Home |
Search |
Today's Posts |
#5
![]() |
|||
|
|||
![]()
Al Arduengo wrote in message ...
How would I best eliminate engine noise while listening to SW? I spend about 24 hrs a week on the interstate between Dallas and Austin and would love to be able to listen to SW. I rigged up my windup antenna by running it out the window of my truck and routing it around the bed back to the other side. The problem is that when using the external antenna I get very prominent engine noise unless the station I am listening to is quite strong. How would I (or can I) reduce or eliminate the noise? Is there an elegant way to implement a crude sw antenna on a vehicle? Clear Skies and 73, -Al I think the antenna and feedline, or should I say, lack of one, are the main problem. If I understand it correctly, you are running a random wire of sorts strung from the radio, and then around the bed of the truck. If you want to cut the noise, you need to mount an antenna that uses a well grounded mount, and is not coupling to the body of the truck. It's quite possible your MW antenna on the truck would be better than the wire being it has a grounded base. Or I assume anyway... What you really want, if you want top results, is a loaded whip much the same as a ham would run mobile. A hamstick "helically wound loaded whip" would be great as a mobile SWL antenna. You can buy them for each of the ham bands, and tuning and match for just receiving is not critical at all. So lets say you like 31m SW as an example...A 40, 30, or 20 meter hamstick would work fine. The 30 meter stick giving the best match. But the real secret is having a good well grounded base under the whip, and coax feeding the antenna. Being a ham, I have a 80-10 meter mobile antenna. "Works nearly all the HF bands". It's great for SWL, and noise is not a real problem. In fact, I get more noise generated from my tires at high speeds, than I do ignition noise. The hamsticks mount about the same as a helical CB antenna, and are cheap. Maybe 15-25 bucks apiece...Depends where you buy it...You want to keep the antenna itself as far away from the body of the truck as possible to avoid coupling to it. You really need a vertical whip to do that... MK |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Noise Figure Measurements | Homebrew | |||
signal to noise ratio drops on connecting the antenna | Homebrew | |||
signal to noise ratio drops on connecting the antenna | Homebrew | |||
Automatic RF noise cancellation and audio noise measurement | Homebrew | |||
CCIR Coefficients METHOD 6 REC533 // AUCKLAND --> SEATTLE | Shortwave |