Ask MetaFilter posts tagged with antenna

What antenna should I buy to broadcast a wireless signal?

jammnrose — Fri, 29 Aug 2008 14:00:52 -0800

I'm looking to broadcast a wireless signal 100-200yds. How many dB/mW does my antenna need to be and what's the optimal frequency? I'm looking to broadcast a wireless (802.11x) signal 100-200yds. How many dB/mW does my antenna need to be and what is the optimal frequency? Where can I buy an antenna to do this? A directional antenna would be best, right?
I did find this site, but I was wondering about a better place to get an antenna...

Thanks in advance.

Why the DTV lag?

middleclasstool — Thu, 07 Aug 2008 08:04:43 -0800

Why does a tv station's digital signal lag behind its analog signal? We're one of those annoying families that refuses to pay for TV. We forked over the cash for an HDTV with a digital tuner, and absolutely love the results -- more channels, better quality, total freeness.

But we've noticed a weird thing. Our other two TVs are still on rabbit ears. One of them, in the kitchen, is well within earshot of the HDTV in the living room. Yet if we have the same show on both TV sets, there is a distinct lag, not more than maybe two or three seconds, between the two shows.

This happens on all networks, so I know it's not a channel-specific thing. I haven't timed it, but I'm positive the lag is precisely the same length regardless of the channel, too.

Is there a technical reason for this lag to occur? I know the DTV signal is actually being transmitted on a totally separate frequency (channel 2's digital channels, 2.1-2.4, are actually broadcasting on channel 5's frequency, for instance), so what could be the reason for the delay?

Human (And Dog) Antenna

amyms — Sun, 25 May 2008 11:01:22 -0800

A question about how our bodies affect radio reception... We have a stereo in our living room that has poor radio reception. It is plugged into a power strip that is in turn plugged into a wall outlet (an inner wall, if that's important). It doesn't have an antenna.

Whenever one of us walks by, the reception gets crystal clear, and significantly louder. It reminds me of when I was a kid and we could get clearer reception on the television by holding the "rabbit ears" in our fingertips. But, with the stereo, there's no one touching any part of it when the phenomenon occurs. It even happens, though not every time, when our dogs walk by (they're both small terrier mixes, if that matters), but not when the cats walk by.

I understand that our bodies can act as antennae, but how does this work, especially when simply walking by the stereo without touching it?

How to fix loose portable radio antenna?

JanetLand — Wed, 14 May 2008 05:39:58 -0800

Portable radio antenna is loose and falling over. Can I fix? I have a Sony ICF-SW7600GR radio that's about 6 months old. The antenna has suddenly begun flopping over instead of staying standing straight up. It does this whether or not it's fully extended. Obvious dirty jokes aside, what's causing this? I tried tightening the screw that seems to be holding the antenna in at its base, but it's already tight; I couldn't budge it. And yet the antenna seems loose, not at the hinge portion, but loose in its connection to the radio, if that makes sense.

aerial antenna for high VHF/UHF

Zed_Lopez — Tue, 06 May 2008 12:49:16 -0800

Appropriate aerial antenna to receive high VHF and UHF across 12 miles? After the US digital TV switch, all the tv stations I want will be transmitting on channels 7-44 from one tower 12 miles WSW of me, without obstruction, so far as I know.

Antenna geek sites are full of recommendations for things that seem to be overkill for these close-to-ideal conditions. What's the best bang-for-the-buck aerial antenna (i.e., the cheapest one expected to yield excellent reception) for these circumstances? (Assume I can figure out how to mount it on my roof pointing in the right direction.)

Help me hook up the VCR to the TV along with our new digital converter box.

IndigoRain — Sat, 03 May 2008 22:38:08 -0800

Help me hook up the VCR to the TV along with our new digital converter box. I don't care that the VCR can't record or display digital channels - I just want to be able to watch videos and DVDs. I bought an Insignia NS-DXA1 digital converter box for my TV. Now the VCR-DVD player (a separate unit from the TV) won't work. (I don't have satellite or cable, just broadcast.)

1. I tried running the antenna coax cable from the wall to the IN on the converter box, and another from the OUT on the converter box to the IN on the TV. TV works fine. VCR has the red, white, and yellow composite cables running from the OUT on the VCR to the IN on the TV. TV will not get a video or DVD display or audio from the VCR with the converter box on or off.

2. I tried running the wall cable to the IN on the VCR, another coax from OUT on VCR to IN on converter box, another coax from OUT on converter box to IN on TV. Nothing worked, with all combinations of VCR and converter box on and off.

The TV is old enough that it only has one antenna input and one set of composite inputs, and one set of red-white audio output (which I assume are for external speakers.)

The converter box has one RF output and one red-white-yellow output.

If it helps, I do have an AV source selector box (something like this but most definitely not that model) because on my old TV, I needed it to hook up my multiple gaming consoles. It is currently not hooked up because on this TV, I simply had my PS2 run through the VCR. I unhooked the PS2 before trying to set this all up.

I'm at a loss. I'm NOT paying Geek Squad or the like $150 or more to come out here and hook it up - I can't afford it. I can't afford to buy a DVR either. Any help is appreciated, or I'm just unhooking the converter box and praying I can afford a digital TV by 2009. (With gas and food prices going up, I'm pretty well completely broke.) Please help me figure out what to plug in where!

Best tuner for Windows Media Center 2005?

lattiboy — Thu, 01 May 2008 01:57:34 -0800

What are the best ATSC tuners to use with Windows Media Center 2005? I'm starting over with my media center PC (I have the worst cable company in history) and want to do it right. I've got a rig with a
500GB HD, an Nvidia 7300 with HDMI, a Gyration Media Center remote, the AntennasDirect DB2, and now I just need to decide on tuners.

I had the Hauppage 950 USB tuners before, but performance was nominal at best. I think I want to go with external or PCI tuners this time, but am open to USB. I thought about the HdHomerun, but I'm not going to be using QAM for awhile (till I move) and it lacks an analog tuner.

Please keep in mind I'm looking for 2 ATSC tuners and at least 1 analog tuner to meet MCE requirements.

PS Any extra advice for the setup (besides "Just use MythTV!") would be appreciated.

Thanks!

Long Range Wifi Cards with Mac OS X?

Freen — Tue, 07 Aug 2007 08:36:10 -0800

Wifi Shootout: powerbook g4 PCMCIA: what card and antenna combination will get me the most bang for my buck in terms of range? I'm looking for that rare, high powered wifi card that has the necessary connectors to attach an external antenna, such as a cantenna, that has functional Mac OS X drivers. Ideally, really badass drivers that let you change power output, antenna diversity, etc.

Also, any ideas on antennas? Is tha cantenna worth it? or are there better, cheaper directional options?

thanks!

Better boombox FM reception?

CwgrlUp — Thu, 02 Aug 2007 07:56:42 -0800

How do you get better FM reception from a boombox? I have a relatively inexpensive Emerson boombox at work. Needless to say, it has no external antenna jack. I'm in the center of the building with florecent lights all around and reception is crap. How do I rig some kind of antenna? (Can't put anything on the outside of the building or anything like that so it has to be indoors.)

What can I do to improve my cellphone reception indoors?

Kickstart70 — Tue, 02 Jan 2007 13:50:55 -0800

What can I do to improve my cellphone reception inside my house, and not one of the scammy crap things than I see available in spam and Google searches on this subject? My cellphone works generally ok outside the house, but once inside I can't even make a phone call. I often end up standing inside with my head outside the door to have conversations with people. My wife's cellphone does the same thing (maybe slightly better than mine).

We don't have a landline, and use Skype for long distance, so I -can- make calls from inside the house. However, when I want to call a Canadian 1-800 number Skype fails. Our living space is a groundlevel suite, about 20 years old, and has some metal interior framing, which I suspect is part of the problem. Additionally, our wireless baby monitor has piss-poor reception as well.

Is there anything I can do? FWIW, my phone is an LG6070.

Uni? Multi? Whip? Band? Huh? Wha?

id — Sat, 30 Dec 2006 12:58:58 -0800

WIFI-Filter: My brother and I would like to build a wireless network between our two homes to create a secure network, but we have no idea about radio antennas, signal strength, line-of-sight, etc. The situation: My brother lives ~1900 feet away (about 4 blocks), and about 30 feet above me in altitude. In between are the normal manner of houses, apartments, trees, etc.

We do not have direct line of sight.

What type of antenna and how strong of an amplifier would we have to pair up in order to create a strong, fast wireless link between us? Is this even feasible? Is it even nice, considering we'd have to steal away a whole channel from the spectrum?

GPS unit is not exactly accurate. Is this normal?

D Wiz — Tue, 12 Dec 2006 15:17:56 -0800

GPS unit sometimes is sometimes a bit inaccurate... Is this normal? I am new to GPS and am having problems and I was wondering if any of these are normal (using the mio C310x)?

Sometimes when I arrive at my destination it will tell me to make a left in the opposite direction from my destination another 60ft (the destination is on my right). Is it supposed to be 100% accurate? Or do GPS units tend to be a bit off? (It also tells me that my apartment is 4 or 5 buildings down from where it really is.)
Is this normal or is the unit broken?

Another problem I had is that I went downtown and the GPS kept losing my signal and rerouting me over and over again. There were tall buildings surrounding me if that matters. It kept telling me I was on the wrong street (ie. it would tell me I was on 5th st. when I was on center st.) Also, it sometimes would tell me to go left and a split second later tell me to go right (when there were no streets in between. It seemed a bit confused).
Someone told me that this is called bounce. Do all GPS units have trouble in that kind of environment? Is there anything I can do about it? Will getting an external antenna help?

Products to boost laptops wifi range

ZackTM — Wed, 06 Dec 2006 19:50:13 -0800

Best way to get long range access to hotspots? What is the easiest, best way for me to extend the wireless range of my laptop? I have an internal wireless card which i can't get access to without completely opening the case up. I don't mind buying an external wireless card and an external antenna but don't want to spend an arm and a leg. What products are my best shot?

I will be using this to do everything from accessing my home network around the neighborhood to getting emergency access to the internet when i'm on the road and urgently need some information.

Do over the air antenna amps work?

wfrgms — Sat, 25 Nov 2006 16:45:01 -0800

HDTVfilter: Have you had success with over the air signal boosters or amplified antennas? I moved recently here in Chicago and lost about ten of my over the air HD channels. I think it's because my new apartment is tucked between two mid-rise buildings where as before I had a good line of site view of downtown (where I assume all of the broadcast towers are.) I'm just under two miles north of downtown so distance isn't the problem.

I use an indoor passive (non-amplified) antenna like this one. The channels I'm missing all score somewhere in the 30 to 60 dB range, so they are unwatchable... I've found in general I can't tune a channel unless I get in the 75 dB and up range.

Tonight at Best Buy I looked at an inline booster which claimed a 10 dB increase ($39) and several amplified antennas which claimed 20 to 30 dB increases ($50-60)... should I invest in one of these? (Unfortunately I don't think I can install an outside antenna in my current building.)

I've read through most of the HDTV OTA questions but I haven't found any that specifically address either amplified antennas or separate in-line amps.

What I'm wondering is if I buy an antenna or amp that claims to boost the signal by 20 or 30 dB will I really see my 60 dB reception jump to 90 dB? Thanks!

What’s on the pole?

Tenuki — Tue, 03 Oct 2006 14:43:51 -0800

Can anyone identify the device on this pole? These poles are located every couple of miles along the Washington side of the Columbia River between Plymouth and Goldendale. At first I thought they might be some kind of antenna for the agriculture businesses or barges on the river but then I remembered that the Umatilla chemical weapons depot is right across the river and wondered if they might be some kind of chemical detectors. Does anyone know for sure?

How can I decrease FM reception for my car?

poppo — Thu, 28 Sep 2006 10:42:20 -0800

How can I decrease FM reception for my car? I have taken off the antenna, but would like to proceed further. So, I have a new Sirius receiver and it broadcasts over whatever FM frequency I choose to my car radio. However, my area seems to have a lot of stations, with strong signals, so I get a lot of interference.

Obviously, I can just hardwire the receiver to the radio and this will solve my whole problem, but I was wondering if there was another step I could take in reducing the FM reception. Removing the antenna helped, so I was wondering if obstructing the remaining base it screws into would help. What material would dampen FM signals? Can I effectively reduce FM signals from the outside world but not one coming from inside my car, or is my whole car one big antenna?

One TV antenna per town?

washburn — Sun, 24 Sep 2006 20:31:55 -0800

Why can't a community use tax $ to put up a single large television mast antenna and allow, say, the 100 highest bidding networks to broadcast, all from that same tower? I just don't understand why there need to be so many tv broadcast antennas around town, or why I should have to pay for cable or satellite in order to recieve more than a few channels. Shouldn't there be a more efficient way of getting television to people?

Replacement antenna for Kenwood TH-2KAT

Godbert — Tue, 01 Aug 2006 13:25:47 -0800

Where could I find a good replacement antenna for a Kenwood TH-K2AT ham radio? After lugging the radio around in a bag for a few months, the cover for the original antenna began to crack. Since then, some chunks of it are gone, leaving the inner part of the antenna exposed. Ideally, I'd just like to replace it with a new, identical antenna, but it doesn't look like Kenwood (or any of the online places I checked) carry it.

What other antennas (antennae?) would be the best replacement for the included one, considering that this is not for any power-use of it (in fact, I usually only use the included antenna when I'm using the radio as just a receiver; I have a mag-mount antenna in my car for when I'm on the road). I'm basically looking for the best 1:1 match for the old antenna in terms of size and quality; I don't need or want a six-foot-long antenna since I'd be walking around with it.

Additional details for those who may be unfamiliar with the particular radio: the antenna is about six inches tall, SMA mount, for the 2m band.

What do I need to know to plug my TV into my neighbour's antenna?

teem — Tue, 25 Jul 2006 04:39:33 -0800

What do I need to know to plug my television into my neighbour's rooftop television antenna? My place doesn't have a television antenna on the roof so I use a small, crappy antenna. My neighbour's place has a rooftop antenna that the previous owners installed. To install an antenna at my place will cost more money than I have.

My place is one of a few townhouses made from a much larger house. So, between me and my neighbour's place is a single wall. They have agreed to let me run a wire from their antenna to my house, providing I deal with everything.

Will doing this weaken their signal? How do I get around this? Are there any serious problems with this idea? If so, how do I get around them? What do I need to know?

Hack my PowerBook an antenna

skylar — Mon, 19 Jun 2006 05:37:50 -0800

How might I attach my (broken) wi-fi antenna to my PowerBook, or to a (non existent) PCMCIA wireless card...? I have an old Lucent wi-fi antenna, which (back in the early days of 802.11b) I used to attach to an external PCMCIA wi-fi card.

Nowadays I use an old PowerBook G4 and its internal wi-fi most of the time. But there's no way for me to attach the antenna for those times when I need it. The PowerBook has a PCMCIA slot - but I don't have the accompanying wi-fi card, nor do I have appropriate drivers.

To make things more complicated still, the little attachment at the end of the cable on the antenna has partly broken off.

Is there a way to hack something together? Should I buy another antenna? Can I buy the little metal attachment to replace the broken one on the antenna? Is there another wi-fi PCMCIA card or USB card I could buy which would work with the existing antenna?

What is this arena show device?

valleys — Wed, 17 May 2006 08:38:57 -0800

I'm curious about equipment seen at larger concerts: opaque plastic (?) disc, clear plastic tube attached to one side, spiral wire around the tube, cable coming out of the other side of the disc. Some kind of microphone? I go to lots of club & theatre concerts, and just the occasional arena show. I can usually figure out the purpose of most of the equipment on stage, but at the last 3 arena shows I've been to I've noticed the object described above and have no idea of it's purpose. It's always on the right-hand (as viewed from the audience) side of the stage, on a stand about 6'-7' high. The disc and open end of the tube face the stage. I'd estimate that the disc is 8"-12" across, the tube 6"-8" long.

I'm guessing that perhaps it's a surround sound mic, or an ambient mic? Or maybe something to do with wireless mics/in-ear-monitors? I've tried various google & google image searches and can't find anything.

What are the mobile govenment antennas?

Etaoin Shrdlu — Mon, 10 Apr 2006 10:15:45 -0800

What was the big antenna attached to the federal government pickup truck? This morning on my way to work (across the Richmond bridge, CA), I was behind a pickup truck with federal govenment plates that had a big antenna array on a mast stuck through the roof of the cab. I believe that it was a Yagi array (I don't know much about antennas, but in my quick search through the net just now that's what they looked like). On each side (left and right of the cab) there were arrays of five parasitic elements attached to the dipole (I don't know if these are the right terms for these parts but I like the big words I find on Wikipedia). On the left side, the elements were perpendicular to the dipole; on the right side, they were set at about a forty-five degree angle. The whole array could be rotated around by hand with a handle attached to the boom inside the cab.

So what is it?

Broadcast HDTV reception problems

putzface_dickman — Wed, 15 Feb 2006 09:28:06 -0800

How can I fix my broadcast HDTV reception problems? I just bought a used DirecTV set-top box that receives ATSC, or broadcast digital, signals. I found a deal on a Toshiba DST-3000[pdf]. I picked it because it was the cheapest I found that received DTV. I get through the setup fine, scan for channels, and it finds only a few of the 8 analog signals available and only one of the 6 digital signals available. When I tune to the signals it did detect, or look at the signal strength meter on the setup display, there's basically nothing except for one channel where I can almost make out that there's a picture.

I'm using standard, unpowered VHF/UHF rabbit ears which allow me to get every local analog channel when I connect it via coax to either the VCR or TV's tuner. I've chained the digital receiver to the VCR, to the TV via coax. I've also tried using RCA connectors all the way. Nothin'. Whether the digital receiver is turned off or on if it's in the chain and I try to use the VCR or TV tuner I can't get any of the channels that I normally get clearly with this set of rabbit ears. This is true of both VHF and UHF. The farthest broadcast tower is no more than 10 miles away. The rest are about 6 miles.

I bought this box because I read that even crappy reception rendered great pictures with DTV, plus I'd add some PBS channels. There's no DirecTV Dish attached. I don't want cable or sattelite. I don't want to spend $200 plus on a purpose built ATSC receiver when this $70 box should have the same functionality.

I've looked at this previous question.

TV antenna towers

rolypolyman — Fri, 10 Feb 2006 13:25:18 -0800

Where do you get those little 30-foot TV towers, that look kind of like this? They're all over the place out here in rural Texas, but I don't have any idea where people get them. They can't be ham radio towers, as I've bought those before and they run close to $1000. I just want something to get my weather station wind sensors up over the tops of the pine trees.

How to pick an HDTV antenna?

gyc — Tue, 06 Dec 2005 10:43:08 -0800

HDTV Antenna question: My folks are getting a new HDTV delivered in two weeks or so. Their local cable company doesn't offer all of the local networks in hi-def so my folks are thinking of getting an antenna in the attic to pull in the rest of the local hi-def signals. Does anyone have an indoors antenna system that they are happy with for pulling down HDTV? I have used AntennaWeb and tried reading the antennas forum at AVS forum but it just ends up confusing me even more. How well do rotators work and is it worth the extra cost? Are the "HD antennas" at Radio Shack adequate or do I want something else? Is there anything else I need to know?