Digital TV antenna interference

Does anyone have a solution to digital TV interference from passing motor vehicles? I have an amplified antenna that gets every local channel nicely, but every time a car or truck goes by the signal becomes scrambled until the vehicle passes. I’m lucky I don’t live on a busier block, but the traffic that I do have makes watching TV annoying.


Do you really need an amplified antenna?

If you live a long distance from the transmitter, you very well might. But I know too many people who live right in the city and get a strong signal that figure “more is better” and get an amplifier. An amplifier can overload the receiver and, more importantly in you case, amplify noise.

I just use a dipole antenna and I don’t have this problem. you could try blocking signals from the street or relocation the antenna.

As beowulff says, raising the antenna may be your only hope. The 8VSB modulation used by US digital TV is really sensitive to obstructions, reflections, and motion. it’s why there have been so few portable/mobile digital TV receivers.

most people use amplified antenna/antenna amps incorrectly. They’re meant for when you have a long cable run from the antenna to the receiver. They don’t really help in the case of poor reception, because they’ll amplify the noise as well as whatever weak signal they can get.

Yes I have a mohu leaf mounted on the wall at about street level. Any time a car (especially a van or box truck) drives by, we get noise on the picture (I assume the signal is bouncing off the large metal panels rolling by).

This. My daughter and son-in-law had the same problem with an indoor antenna mounted just above their TV. Moving it to near the top of the wall helped some. Putting it up in the attic almost completely eliminates the interference.

I have a non-amplified outdoor antenna that I mounted inside my attic. It gets perfect reception from broadcast antennas 25 miles away.

do you have it grounded? static electricity from a nearby lightning bolt has a nasty habit of finding antennas.

If you don’t want to remote mount antenna try a dipolemounted high on the wall. You will need a connector.

the bulk of US digital TV channels are up in the UHF band, between 470 and 690 MHz. a dipole meant for FM radio (87-107 MHz) would be sub-optimal.

meh. It’s 2 pieces of wire attached to a transformer meant for a TV. It’s a $6 solution.

Yes and that is a good point.

Years ago I had a tiny black and white TV that had rabbit ears antenna mounted on it. Even though the TV was inside and turned off, lightning would often blow a resister on it. My brother showed me how to solder in a new resister and I kept a supply on hand. He swore that it was from the antenna and not a spike in the electrical power.

it’s not “meant for a TV,” it’s meant for any device with an RF input expecting 75 ohm impedance. a twin-lead dipole is probably 300 ohms. at any rate, the transformer isn’t the important thing here, it’s the length and shape of the antenna elements.

You can argue why it’s not optimal all day long. yes, it’s a 300 ohm lead into an input expecting 75 ohm impedance. It cost $6. I get every local channel without interference from cars or internet math.

I suppose I could put a $150 antenna in the attic to achieve the same thing but I’m not seeing the logic.

The amplifier only makes up for a receiver that is going a bit deaf … its like a hearing aid.

The signal to noise ratio is your problem. Not enough signal strength, for noise.

Now, is the noise coming from the direction of the transmitter ???
If so, all you can do is go higher to get away from ground effect and the source of the noise.
If the noise is from another direction, then you can improve the signal to noise ratio … a better antenna… a more directional antenna… a higher antenna…

the world does not revolve around you. if you’re in a fringe area and reception is difficult, impedance mis-matches can be killer.

I was able to pick up a tower that was at least 35 miles away. Not sure why your attitude in this thread translates into the world revolving around me but I offered a $6 solution that’s easy to try and cheap if it fails. I have these antennas in different rooms on walls facing different directions feeding different TV’s.

I’ve tried the portable amplified antennas and unamplified models and combinations of the two with a splitter and this works for me.

But yowsers, thanks for explaining why It’s a waste of $6 to try something easy to set up before spending a lot of money and time on the roof of a house.