*
Finishing an ICF house. Outside, my truck picks up several great stations. Inside the house a Sony boombox picks up one station with the antena up and a different one with the antena horizontal. I played with stringing some 14g wire from the radio all over the place and different shapes to try to get some improvement, including out the window, with little success.
Any good ideas for better reception? Anyone build antenas into a house? Is there any rhyme or reason to it, or just jiggle the rabbit ears like the pre-cable days.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Tips for protecting your personal information when using Wi-Fi-connected devices.
Featured Video
SawStop's Portable Tablesaw is Bigger and Better Than BeforeHighlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
*
All building materials attenuate radio waves, and metallic ones reflect them away. The chicken wire in stucco is a pretty good RF shield at AM frequencies, less so at the higher frequencies of FM and TV. An ordinary UHF Yagi TV antenna placed outside should work fine for FM radio, which lives between TV channels 4 and 5 IIRC. It sounds like this house is fairly far from the transmitters.
-- J.S.
*teo,Get some 300 ohm twin lead to make a dipole antenna. Looks like a T. Split the lead 28.5" down the center. This is the top of the T. Twist the bottom of the T alot and hook each wire on bottom leg to radio. The higher mounted the better. Perpendicular to station.KK
*It's been a while since I took any courses on electromagnetic radiation, but I think the technical term for the effect of rebar surrounding a room is a Faraday Shield. This is where a grounded metal cage is put around something and functions to shield its interior from radio waves. Not that you really needed to know that...I assume that there is no metal roof, then it would seem that you should still get some radio waves in the room, although they would be diminished near the walls containing rebar. If you were unable to improve reception by hanging a wire out the window, then either you were on the "downwind" side, away from the transmitter, or something else is wrong. And, yes, a lot of people still do antennas - particularly amateur radio nuts and DXers (people who like to pick up stations a long distance away). If you want to improve A.M. reception, then a long wire antenna (sort of a giant version of sticking the wire out the window) should help (even if there is no antenna connection on the radio, you can wind a wire coil to couple to the internal rod or coil antenna.) For F.M., you can use the type of dipole antenna mentioned above or just go down to your local Radio Shack store and buy either a wire dipole or an aluminum FM antenna. You can also build into a house a powerful receiving antenna called a "rhombic". These are highly directional, so must be pointed in the direction of the radio or TV station. If one of the corners of the house points toward the station(s) that you are most interested in receiving, you could just tack the wire along the edge of the roof and run the lead in from the corner opposite where the transmitter is. If not, then you would have to build the antenna into the roof above the level of any extensive metal. There used to be a pretty good description of a rhombic antenna on-line.It's been a while since I built any antennas, but there used to be a number of resources on-line on Antennas, mostly on Amature radio oriented web sites. Most libraries have old books giving detailed directions on building antennas. The basic styles of antennas haven't changed in quite a few years.And just because the boom box is a Sony doesn't mean that it has the best fringe area reception of any radio. It is very possible, even likely, that your truck radio has better distance reception than the boom box. I have a cheap 5" color TV that gets better fringe area reception than my spiffy 32" Sony TV - however, in a strong reception area, there is no question that the Sony is far superior to the little one.
*reception vs. sound quality Car radios can sacrifice some sound quality due to the noisy environment they are used in (the customer can't hear so well that there is less stereo separation, more distortion or less bass and treble, etc.). Also, your vehicle moving accross the ground crosses many nodes and anti-nodes that are produced by things that interfere with the signal path so that you tend to hear an 'averaged' signal (you notice this when stopped at a light and your distant station comes in and out as you roll to a stop).home radios don't move around while you listen to them so don't get the benefit of that averaging. Also they are designed for listening to in a quiet environment and good speakers, so have sacrificed some reception for maximum sound quality.I may have some of the detials fuzzy (not an EE) but this is what I remember from college about why car radios often sound 'better' than home radios in difficult reception areas.
*And now you even have the option of saying forget conventional radio and going to the satellite radio. It's really a neat thing.
*
Finishing an ICF house. Outside, my truck picks up several great stations. Inside the house a Sony boombox picks up one station with the antena up and a different one with the antena horizontal. I played with stringing some 14g wire from the radio all over the place and different shapes to try to get some improvement, including out the window, with little success.
Any good ideas for better reception? Anyone build antenas into a house? Is there any rhyme or reason to it, or just jiggle the rabbit ears like the pre-cable days.