HDTV Antenna Amplifier Circuit

[gone2fly]

I have built a good antenna for my HDTV that works great the TV signal strength meter reads 95% to 98% most of the time. I use to receive 6 channels with the factory antennas now I receive 24 channels with my antenna. I have noticed Digital TV is affected a lot by strong gusty wind. Also every day when the sun is on the horizon TV signals are poor. We have been having gusty 30 mph winds for 3 days so TV signals have been very poor for 3 days. My antenna is outside on a tripod in the back yard about 20 ft up, house and yard are on a slight hill above other houses in neighbor hood. Antenna is adjustable through 150 degrees for all the TV stations located within 60 miles and the antenna is mounted ridged top and bottom so it does not wobble or shake in the wind. I bought a Radio Shack antenna amplifier and it helps, it boosts my signal about 25% but I need more. The antenna that I built is a quad screen bow tie, 4 antennas 20" x 30" each connected together. Antenna was built exactly like the antenna is Amature Radio Antenna Handbook.

I need a solid state amplifier circuit for HDTV to boost my antenna signal.

I had cable TV once the rates kept going higher and higher when it got to $60 a month for basic service with 30 channels of advertisements I cancelled it.

I had Direct TV once problem was about 45 channels of worthless advertisements and the pay channels had advertisements too. They plays the same movies over and over and over and over and over I got tired of paying $60 a month to watch the same movies they have been showing over and over for 2 years so I cancelled. I cancelled my service and the single went off. I disconnected the converter box and hooked up my antenna. 3 days after the signal was turned off Direct TV turned it on again but I didn't know that I was using an antenna. 6 weeks later I got a bill for another month of service. I refused to pay for 2 years finally a collection agency took it out of my pay check. Hell will freeze over before I every have Direct TV again.

I am getting some very good TV channels with my antenna, movies, NPT, nature channel, travel channel, local channels, I'm just having a problem sometimes when it is windy and when the sun is on the horizon.

 

[blueroomelectronics]

What antenna are you using, how high and where is it mounted?

 

[gary350]

What is your geographical location?

 

[Nigel Goodwin]

And what has been HDTV got to do with it?, there's no such thing as an 'HDTV aerial', or for that matter a 'digital aerial'.

 

[HiTech]

Oh come now Nigel, haven't you been educated by the marketing brains at Radio Shack and similar consumer electronic outlets about "digital ready antennas" just like digital speakers, etc? The last I knew, speakers were still operating off of analog signals. LOL Radio Shack has a few pages worth of HDTV antennas on their website. Bottom line is I guess the mfgrs. try to make them look digital so consumers feel convinced!
I get a real kick in the pants when I see these folded dipole antennas that clip to a small TVRO dish to receive local off-air broadcasts. The mfgr. likes to label them as HD ready!! WOOT!
And when's the last time any of us heard analog audio sound any better when using gold plated connectors versus standard nickel-chrome ones? Even my Tektronix scope can't show me that one! There's only been one mfgr. I know of that produced a piece of hi-fi gear that employed gold connections from start to finish throughout its entire list of internal componentry that involved the signal path: Audio General

 

[RadioRon]

I have noticed Digital TV is affected a lot by strong gusty wind. Also every day when the sun is on the horizon TV signals are poor. We have been having gusty 30 mph winds for 3 days so TV signals have been very poor. My antenna is outside on a tripod in the back yard about 20 ft up, house and yard are on a hill above other houses in neighbor hood. Antenna is adjustable through 150 degrees for all the TV stations located within 60 miles and the antenna is mounted ridged top and bottom so it does not wobble or shake in the wind. I bought a Radio Shack antenna amplifier and it helps it boosts my signal about 25% but I need more. The antenna that I built is a quad screen bow tie, 4 antennas 20" x 30" each connected together. Antenna was built exactly like the antenna is Amature Radio Antenna Handbook.



I an getting some very good TV channels with my antenna, movies, NPT, nature channel, travel channel, local channels, I'm just having a problem sometimes when it is windy and when the sun is on the horizon.

The affect of wind on your reception cannot be a problem of propagation, as wind does not directly affect EM waves. However, wind could be causing a source of multipath to move which could vary your received signal level, but this is not very likely. I believe that the reason that wind is giving you trouble with reception is that there is some sort of loose connection or microphonic issue in your outdoor equipment, either the antenna itself, the feedline, or the amplifier. Most likely source is that you have a loose or noisy cable connection that is vibrated by the wind or that some part of your actual antenna has a flaky connection.

Another possibility is that the antenna beam is shifting due to antenna movement in the wind. However, the quad bow tie is reasonably generous when it comes to beamwidth in both horz and vert direction, so very small movements in the antenna are not likely to change signal levels.

I also wonder why you would need additional amplifiers when one is probably enough. Your receiver probably has good sensitivity and the point of the antenna amplifier is mainly to lower the system noise floor to make up for transmission line losses and any discrepancy in receiver sensitivity. How long is your cable from antenna to receiver and what type is it? I don't think another amp is going to do much good if your RadioShack one is suitable for UHF and is working correctly.

 

[audioguru]

Years ago I bought a RadioCrap TV amplifier that was supposed to have a bandwidth from nearly DC to Green Light. It was garbage.
It was overloaded by all the not-very-strong signals.

I re-built it and then it worked perfectly.

 

[HiTech]

I've been through those cheapo little amps of various brands. The only ones that truly worked reliably were brands like Blonder Tongue, Jerrold, Wineguard, and Cecor. They also cost a whole lot more! My home currently has a Blonder Tongue amp, complete with switchable FM trap, slope, gain, and input attenuation, along with in and out test ports.

 

[Sceadwian]

You think this HD/Digital TV stuff is bad now? Wait a couple years. We're currently at one of if not the longest periods of times in recorded history with no solar flare activity.
SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Check that out for current solar activity.
In about 5 years we're going to be approaching a solar maximum that will be... interesting to say the least especially for currently max or overloaded electrical grids, let alone TV reception.

I'm not sure how far away you are from the TV stations you're actually trying to pick up (you can find out with TV maps) but mine are about 15 miles away, I live on the shielded side of a hill and I have no problems picking up every local broadcast using only a hacked together coaxial dipole indoors. You might want to make sure your cables and connectors are up to snuff, you could be losing a huge amount of signal just from bad wiring.

 

[gone2fly]

I am 40 miles from the majority of the channels I want to receive. Channel 5 is at 322 degrees, and channel 28 is at 321 degrees. I have a very good $30 boy scout compass that I am using to set the direction of my antenna. Channel 5 and 28 are the only channels I am having trouble with. There is 1 channel 65 miles away that comes in crystal clear all the time even with the 30 mph wind we have been having and even when the sun is on the horizon.

The wire I am using for the antenna to the TV is the wire that use to be on my DirecTV dish. It is about 40 ft long coax cable.

I checked all the connections and made sure they are tight with wrenches. I built the antenna strong as an army tank the bow tie part is 3/8" copper tubing. The tubing is all connected with #12 solid copper wire. All connections are soldered. The cable connector is mounted on a piece of angle iron to the antenna frame. The only part that can actually move from the wind is the screen and probably the #12 wire can wiggle a little bit. The screen is 1/4" hardware cloth from the hardware store it is not very ridged stuff so I built a frame around the outside edge to help hold it ridged.

I have 21 channels that all come in crystal clear all the time no matter what the wind is doing. Problem is channel 5 and 28-1 and 28-3. Signal is 97% about 50% of the time then it drops to 25% for a few seconds and the signal is lost until it returns to 97%.
All the other channels are 95% to 98% all the time.

 

[audioguru]

Is their a piece of building or something that is flapping in the wind between your antenna and the transmitting antenna?

There is a local FM radio station here. I drive pass their studio frequently.
But their transmitter is many miles away and it was moved. Their studio and me are "fringe".

 

[Mikebits]

Maybe tall tree's swaying in the path?

 

[gone2fly]

No flapping metal that I can see. The only thing in this neighbor hood is houses and trees. The trees have no leaves this time of the year. There is a school building 1 mile away and I am probably 100 ft above the roof of that building.

 

[blueroomelectronics]

Find out if you have coverage.
**broken link removed**

Also a DIY antenna might not work as well as a commercial version.

 

[gone2fly]

This is the link I have been using.

**broken link removed**