PDA

View Full Version : BUILDING A NOOA ANTENNA?



Pages : [1] 2 3 4

MikeinBaja
09-19-2011, 08:22 PM
I'm a satellite guy - not a radio guy - but I need to build an outdoor antenna for NOOA broadcast reception (162.400-162.550MHZ) for a weather warning station I recently acquired.

The existing unit has a telescoping antenna and an external antenna RCA type jack. If I take the unit outside about 35' away I can lock on with no problem - but no lock where the unit needs to sit inside (or anywhere else inside).

Any recommendations for sites? Google search wasn't much help. Dimensions? Material? Any hints?

HELP!

turbosat
09-19-2011, 11:09 PM
Mike, sounds like a simple 1/4 ground plane antenna would do the trick for you, if it works simply by going outside. If you can handle some easy soldering, you can build yourself one for probably less than 10 dollars, and stick it on a short mast on your roof or eave.
If you want ready made, you can buy one already built at the radioshack but they recently upped the price of theirs by about 8-9 dollars, its the 20-176, also called the sputnik by scanner fans. I've built a bunch of them and they work fine.
If you want to really get into antenna building, google for the plans for a super-j-pole, works great also.

edit: heres a link to one of many project pages covering home made ground plane antennas:
http://www.pbase.com/dickh/image/27104369
Use #12 wire, that 10guage stuff is too big to solder into the top of the SO-239 connector~!

turbosat
09-19-2011, 11:25 PM
Here's the link to the ready-built model :
Outdoor VHF-Hi/UHF Scanner Antenna - RadioShack.com (http://www.radioshack.com/product/index.jsp?productId=2103641)
And you can use RG6 to connect it, you'll need a couple of adapters to connect antenna to radio, a PL-259/RG6 from the antenna, and RG6-whatever on the radio end. And some coax-seal.

Pepper
09-20-2011, 11:13 AM
Google can't help if you search for the wrong thing. It's NOAA not NOOA.

MikeinBaja
09-20-2011, 11:49 AM
Mike, sounds like a simple 1/4 ground plane antenna would do the trick for you, if it works simply by going outside. If you can handle some easy soldering, you can build yourself one for probably less than 10 dollars, and stick it on a short mast on your roof or eave.
If you want ready made, you can buy one already built at the radioshack but they recently upped the price of theirs by about 8-9 dollars, its the 20-176, also called the sputnik by scanner fans. I've built a bunch of them and they work fine.
If you want to really get into antenna building, google for the plans for a super-j-pole, works great also.

edit: heres a link to one of many project pages covering home made ground plane antennas:
Ground Plane photo - Dick Harris photos at pbase.com (http://www.pbase.com/dickh/image/27104369)
Use #12 wire, that 10guage stuff is too big to solder into the top of the SO-239 connector~!

That looks intersting and doable. What length does each "arm" need to be?

MikeinBaja
09-20-2011, 11:50 AM
Google can't help if you search for the wrong thing. It's NOAA not NOOA.


Fat fingered it, but thanks for your helpful technical post.

Pepper
09-20-2011, 01:03 PM
Unfortunately that's as far as my technical knowledge goes on this particular subject. Since you did it twice I thought it just might be a legitimate case of not knowing what it was.

turbosat
09-20-2011, 02:02 PM
Here's a link to one of many online calculators:
BUILD A GROUND PLANE ANTENNA FOR 2 METERS AND MORE - SIMPLE AND EASY! (http://www.hamuniverse.com/2metergp.html)
Just put 162 mhz in the search box and it'll figure it for you. You can make them with coathangers too, but you need to sandpaper the ends where the bolts hold them onto the so239. I've made a bunch of them cut to the 108=136mhz aircraft band, If you need some pictures let me know, I'm in the middle of putting another one together right now. I use a 1 1/2" pvc pipe 'male adapter' to mount them in, fill in the spaces with hotglue to help weather proof, and a stub of 1 1/2" pvc to hold it to a mast.

MikeinBaja
09-20-2011, 05:48 PM
Here's a link to one of many online calculators:
BUILD A GROUND PLANE ANTENNA FOR 2 METERS AND MORE - SIMPLE AND EASY! (http://www.hamuniverse.com/2metergp.html)
Just put 162 mhz in the search box and it'll figure it for you. You can make them with coathangers too, but you need to sandpaper the ends where the bolts hold them onto the so239. I've made a bunch of them cut to the 108=136mhz aircraft band, If you need some pictures let me know, I'm in the middle of putting another one together right now. I use a 1 1/2" pvc pipe 'male adapter' to mount them in, fill in the spaces with hotglue to help weather proof, and a stub of 1 1/2" pvc to hold it to a mast.

I tried to download and the only thing that downloads is the images - no calculator. If yours is working, could you input 162MHZ and give me the lengths?

turbosat
09-20-2011, 06:27 PM
Sorry for the bum steer~! I forgot that that one is a downloadable program, for windows only, so I couldn't use it myself, forgot to delete it.
17 & 11/32" for the vertical, and just make the lower radials 2" longer. The lower ones aren't that critical on length, as long as they are longer than the vertical (they form the ground plane part of the antenna).
Just cut 'em close and it'll work fine, it'll have a good chunk of VHF spectrum covered.

edit: Here's one that works in java:
http://bfn.org/~bn589/antenna.html
click 1/4 button after inputting the freq...

Reigster at SatelliteGuys