cb/scanner antenea???

"Understood...however when do NOAA radios like mine "transmit"? "

The antenna dosn't care if you are transmiting or receiving if it would stink as a transmit antenna it will also stink as a receive one .....

 

My Yaesu VX-170 2m HT can pick up 4 weather stations. 2 of them about 100 miles away.

 

Cordless phones are also a no listen under federal law.Not all unscrambled signals are legal to listen to, studio to tranmitter links are illegal to list to yet I have QSL's confirming reception of some.

 

I know it was here in Florida and checked your right there is also a federal law.

Anyone modifing a scanner to cover cell-phones is asking for trouble also with most systems going digital it may no longer work .....

 

Needless to say no range distance is set in concrete. There are many factors in determining the effective range.

Secondly most weather station receivers don't have the receiving sensitivity that most ham receivers have. That would be like comparing your receiver to my old Heathkit Lunch Box.

As the OP said: "However as of last week the radio didn't go off at all when our county was placed under a tornado warning...thankfully we had the TV on...of course then I pushed the radio button and it was then confirmed...when the NOAA station sends out the alarm signal, the radio turns on automatically all by itself. "

Leon
(kc0iv)

 

And WHAT is wrong with a HW-29 or HW-30 ?

My goodness I worked many states on both of them in the mid to late 60's

My station has been updated since them but i still have a warm spot for the lunchboxes .....

 

Nothing WRONG with the old lunchbox but you have to admit their receivers were no where near what a modern receiver is. As an example the Heathkit HW-30 had a sensitivity of 1.0 micro volt. While a Icom IC-V80/E has a sensitivity of 0.14µV.

Leon
(kc0iv)

 

Your talking FM VER AM ....

I have seen heathkits modded with converters down to 10 meters and the receiver modded to a 10 meter one from 2 meters that was below .5 uv not bad for the days of 3DB NF devices.

I remember modding a SCR-522 and revamping the 12 mhz IF into one stage high and a mixer and one stage at about 1.5 mhz and adding a nuvista preamp in front of that gosh it work good ....

Also we ran beams in those days not omidirectional verticals .....

BUT you could do that then try doing that on a SMT board .....

 

FM vs AM has nothing to do with receiver sensitivity.

As far as beams. I've had several in my day. The largest was a 4 x 20 element 2 meter array. A 4 element 20, 15, 10 meter beam was used on the lower bands. BTW ice storm took the quad down.

The house we live in now won't support the big arrays so I have a 50 foot windmill tower with a 4 element 20, 15, 10 meter beam and a pair of 12 element 2 meter antennas. I have a 80/40 dipole for those bands.

We are getting way off topic so I'll end it.

Leon
(kc0iv)

 

Final comment ..... somethings apply on VHF no matter what your lissing to.

I have built AM receivers below .25 UV but it takes lots of work and very low noise devices.

The noisefloor of a receiver is first stage NF and bandwidth The low noise transistors ( under 1 db noise ) common if FM radios today were not around 40 years ago in the days of AM. Common NF on 2 in the 60's was as high as 10DB.

I work in 2 way radio on UHF systems our work units run about .25 UV.

My station here on 2 meters has a 20db gain .5dbNF gasfet preamp that takes it down on FM to under .1uv even less on SSB.

I run a net on 144.210 sundays at 9pm Eastern time There is a very good FM net in grid square EL-87 at 8pm on 147.550

If someone wants that weather radio to work right start likw we do on 2 meters with a good antenna.

Bruce
144.210
146.520