NOAA antenna ideas, and Polarization?

[eahuntley]

I'm not sure if this should be posted here or not; If it belongs somewhere else, please let me know.

I need to build an antenna for my Oregon Scientific WR606. I'm pretty sure the antenna would be vertically polarized, but I haven't been able to find anything verifying that. Can anyone say for certain?

Has anyone made an antenna for NOAA reception? Any suggestions on what type of antenna works best?

For some reason this radio has an RCA jack for the external antenna jack, but I've yet to see an antenna with an RCA connector.

 

[K9WG]

Vertical polarized

How far are you from the transmitter? A simple 1/4 wave ground plane might be adequate.

http://www.qsl.net/wrav/2mground.htm

 

[WA1ATA]

Start with the simplest --- a few inches of wire on an RCA plug.

#2. 17 1/3" -- that's a 1/4 wavelength for the 162.55MHz station in the Portland area.
http://www.nws.noaa.gov/nwr/Maps/PHP/site.php?State=OR&Site=KIG98

#3 Add the ground plane radials as in the link given by K9WG -- except because of the higher frequency the vertical whip should be 17-1/3" and the radials 18-1/8 ". If you have had to go this this antenna, then you will probably be mounting it outside.

Since there is a local station in Portland, I'm betting that the simplest antenna will work ---- a few inches of wire hanging off the back of your receiver.

 

[eahuntley]

I just looked it up, and I'm 39.5 miles away from the 330W transmitter. I haven't been able to find the height of the tower though.

I'll see if I can find an RCA connector, and attach the 17 1/3" of wire to it. I've got 14g and 18g wire, both insulated. should either of those work OK?

I don't have any problem putting an antenna outdoors, if that's what I have to do. I've already got a couple verticals out there, and am working on a double crossed dipole for ATP satellite stuff.

Vertical polarized

How far are you from the transmitter? A simple 1/4 wave ground plane might be adequate.

2 meter 1/4 wave Ground Plane


Start with the simplest --- a few inches of wire on an RCA plug.

#2. 17 1/3" -- that's a 1/4 wavelength for the 162.55MHz station in the Portland area.
NOAA Weather Radio KIG98

#3 Add the ground plane radials as in the link given by K9WG -- except because of the higher frequency the vertical whip should be 17-1/3" and the radials 18-1/8 ". If you have had to go this this antenna, then you will probably be mounting it outside.

Since there is a local station in Portland, I'm betting that the simplest antenna will work ---- a few inches of wire hanging off the back of your receiver.

 

[WA1ATA]

I'll see if I can find an RCA connector, and attach the 17 1/3" of wire to it. I've got 14g and 18g wire, both insulated. should either of those work OK?

Either 14 or 18 gauge wire will work, provided the 14 gauge wire can fit inside the center pin of the jack.

I'm 39.5 miles away from the 330W transmitter. I haven't been able to find the height of the tower though.

It's not the height of the transmitter station that counts, it's the hills and buildings in between you and it that cause problems.

My best antenna for weather radio is a twinlead J-pole that I cut for the 156.3 to 157.1 marine band.
Like the 2 meter FLEXIBLE J POLE ANTENNA , but scaled down in size proportionately. With that antenna and the multiple stations in the SF Bay / Monterey area, I receive strong signals on 6 out of the 7 weather channels.

 

[eahuntley]

Yeah I've got one of those (cut for the 70cm band) in my emergency kit, and I've always been happy with it. I'm pretty sure I've got some 300ohm twin-lead around here somewhere, and I know I've got some RG-58. That should work, right? The J-pole I have was made with that black foam insulated twin-lead that's a real pain to cut. The stuff I have is of the clearish variety that looks similar to the stuff most broadcast FM dipoles are made of.

Either 14 or 18 gauge wire will work, provided the 14 gauge wire can fit inside the center pin of the jack.

It's not the height of the transmitter station that counts, it's the hills and buildings in between you and it that cause problems.

My best antenna for weather radio is a twinlead J-pole that I cut for the 156.3 to 157.1 marine band.
Like the 2 meter FLEXIBLE J POLE ANTENNA , but scaled down in size proportionately. With that antenna and the multiple stations in the SF Bay / Monterey area, I receive strong signals on 6 out of the 7 weather channels.

 

[bryan_herbert]

You can also just buy a Female BNC to Phono Plug adapter and use any scanner antenna.

BNC Female to Phono Plug Adapter - RadioShack.com

 

[n5ims]

If you go with an outside antenna, you may want to use some RG-6 or RG-6 Quad Shield cable. They make RCA compression connectors for either type that is used in high-end AV work so you'll get a good connection. Make your antenna using a chassis mount F connector that has the 4 mounting screws and put a compression F connector on that end (and some silicon seal on the antenna base) and you should be good.

 

[K9WG]

... snip ...

I'll see if I can find an RCA connector, and attach the 17 1/3" of wire to it. I've got 14g and 18g wire, both insulated. should either of those work OK?

... snip ...

For what you will be using this for, the gauge of the wire does not matter.

Also if you are just going for a simple wire out the back find an old stereo cable with the RCA connector already on it and just strip away the shielding. No soldering required.

I have found with NOAA broadcasts you don't need much of an antenna unless you are really far away from the transmitter, so i wouldn't be too concerned about length.

eta: I can hear Indy NOAA full strength with a back of set 800MHz antenna and I am a good 25+ miles from the transmitter

 

[jim202]

Why don't you bite the bullet and modify the radio to have a standard coax connector. You could probably just replace the RCA with a BNC chassis connector and not have to do any drilling. Now with the BNC on the radio, you have something standard to work with. You don't have to play around with finding a rare adapter or clueging together some sort of adapter to take normal coax cable.

If you go to the NOAA site, you should be able to find the coverage map for your region and see the predicted coverage for the transmitter in question. The whole country is there, so you will have to pick the state and region to find the transmitter in question.

Being a ham radio operator, you should know where to go to obtain all sorts of ideas on different antennas. I find that the internet is a wealth of info with a simple search request. The info and feedback on here is not always the greatest source from people that haven't been working in the field of radios for any great time. Having been in the service and engineering area of public safety radio systems for well over 45 years now, some of the suggestions I see are down and out funny.

 

[eahuntley]

Being a ham radio operator, you should know where to go to obtain all sorts of ideas on different antennas. I find that the internet is a wealth of info with a simple search request. The info and feedback on here is not always the greatest source from people that haven't been working in the field of radios for any great time. Having been in the service and engineering area of public safety radio systems for well over 45 years now, some of the suggestions I see are down and out funny.

Yeah, I've got book after book of antenna designs. I was mostly just looking to find out what experiences people have had with different types of antennas for this specific application. My immediate instinct was to just build a j-pole or a di-pole and mount it outside, but I've since talked to several people who say they get good results with just a random wire inside the house.

For starters I found an AV cable of some sort(40", RCA on each end) and just plugged that into the unit. On Wednesday I picked up the test flawlessly, so it seems to have worked. I bought this radio at a local electronics surplus store, and I wasn't even sure it worked. Now that I know it works maybe I'll make a more precise antenna. I might just cut a wire to the proper length and use that.

I've been thinking about trying to swap out the RCA with a BNC, or maybe even an SMA. I have no idea why they would have used it in the first place. Oregon Scientific doesn't even sell an RCA antenna(that I could find) to use with it. Now that I know it all works I'll get a bit more serious about swapping it. I already have plenty of BNC & SMA antennas, and it would be nice to be able to use them.