >>> I'll drag out a GPS and get some actual measurements, >>> if necessary. I've not done an exhaustive survey >>> of where things work/don't work. Though I have found >>> the upper left corner to be a problem area as I am >>> often passing through there when I lose signal. >>> >>> The antenna that I was *questioning* will (physically) >>> mate to a Linksys wireless router (though not intended >>> to do so, "just coincidence" -- sorry, I don't deal with >>> RF stuff so i can't tell you what sort of connectors >>> they are -- I don't think they will mate with the >>> base unit on the phone :<) >> >> Cordless phone on a Linksys router? >> >> <scratching head> > > No, I was trying to describe the type of connector on the > antenna that I am "questioning" -- without KNOWING the > proper names for the various RF plumbing! :> > > I figured most folks have seen a linksys router (with > removable antennae) so could relate to that example. > > The phone's base unit is something like a "reverse TNC" > (??) so I can't mate the antenna to the base unit > "as is". There's usually clandestine adapters for that. Of course the FCC bristles at those ... -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: mpm on 18 May 2010 21:15 On May 18, 6:09 pm, D Yuniskis <not.going.to...(a)seen.com> wrote: > Hi Joerg, > > > > > > Joerg wrote: > >> I'll drag out a GPS and get some actual measurements, > >> if necessary. I've not done an exhaustive survey > >> of where things work/don't work. Though I have found > >> the upper left corner to be a problem area as I am > >> often passing through there when I lose signal. > > >> The antenna that I was *questioning* will (physically) > >> mate to a Linksys wireless router (though not intended > >> to do so, "just coincidence" -- sorry, I don't deal with > >> RF stuff so i can't tell you what sort of connectors > >> they are -- I don't think they will mate with the > >> base unit on the phone :<) > > > Cordless phone on a Linksys router? > > > <scratching head> > > No, I was trying to describe the type of connector on the > antenna that I am "questioning" -- without KNOWING the > proper names for the various RF plumbing! :> > > I figured most folks have seen a linksys router (with > removable antennae) so could relate to that example. > > The phone's base unit is something like a "reverse TNC" > (??) so I can't mate the antenna to the base unit > "as is".- Hide quoted text - > > - Show quoted text - You can probably get a reverse TNC from Pasternack. (?)
From: Joe on 18 May 2010 21:16 On Tue, 18 May 2010 16:09:28 -0700, D Yuniskis wrote: > Joerg wrote: .... >>> The antenna that I was *questioning* will (physically) mate to a >>> Linksys wireless router (though not intended to do so, "just >>> coincidence" -- sorry, I don't deal with RF stuff [...] >> >> Cordless phone on a Linksys router? >> >> <scratching head> > > No, I was trying to describe the type of connector on the antenna that I > am "questioning" -- without KNOWING the proper names for the various RF > plumbing! :> > > I figured most folks have seen a linksys router (with removable > antennae) so could relate to that example. > > The phone's base unit is something like a "reverse TNC" (??) so I can't > mate the antenna to the base unit "as is". RP-SMA is common on wireless routers. A few use standard SMA instead of the reverse-polarity version. Connector thread = 1/4"-36. See the SMA section of <http://www.wa1mba.org/rfconn.htm> and the "Matable Connectors" table at the end of that page. <http://en.wikipedia.org/wiki/SMA_connector> says, "RP-SMA connectors are widely used by Wi-Fi equipment manufacturers to comply with [FCC regulations] which are designed to make it difficult for consumers to connect antennas with gain and thereby breach compliance." <http://www.sparkfun.com/commerce/product_info.php?products_id=592> lists an SMA to RP-SMA adapter and a multiband antenna, which in turn links to various-band antennae with SMA or RP-SMA connectors.
From: mpm on 18 May 2010 21:31
On May 18, 8:15 pm, mpm <mpmill...(a)aol.com> wrote: > On May 18, 6:09 pm, D Yuniskis <not.going.to...(a)seen.com> wrote: > > > > > > > Hi Joerg, > > > Joerg wrote: > > >> I'll drag out a GPS and get some actual measurements, > > >> if necessary. I've not done an exhaustive survey > > >> of where things work/don't work. Though I have found > > >> the upper left corner to be a problem area as I am > > >> often passing through there when I lose signal. > > > >> The antenna that I was *questioning* will (physically) > > >> mate to a Linksys wireless router (though not intended > > >> to do so, "just coincidence" -- sorry, I don't deal with > > >> RF stuff so i can't tell you what sort of connectors > > >> they are -- I don't think they will mate with the > > >> base unit on the phone :<) > > > > Cordless phone on a Linksys router? > > > > <scratching head> > > > No, I was trying to describe the type of connector on the > > antenna that I am "questioning" -- without KNOWING the > > proper names for the various RF plumbing! :> > > > I figured most folks have seen a linksys router (with > > removable antennae) so could relate to that example. > > > The phone's base unit is something like a "reverse TNC" > > (??) so I can't mate the antenna to the base unit > > "as is".- Hide quoted text - > > > - Show quoted text - > > You can probably get a reverse TNC from Pasternack. (?)- Hide quoted text - > > - Show quoted text - Here's the link: http://www.pasternack.com/category-Connector-Wizard-5.html |