Low signal in metal building

[subhumanderelict]

Originally Posted by bakntyme

WARNING: boring technical info below
If you want to try the external antenna anyway, antennas are tuned by adjusting the length of the antenna; it should be an integral multiple of half of the desired wavelength. The wavelength is the speed of radio waves, which is the speed of light, divided by the frequency; so a frequency of 1900 MHz would have a wavelength of approximately 0.15789 meters, or approximately 6.216 inches. Therefore, an antenna of a length that is a multiple of 3.108 inches would provide the best signal.

See Wavelength and Frequency, Univ. of Oregon

You're right; this would be worth a shot too. For high frequencies, it's mostly dependant on the dimensions of the antenna. I just hope the OP doesn't mind if this thing doesn't work after this, in case something goes wrong.

[tenpinmogul]

I'm a tinkerer so don't mind trying to make something when I'm able before I go out and buy one, especially if there's a chance it won't do any good. And if I break something, then that's my fault. I do try to take it easy on the external antenna plug when I use it, so hopefully won't have any problems with that.

I have tried 2 different antennas, one 6.2 inches and the other 3.1 inches in length, each having a coil bent into them that was 5 turns. At first the 3.1 inch antenna seemed to be helping, I was getting 1 - 2 bars instead of 0 - 1 bars. But then a few hours later I went back to messing with it and was unable to repeat this, my signal stayed at 0 EV bars sometimes bouncing to 1 then back to 0. So I don't know if the antenna really did anything or if it was just a random case of the atmosphere being more cooperative. The one thing I haven't tried yet with my antennas is to add a ground plane of some sort, I might try that today. If that doesn't do anything, I will probably give up and just live with it as it is.

[shaggylive]

I use this on my van http://www.wpsantennas.com/index.asp...ROD&ProdID=470
* Operates simultaneously on 7 bands (AMPS/Cellular, IDEN, GSM, GPS, DCS, PCS, UMTS, ISM/WiFi)
* Compatible with all US Cellular and PCS providers, supports overseas frequencies as well
* Multiple NMO mounting options are available (sold separately)
* Metal ground plane required
* Patented Field Diversity US Patent Numbers 45,977,931 and 6,292,156
* Patented PC Board radiator
* Phantom patented true field diversity design ensures uninterrupted transmissions in urban canyons and rural drop off areas - counteracts signal fading in reflective or mobile environments
* 3dB MEG gain outperforms a 3dB whip in many applications
* Solid construction: ABS material is injection molded directly around the solid brass insert and all silver soldered joints
* Specified by public safety, military, utility and transportation providers and installed on Apache, Black Hawk and Chinook helicopters and Humvee and Bradley military vehicles around the world.

I have actually seen this on Offical vehicals as well.

it's only an inch tall and 3db, but I would think in a building a tall antenna wouldn't have enough "room" for it's pattern

[holo]

FYI that 2.4ghz antenna will probably hinder you more than help. It is built specifically to receive 2.4ghz signals. If you are really interested in getting it to work a real cell antenna will probably work wonders for you and on the plus side if you leave the company you can attach it to your car afterwards for roadtrips through low signal areas

Also, I don't believe it's only the length of the antenna which sets it up to receive certain frequencies, there is more to it than that (IIRC spacing of the coils/etc)... You can certainly find antennas of different lengths built to receive the same frequencies.

[subhumanderelict]

Originally Posted by holo

Also, I don't believe it's only the length of the antenna which sets it up to receive certain frequencies, there is more to it than that (IIRC spacing of the coils/etc)... You can certainly find antennas of different lengths built to receive the same frequencies.

This is what I had originally thought (see previous post), but I had consulted someone who worked a lot with electromagnetics and he said that as you approach GHz-range frequencies, the size of the antenna becomes the prevailing factor.