Before begin. Where i stay is a rural area., cell phone signal reception is a nightmare. 1 bar or no service, the best i can get is 2 bar. After a long searching for a solution, trial and error. Discover this simple solution without purchased a expensive 3G signal booster. Here the guide to build one from household items.

DIY 2G/3G/4G wireless cell phone signal booster is a home-brew booster which uses common household items. This DIY can improves the signal of cell phone signal inside your house, from 1 bar to full. You need to build 2 unit, one indoor, one outdoor, both unit is similar and simple to build if you follow this guide, but i take few hours to R&D. I name it, LauC2 antenna. Before we start, safety first wear protector eye glass and safety gloves. When you see the bold text, is special for people want details instruction. This project can build using material you can found, finished LauC2 antenna have to 80% like the photo. Primary objective is E GSM 900, 2G signal reception. You need at least have cell phone signal coverage at outside your house for this antenna to function and working, 1 bar signal strength or come and gone.

Use the phone as usual, not wired. No wire connected to your phone.


First get all this items from your house :

  1. iron wire from clothes stand / wire coat hanger, [double check using a magnet is iron], 2-4 mm iron wire. Or you can get iron wire without paint coating to improve efficiency.
  2. two piece extend electric cable connector block, 20A [if any]
  3. common cable TV cable / coaxial cable / satellite TV cable, 30 meter good quality coaxial cable , no cut and joined.
  4. wire cutter
  5. pliers
  6. screw driver, 3-6 mm phillips screw drive and slot screw driver.

You can found all this items at your nearby supermarket, hardware shop.

Step 1: Start Building Antenna, LauC2 Antenna

Look at the drawing. First section we going to build is the 3G antenna using the iron wire from the clothes stand /wire coat hanger, the black color drawing. Not necessary to remove the paint coating.

Straiten the clothes stand wire / wire coat hanger with pliers [ i using hand ] and bend it 4cm at the corner about 45 degree.

  1. Then measure 8cm from the bend and bend inwards at 90 degrees.
  2. Then measure 9cm from the bend and bend inwards at 90 degrees.
  3. Then measure 9cm from the bend and bend inwards at 90 degrees.
  4. Then measure 8cm from the bend and bend inwards at 90 degrees.
  5. Last bending is same as the first bland 4cm about 45 degree where install extend electric cable connector block, insert the connector block to the ends of the both end of the wire and tighten it.

All wire is connected inside the connector block. The 4cm area, clean/remove the clothes stand / wire coat hanger shield [paint coating]. You have to use the wire cutter to cut the wire. Build 2 unit. One clothes stand enough for building 2 unit this kind of antenna. Maybe take you 1-2 hours or less.

Next step is the wireless antenna, the orange and yellow drawing. This section we need to use the common cable TV cable. So first cut off the plastic jacket about 15-20 cm length, depend on the center core round / turns , if you planning for testing the center core round / turns, maybe good idea about 20cm. depend on the center core round / turns diameter. Now you can see the [metallic shield] like a spider web, cut off this metallic shield and look at the drawing again, the red line is the metallic shield to be installed. No waste. Just twisted down the metallic shield become a wire without cutting [cut it if too long ]and fit into the connector block at the red line and tighten, not necessary a U shape. Then back to the cable, cut off the dielectric insulator carefully, we need the center core for building the wireless antenna.

Back to the drawing again. About 5cm from the edge of the center core [ or start at plastic jacket edge depend on the length of center core ], we need to make 5 round / turns clockwise, E GSM 900 2G, we can do it using screw driver [ 3-6 mm phillips screw drive ], just bend the center core round and round / turns on the rod. Then straight the center core both area like the photo. Now we need to mount this wireless antenna to the 3G antenna. Look at the drawing how this done. Remember the edge of the center core wire have to joined the iron wire and tighten. Do not forget the red wire.

After some testing, B1-WCDMA 2100, 4G have to be center core 7 round /turns at outdoor unit, and center core 5 round / turns at indoor unit. Use your smartphone searching for the location have STRONG 4G signal to put the outdoor unit.

A good signal strength define is maybe a stable 3 bar 2G signal, not a unstable signal strength jump up and down too often. Probably take a while for getting the right place.

If you not very sure, just make it 7 round /turns at out door unit and 5 round /turns at indoor unit. If the signal strength still too weak, you can trial and error increase the outdoor unit the center core round / turns 1 at a time. 1 round / turns mean 1 complete circle.

So you need both edge [ cutting edge ] of the cable to be the wireless antenna. Better install the cable one end at the roof top or near roof top, open area. One end is inside the house, anywhere you like.

Completed assembly, both end of the TV cable have a finished LauC2 antenna like the photo.

When you finish building 2 unit of this antenna. One unit install at outdoor where you can get STRONG cell signal strength and the front [flat area] of the antenna have to face vertical to cell tower, somewhere. Adjust the LauC2 antenna until you satisfied with the signal strength, test using your phone, recommended phone set to 2G for antenna adjustment purpose. Stay away from any wire mesh, object blocking, wireless device. Can put inside house window where can get good signal strength. if your house have lighting strike history, keep the antenna at secure location.

Now the indoor unit, anywhere you like where you want to put the antenna. Recommended at height area and open area for better indoor reception [ or center of the hall ceiling], and the location you always busy with your phone and keep distance with the wireless router. Just one condition, vertical or horizontal. Why? you asking? Take your phone, if antenna is vertical, phone also vertical getting strong signal strength. 2G signal always have better cell phone signal reception, tested device Nokia 1110i, 3 bar or full . Lumia 635 2G can get 3 bar signal. Moving too far away from the Lau2C indoor unit antenna, signal drop, tested 20-25m still have 2-3 bar. 1-3m i get full bar using Nokia 1110i.Smartphone always having poor signal strength.

Take off your smartphone additional phone case, some phone case really weakening the reception. If everything all right, you can dial out and received income call, even the phone show weak signal inside house, all phone carriers do have a free call customer hotline, dial the number and listen the audio quality.

The antenna no insulation part should not touching the wall or electric conductor.

If you want some dB value, enter Field Test mode on your smartphone

  1. Nokia / Windows Phone, dial ##3282#
  2. iPhone, dial *3001#12345#*
  3. Android, access Settings>General>About Phone> Network or Status

Closer the value to -50dB, better the signal strength

<p>i just modified and attached my Dlink 2750E antenna with this antenna, so fast it show better internet experience., if have a solid concrete wall in between. Dlink 2750E is a ADSL WiFi-300N router. </p>
you mean for the indoor? can ypu show some pictures of it? thanks <br>
<p>Low Signal strength is a great problem for everyone. One should installed spymee http://www.spymee.in/signal-booster.html signal booster to increased cell phone signal upto 4 times.</p>
<p>Does not work for 3G Lau. Not sure how many twists</p>
&quot;absolutely Zero percent effect on 4g&quot;<br>I had all needed parts so tried it as a holyday project.<br>Attached it on a 10ft wooden stick verticaly and tied it on tip of the metal bars on the second floor roof clear sky no obstacles in between (no building or trees on that height)<br>Other tip of the antenna indoor and no effects -115dbm before and after not a single diffrence<br>On the roof i have -89dbm and something like 4.8 MB download speed.<br>And yes i tried to test different number of rounds/circles and diffrent positions<br>Just a waste of 5 hours of off day and a good story for old neighbors to tell each other about the crazy scientist or enemy of the people kind of spy trying to contact the aliens.
Haha thank you sir Hossien. I love the all new make your own death, waste a day, indoor/ outdoor skitzer lighting rod. Sry you had to tred through the labor. Theres no way that would work here in the USA. However CREDIT must be givin for his elaborate instructable
Hello <br>How make this signal booster for cell phone signal?
<p>sir....can i use this for boost 3g dongle signal.......</p>
Can i combine it with tv booster
is there some kind of official name for this antenna so that we can maybe try to analyze how it can be improved??
Sir if i can replace iron wire to copper wire
Hey so i have a cell antenna but it goes to my router can i use this antenna would it even be better then the one the internet provider brought me <br>
<p>Hi,</p><p>I have already made it. I used to get very weak 4G signals at home. Still I am getting signals of the same strength. Is there any way to test whether it is working or not? Or I need to make some changes, or change the position of the outdoor antenna.</p>
<p>sorry mr lau this project has no technical fundamentals, you didnt consider:</p><p>losses on coax and the benefict of the coax shield,</p><p>the wavelenght, or the sizes of the quad antenna,</p><p>the initial and final coils value related to working frequency,</p><p>the Zo and the proper insulated conectors for the working frequency.</p><p>may be this is working at your home with a strong signal outside,</p><p>but is pure chance in most cases.</p><p>if you could give us the source of information you got , or the calculation you did</p><p>before trying and error test, all we could appreciate it very much and improve it</p>
Great, the bad wireless reception in the mobile home is over.<br>Thanks :-)
<p>aazzaa u lauc antenna working?</p>
Hi.. we already made it, but it didn't work at all....we really disapointed.. is there any suggestion...? Here is my email: amelia.yoshepine@gmail.com
<p>hai is it working or not?</p>
<p>Hi Han Ching, I read your instructables. What I came up its 2x10.5cm and 2x14++cm chopsticks, they are just recycled wooden chopsticks. Using one 2.5mm hard copper cable, I go around, then cut another 2.5mm, coil it around a chopstick to make it like telephone cable. It's hard copper cable there, so coiling might take some effort. Thereafter, I use a double 1.76mm power cable, just unskin both cables(less than 1m), then twist them together. Receiver just throw outside windows, then tie the other end to my radio. </p><p>Yes, I hear all of you, no near to router, no near to microwave oven thingy. Problem is my DIY Ultimate radio (no need to charge for 1 month) is on top of a PC. When I switch on the PC, the radio becomes disabled due to interference. Now with this mini receiver, I could actually operate both the PC and radio at the same time.</p><p>Verdict: Yes, it works. Although it did not follow everything in the instructables, but here is something I did manage to find out. Since the radio antenna itself is also an antenna, not only wireless signal in the room gets a bit of boost, handphone signals becomes better too. Hee. 1 receiver 3 benefits.</p>
<p>Why would you ask that? It's not even remotely similar. </p>
<p>Where can I buy the two piece extend electric cable connector block? (link)</p>
Is it usefull for 4g network?
Dear Sir, I feel great to write you, I have figured out every thing but not Abel to find connectors could you please let me know another way to get this thing working without them?
<p>still no improvement in my mobile sir pls gudie me to improve the range of 3g</p>
Can i make the antenna in triangular shape instead of square
<p>what if i have outside antenna for broadband and the other side is the LauC2 Antenna, will it work ?</p>
<p>Hi Lau, I happen to have a Satellite dish connected with a coaxial cable but no decoder how can I modify this to boost 3G signal in my room?</p>
<p>what kind of metal will be best? aluminum, copper or iron ?</p>
<p>can i just use solid copper wire is it better or iron is better?</p>
<p>use what you can found</p>
Thank you<br>I want to know cable should be 30 meters absulotly?
<p>no. </p>
<p>You provide no theory behind this device, nor do you present any empirical data. </p><p>There are so many flaws in this design, for example; your coaxial cable is not even earthed, therefore provides no shielding; your antennas have no balun, so there will be an impedance mis-match with the coaxial cable.</p><p>Furthermore, statements like &quot;...you also can use your phone headphones work as an Antenna too...&quot; are incorrect; Phone headphones include an antenna for FM Radio frequencies, and do not apply to 3G.</p>
<p><a href="https://www.instructables.com/member/Lau%20Han%20Ching" rel="nofollow">Lau Han Ching</a> Dude, thanks for this. I've been looking for this a lot this past year. <br><br>My comment to this procedure is that the measurement should be precise for best result and the curly thing (Maybe it could be called trimmer) should have a proper measurement (diameter and turns) but I think just a nice turns would do. Man, if it's not too much to ask, can you share the link where did you get this design?</p>
<p>and another thing is use coaxial cable with less resistance ex. RG-8 50 ohm coaxial cable.</p>
<p>Nominal impedance of coaxial cable (50ohms for RG58; 75ohms for RG59 and RG6) is used for the purpose of matching the termination impedance of both source and load. Your statement is incorrect.</p>
<p>and i don't care how ugly the assembly look like, as long it work. </p>
Hi i want to know cable should be 30 meters.
To use the homemade antenna ,we need to use a wireless router too Mr Lau ?
<p>the idea is everybody can build it using whatever material found surrounding area without any high precision equipment. After so many online research, my inner voice told me to put all stuff assembly this way with material found surrounding me. SImple, right? </p>
Thanks.<br>I want know cable long should be 30 meters absoulotly?<br>
Hello Mr Lau,<br> Just tell me ,we need a wireless router too to use the homemade antenna ?
<p>No, this has nothing to do with wireless routers, it's just a way of increasing mobile phone signal inside the home.</p>
Thnks OronJ1,<br> But why Mr Lau mention KEEP DISTANCE WITH [WIRELESS ROUTER] ?
<p>Because of electrical interference. You should also keep it away from cordless phones (not mobiles) microwave ovens.</p>
<p>Whats the metallic shield (red wire), what wire should I use for making it?</p>
<p>Thanks, <br></p><p>I just built one for use with a mobile wifi <br>hotspot, that had such lousy reception, most often couldn't load more <br>than 2 webpages without it timing out or getting constant server errors,<br> (despite indication getting 80-100% signal) and having to turn it off <br>and on again to get it to work for that or each time, It's still slow, <br>but so far getting less error messages, or quickly loads a timed out <br>page when retrying</p><p> My cable is near 40' hanging outside on a 12&quot; tall TV antenna, on top of a Motorhome so 20' + high. I<br> soldered the connections, (not very well) but only to one wire hanger<br> piece,(that is outside) using a piece of the left over cable shielding <br>for the metallic shield bridge (of which I don't see much detail about <br>in the instructions) My other end is just the coiled wire taped to beck<br> of my mobile wifi hotspot unit....as seen in another version of this <br>to the back of a cell phone , (I used 7 coils on both ends ) I might <br>eventually try attaching the other wire hanger to it, either soldering <br>or some other method... Looks like could just make the wire core longer <br>and wrap around both those inside ends of the wire hanger unit. secure <br>by zap straps or better to clean and solder it ....if not some of the <br>solder that comes in a glue tube form.</p>
sir, what if i dont have a cable connector block,? any alternative solution or alternative object that i can use..?

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