DIY Cellular amplifier - AWS spectrum - Page 1
Forum section: electronics / beginners

author: EEBlackSheep
author_rank: Contributor
timestamp: September 29, 2012, 06:29:56 pm
content: I use T-Mobile for cell data and discovered that it uses the AWS spectrum (1700/2200 MHz). Wilson sells an amp kit for AWS, but is $400. Any schematics exists for AWS amplifiers that I can make myself?thanks

author: PA0PBZ
author_rank: Super Contributor
timestamp: September 29, 2012, 09:02:43 pm
content: For what purpose? Since it is 2-way you are not going to gain anything by amplifying the signal in just one direction...

author: EEBlackSheep
author_rank: Contributor
timestamp: September 30, 2012, 04:09:18 am
content: My other cell amplifier for GSM seem to work just fine for 3G/4G data.Anywhooo, back to the original topic: anyone know of an ASW amp circuit, google has not turned up anything.

author: vk6zgo
author_rank: Super Contributor
timestamp: September 30, 2012, 05:55:47 am
content: Probably illegal!

author: EEBlackSheep
author_rank: Contributor
timestamp: October 01, 2012, 03:55:08 am
content: Come on guys, cut me a little slack with the off-topic comments. You can buys these cell amps LEGALLY from Wilson.Please no peanut gallery comments - if anyone knows of an AWS amp schematic, it would be much appreciated.

author: ejeffrey
author_rank: Super Contributor
timestamp: October 01, 2012, 09:25:19 am
content: Whether you can buy an amplifier legally or not does not imply it is legal to use it in a specific way. i.e., transmitting on a licensed band by someone other than the licensee.In any case, you haven't really provided any details about what you want to, or even linked to the amplifier you think does what you want, so there isn't much to answer. Yes, you can make a microwave ampliifer, or you can buy an amplifier on a chip from minicircuits. Turning it into something useful is going to be difficult or impossible depending on what your goals are or how you want to use it.

author: EEBlackSheep
author_rank: Contributor
timestamp: October 01, 2012, 04:14:59 pm
content: The information I provded is more than adequate. Cell phone amplifiers are common enough, and I am looking for a circuit for one. One in the AWS band. You obviously dont know enough about it.So far all I have gotten from the responses is: (1) why bother it does not work. (2) Not legal (3) not enough info (which is incorrect).If you dont know the answer, then why even bother replying? Just like to hear your own voice? Man do I get tired of hearing this kind of crap. Me thinks this forum is for guys who like to spout off there useless opinions so they can feel good about themselves.Do you think your response is actually helpful?

author: ejeffrey
author_rank: Super Contributor
timestamp: October 01, 2012, 06:16:09 pm
content: I can't speak for anyone else, but I seriously do not know what you mean by a cell phone amplifier. Link to the product your are talking about, explain what you are talking about, or quit bitching. Do you literally mean an RF amplifier, or do you mean a repeater? How are you going to connect it? Does it need to be bidirectional or not? Is this actually for a phone, or for a special purpose fixed receiver for a "broadband over cellular" service?These things matter, and the fact that you can't even understand what you need to ask suggests a very low level of technical expertise. In which case, I can answer your question: No, it is not possible for you to DIY any sort of microwave circuit. Pay the $400 or give up.Finally, don't get defensive about people telling you what you are doing is probably illegal. Some of us like our cell phone data service. I don't really want to help some cowboy amateur to accidentally build a cell phone jammer.

author: h1386343
author_rank: Regular Contributor
timestamp: October 05, 2012, 02:47:08 am
content: Quote from: ejeffrey on October 01, 2012, 06:16:09 pmThe cell phone jammer is illegal in every country or not? where i can use it?

author: BlaineByrnside
author_rank: Newbie
timestamp: May 21, 2014, 02:02:59 am
content: As you know that the mobile phone signal jammer can cut off the signals of the mobile phones and soon make it impossible to make phone calls or send messages. In this way when you need the peaceful condition and want to stay in it, you can just use the best mobile phone jammer to help you achieve your goal. And now as the technology develops with high speed the advanced Military Jammer has come into the market and are well welcomed by the group of people who need the jammer product.spammer link deleted

author: ahnuts72
author_rank: Regular Contributor
timestamp: May 21, 2014, 03:23:51 am
content: He's not asking about a jammer or anything like that.What he is after anyone can buy its not illegal to own.The one i looked st had a antenna you could place on the roof of your house and the other part you place inside your house so you have better signal inside.Its like a small repeater for you cell phone.The commercial ones are rather pricey

author: richard.cs
author_rank: Super Contributor
timestamp: May 21, 2014, 09:36:19 am
content: Quote from: ahnuts72 on May 21, 2014, 03:23:51 amPassive repeaters like this do work (sort of) and have no legal issues. They're nothing more than a high gain (directionality, not power gain) antenna placed outside aimed at the cell tower and a low gain omnidirectional antenna inside. They have no amplification, they just provide a means to pass the signals through walls and to reduce the 1/r2loss. When poorly implemented you loose more signal in the coax than you would just going through the wall so they do nothing but they are quite DIY-able.

author: Fank1
author_rank: Regular Contributor
timestamp: May 22, 2014, 10:26:20 pm
content: I don't know of any schematics, BUT, DIY at 2 GHZ is something you probably don't even want to try without a ful rf lab.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: May 22, 2014, 11:53:38 pm
content: Quote from: vk6zgo on September 30, 2012, 05:55:47 amLike I said before a Godwin's law of this forum states that :"As an online discussion grows longer, the probability of someone saying it is illegal of not safe approaches 1".It appears that there are whole class of people who spend their entire life going over online forums providing no input besides comments like "It is prolly illegal" or "It is not safe".

author: Stonent
author_rank: Super Contributor
timestamp: May 23, 2014, 12:18:26 am
content: http://www.myfoxdfw.com/story/25405289/man-arrested-for-jamming-drivers-cell-phones-on-the-interstatehttp://tbo.com/news/business/fcc-seffner-man-was-using-cell-phone-jammer-20140429/

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: May 23, 2014, 12:51:54 am
content: Quote from: Stonent on May 23, 2014, 12:18:26 amAnd point is ...?You would assume people that participate in discussion on this electronics-related forum are pretty intelligent and generally know what they are doing. I hope they are intelligent otherwise I wouldn't be here :-) When I see comment like this I always think - "Does he think everyone here is an idiot?".Second people here are fromentire globe, majority is in fact from outside of US with different laws and regulations etc. Just saying "it is illegal" at best does not make ANY sense at all. Cell phone jammers for example installed in many of schools in India and Ukraine where they are legal. What is FCC? - some kind of institution in USA I guess?And also have to apologize because this whole discussion is as much an offtopic as original comment. Normally I would say nothing, but when almost every strictly technical discussion getting riddled with comments like "it is illegal" or "it is unsafe" it starts to get little bit annoying.

author: ve7xen
author_rank: Super Contributor
timestamp: May 23, 2014, 01:13:16 am
content: Quote from: Alexei.Polkhanov on May 23, 2014, 12:51:54 amYou would assume, but people ask stupid questions on this forum every day. OP's original question and subsequent follow up make it pretty clear they're not going to be aware of RF licensing regulations considering the apparent unawareness of anything to do with RF.If something is obviously likely to be illegal, why would you complain about pointing that out? Pointing out potential legal issues that may not be obvious to the OP may be just as important as pointing out technical issues. It's certainly not off-topic or out of line to mention such issues, as someone asking such a question is very likely to be unaware of them. I don't know why you have a problem with it, especially something as clear cut as this. RF spectrum is licensed pretty much everywhere in the world, and unlicensed transmitters are almost certainly illegal in any country where T-Mobile operates. If that were not the case and OP were aware of it, they could simply say "oh, I know, but I'm in country X where AWS is an ISM band" or whatever.

author: Stonent
author_rank: Super Contributor
timestamp: May 23, 2014, 02:16:48 am
content: I tend to trust when people who have radio operator licenses are saying don't mess with a band you're not allowed to use.I would have to say that as a rough estimate 90% or more of the countries in this world do not allow "regular people" to set up devices (other than cell phones and the like) to operate on cellular bands.Even things like using Channels 12 to 14 on a wireless router could get you in trouble in all of North America. Channel 14 is not legal for use almost globally except for Japan which it is only licensed for 802.11b usage.This is not a "Woo hoo! I'm an American! Yee haw!" thing.

author: vk6zgo
author_rank: Super Contributor
timestamp: May 23, 2014, 05:13:50 am
content: Especially as I'm the person who said "probably illegal",& I am most definitely NOT American!By & large,throughout the World,regulations are similar to those of the USA,or Australia,for that matter.It isn't because the USA is the "Big,Bogey Man",but because there are International treaties about communications,which the USA has to abide by,like every other country.There have to be,as many countries have land borders,& even UHF/Microwave RF is no respecter of such.Also,note the meaning of"probably".It means it islikelyto be illegal,not that it definitely is.Even if,in your country these devices are legal,DIY ones are very unlikely to be so.

author: ejeffrey
author_rank: Super Contributor
timestamp: May 23, 2014, 05:42:58 am
content: Also, this is a thread from 2012 that was resurrected by someone with 1 post, so presumably the OP isn't even paying attention.

author: vk6zgo
author_rank: Super Contributor
timestamp: May 23, 2014, 06:01:10 am
content: OOPS!

author: AlfBaz
author_rank: Super Contributor
timestamp: June 03, 2014, 02:03:24 am
content: Quote from: ejeffrey on May 23, 2014, 05:42:58 amand that someone joined and posted on the same day and has spent a total of 5 minutes on the forum.The company they refer to has their website by a mob registered in Shenzhen

author: GeoffS
author_rank: Unknown
timestamp: June 03, 2014, 04:40:01 am
content: Quote from: ejeffrey on May 23, 2014, 05:42:58 amActually the original poster came back (as another user) and added a (since deleted) post presuambley to push a link in their original post. Links to the site removed from all posts.