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Weather Station Hardware => Weather Radios => Topic started by: AIW on September 25, 2015, 11:29:12 AM

Title: NOAA Weather Radio Design Inputs
Post by: AIW on September 25, 2015, 11:29:12 AM
From looking through all of the WX Radio discussions I see that there are numerous items that most users of NWR do and do not like about the current radios on the market.

I am going to be designing a new NOAA Weather Radio from the ground up and so through the end of October, I would like to take any and all inputs any of you might have as to features you would like to see. I know everyone has different preferences, but there are always ways to make certain options selectable. Many times I have even found that it is easy to build a listing of options in a text file that is specific to the user and then the the radio would load those options each time it was turned on. This is especially good for pairing event and fips code pairs without having to step through 100 menu settings on the radio screen.

A little info the the basis of the design.....

-I have not decided on the micro I will use yet, but the receiver will be based on the Silicon Labs Si4707. I've been selling a breakout board for this chip for a couple of years now for the DIY community and it is a very stable product. -I have also recently been working on an additional low noise amplifier for the front end so that areas of weak reception get a bit of a boost.
  ** I have a friend testing a new board I'm making for the Raspberry Pi2 that has the LNA on it and he went from getting one station (barely) in only one room of his house to 3 stations anywhere in the house.
-I would like to have WiFi capability in order to pull CAPS data for since CAPS alerts will generally have polygon information to narrow down the actual alert to your physical location vice the entire county code.
**This might also enable ability to send out email and text alerts to users from the radio.
-To keep costs down there probably won't be touch screens or anything too extravagant, but you never know.
-I'm also sensitive to the fact that most people also don't want to pay a significant amount of money for the unit either so I'll have to keep that in mind when putting all the suggestions together.

So....if you feel inclined to provide your input, please do so. Everything from built in speaker, external speakers, line-out audio, buttons, usb control, leds, relay outputs, you name it...

Thanks!!
Title: Re: NOAA Weather Radio Design Inputs
Post by: Cutty Sark Sailor on September 25, 2015, 12:33:48 PM
Build a streaming server into it, as an option perhaps!  Audio out jacks, mono channel split, .. not single channel/mono.
Title: Re: NOAA Weather Radio Design Inputs
Post by: AIW on September 25, 2015, 02:33:06 PM
Even though NWR is mono the Si4707 has both a left and right mono channel built in. So both left and right could be connected 3.5mm stereo audio output jack to enable a normal stereo cable instead of needing to "Y" it off with a special cable.
Title: Re: NOAA Weather Radio Design Inputs
Post by: Cutty Sark Sailor on September 25, 2015, 03:56:51 PM
Even though NWR is mono the Si4707 has both a left and right mono channel built in. So both left and right could be connected 3.5mm stereo audio output jack to enable a normal stereo cable instead of needing to "Y" it off with a special cable.
Righto.. but I wasn't aware.. takes care of it. 
Title: Re: NOAA Weather Radio Design Inputs
Post by: vreihen on September 25, 2015, 05:48:40 PM
I don't exactly know how you can solve the problem with NWS radios that we have locally.  I live near the service border of three different NWS offices.  The only solid NWS radio coverage that I receive comes from a neighboring office, and I don't think that they are doing a courtesy alert for people on our side of the line.  Most people tune in the strongest (only) NWS signal, not knowing the politics that they probably won't receive a weather alert unless the storm is coming from the other side of the line. 

Oh, and it bears mentioning that NYC is my local NWS office, and I'm not in the middle of farmlands in Nebraska with minimal population density.....
Title: Re: NOAA Weather Radio Design Inputs
Post by: AIW on September 25, 2015, 06:12:27 PM
vreihen,
Not sure if the gain realized with the front end amplifier will allow you to receive the proper frequency or not. You might be a good site for me to measure the increased signal reception to see if it helps you out.

Sounds like storms that typically head your way are serviced by the transmitter installation with the poorest signal. The system NWS uses to generate the messages is in the process of changing, but I'm not aware of any major changes that may affect which transmitters get que'd up for alerts. I think that will still be dictated by projected storm track.
Title: Re: NOAA Weather Radio Design Inputs
Post by: AIW on September 25, 2015, 06:14:21 PM
....with the addition of wifi, I should be able to pull CAPS data so that even if you still have NWR reception issues we could alert you based on the CAPS feed.
Title: Re: NOAA Weather Radio Design Inputs
Post by: vreihen on September 26, 2015, 07:37:04 AM
Not sure if the gain realized with the front end amplifier will allow you to receive the proper frequency or not. You might be a good site for me to measure the increased signal reception to see if it helps you out.

I cannot receive the radio signal from the NYC NWS office from my truck with a 5/8 wave 2-meter antenna, nor can we receive television signals from NYC due to the terrain.  The NYC NWS office doesn't even claim to cover our area by radio:

(http://www.erh.noaa.gov/okx/nwr/KWO35.gif)

I live in extreme northern Orange County, just to the east of the Sullivan/Ulster border point.  Sullivan is served by NWS Binghamton, and Ulster is served by NWS Albany.  The Albany office has a transmitter (WXL37) about 15 miles north of my in Ulster County, which gives a strong (and only) NWS signal:

(http://www.nws.noaa.gov/nwr/Maps/GIF/states/newyork-e.gif)

This map shows us as covered by NWS radio...but fails to mention that it is by the wrong forecast office!  As I said earlier, I'm not 100% sure that Albany isn't re-broadcasting alerts for NYC on the nearby transmitter as a courtesy, but I doubt it.  I personally have Weather Underground alert subscriptions sent to my smartphone, which sees to be the only thing that WU can do right any more.

Radio or not, the politics get interesting for something as simple as a weather forecast when you have three different offices issuing their own different prognostications...especially in the winter.  One office will be predicting 6+ inches of snow have have a winter storm warning up, while the other office is only predicting flurries (or rain) and doesn't put out any type of notice at all.  It's almost comical to think that neighbors on opposite sides of the imaginary line could see such different weather from the same storm.  :grin:

TWC's local alerts are interesting as well, since the local cable franchise serves all three areas from the same head end.  When t-storms are rolling in from the northwest, the flood alerts from where the storms already have been (Binghamton office) interrupt the warnings for the approaching storm in our area.

Anyway, as long as your radio has an Internet feed that can cope with these silly imaginary lines, I think that it would be useful to the citizens of our area.....
Title: Re: NOAA Weather Radio Design Inputs
Post by: vreihen on September 26, 2015, 07:46:30 AM
I stand corrected.  According to this page, the local Albany office transmitter (WXL37) is sending SAME messages for Orange County:

(http://www.nws.noaa.gov/nwr/coverage/site2.php?State=NY&Site=WXL37)
Title: Re: NOAA Weather Radio Design Inputs
Post by: jimform2k1 on November 06, 2015, 08:06:07 AM
How about the ability to monitor/scan more than one channel for alerts.


From looking through all of the WX Radio discussions I see that there are numerous items that most users of NWR do and do not like about the current radios on the market.

I am going to be designing a new NOAA Weather Radio from the ground up and so through the end of October, I would like to take any and all inputs any of you might have as to features you would like to see. I know everyone has different preferences, but there are always ways to make certain options selectable. Many times I have even found that it is easy to build a listing of options in a text file that is specific to the user and then the the radio would load those options each time it was turned on. This is especially good for pairing event and fips code pairs without having to step through 100 menu settings on the radio screen.

A little info the the basis of the design.....

-I have not decided on the micro I will use yet, but the receiver will be based on the Silicon Labs Si4707. I've been selling a breakout board for this chip for a couple of years now for the DIY community and it is a very stable product. -I have also recently been working on an additional low noise amplifier for the front end so that areas of weak reception get a bit of a boost.
  ** I have a friend testing a new board I'm making for the Raspberry Pi2 that has the LNA on it and he went from getting one station (barely) in only one room of his house to 3 stations anywhere in the house.
-I would like to have WiFi capability in order to pull CAPS data for since CAPS alerts will generally have polygon information to narrow down the actual alert to your physical location vice the entire county code.
**This might also enable ability to send out email and text alerts to users from the radio.
-To keep costs down there probably won't be touch screens or anything too extravagant, but you never know.
-I'm also sensitive to the fact that most people also don't want to pay a significant amount of money for the unit either so I'll have to keep that in mind when putting all the suggestions together.

So....if you feel inclined to provide your input, please do so. Everything from built in speaker, external speakers, line-out audio, buttons, usb control, leds, relay outputs, you name it...

Thanks!!
Title: Re: NOAA Weather Radio Design Inputs
Post by: 92merc on November 06, 2015, 09:07:11 AM
For me, I'd also like a streaming server to stream it out to the web.  I have decent coverage in my area with SAME signals.  But all I want is to be able to embed the stream onto my webpage.  If that could be done with a RPI and keep it off my weather PC, even better.
Title: Re: NOAA Weather Radio Design Inputs
Post by: AIW on November 06, 2015, 04:27:19 PM
jimform2k1

Ability to scan for best channel would be available, but to continuously scan for alerts on all channels may cause you to be off of frequency that sends one out while scanning others. Only way I see this as a valid possibility would be to have multiple receiver chips to monitor multiple frequencies simultaneously....unless you have another idea.I'm all ears.

92Merc

I actually have a Pi B+/v2 based NWR SAME board that should be ready for purchase after first of the year. It will have a built in front end LNA, onboard 8 ohm speaker and a line out jack, and two 5A relays that are GPIO controlled (configurable as NC or NO). The line out could be routed back to a USB audio device for streaming.
Title: Re: NOAA Weather Radio Design Inputs
Post by: AIW on December 03, 2015, 08:23:10 AM
Sorry for the lack of input on my part for this topic. I've been finishing up the Pi B+/2 board and am dropping it off at the assembly house today so hopefully those will be available first part of the New Year.

.......for the radio project I believe what I will do is make something that works as received and has plenty of features, but at the same time give those with good programming skills the ability to expand it as they wish without hardware changes. I'm a big fan of the Pi, but I think it really excels in the networking, database, linux pc side of things. I like offloading monitoring and control of hardware to a stand alone micro and then interface the two. So I have some ideas but don't want to let the cat out of the bag till I have something viable.

I'll get working on this and provide feedback as I have it.
Title: Re: NOAA Weather Radio Design Inputs
Post by: AIW on January 26, 2016, 02:56:18 PM
Still looking into the options here but the Raspberry Pi B+/2 NWR interface boards are up on Tindie for anyone interested in building their own weather radio setup.

https://www.tindie.com/products/yniibi96/raspberry-pi-noaa-weather-receiver-same-decoder/

I'm not a Pi "guru" but for those who are you should be able to route the 3.5mm audio back to a USB audio dongle and make a streaming NWR server using the Pi.

More to follow on the stand alone radio as I have it to provide.
Title: Re: NOAA Weather Radio Design Inputs
Post by: W Thomas on February 09, 2016, 03:27:16 PM
I have been AWOL here for a while due to health and other issues so I'm just now reading your post. Kudos for wanting to build a better NWR receiver! I live in a convergence zone for NWR here plus a bunch of adjacent channel intermod causing paging transmitters. So if there are others in the same boat might I suggest looking into making this a tight as possible front end?providing the chip used will allow modifications. MY web server feed is currently down due to a damaged antenna but in the end I had to use a Kenwood TK280 Portable programmed to Narrow band and one band pass cavity to get a usable product.

Anyway it's great you are interesting and willing to look at the possibility of a better receiver!   I'll be watching this carefully :)  Very interesting !
Title: Re: NOAA Weather Radio Design Inputs
Post by: AIW on February 11, 2016, 03:18:28 PM
I'm currently working on the prototype portion of the dual receiver part of the radio. This will utilize a bandpass filter that will feed the same LNA feature as my Raspberry Pi receiver board has implemented on it. After front end amplification it will go through an RF splitter to feed 2 separate Si4707 chips. This will allow those in areas of dual transmitter coverage to tune into both frequencies for monitoring of alerts. The base receiver board will provide both left and right audio for both chips, as well as, interrupts from each so that the processor will know which receiver section the alerts have been received on and pending processing.

How the audio gets broken out for the user is TBD. Since NWR is mono, but the Si4707 will put the audio on both channels it may make sense to route one side of both receivers to a speaker with a selector switch and then route L/R of both receivers to 3.5mm jacks on the rear for external monitoring as the user sees fit (PC speakers, audio feed to streaming server, etc). Those details can be hammered out later after I get the dual receiver functional.

Picture of initial proto is attached. All the parts aren't even on it yet, but thought I would show that I'm actually working towards the goal  :-) ....The dotted copper square is a place to solder an EMI shield to. I'll be doing some testing to see if the SNR performance is increased by adding a shield over the top of the receivers to keep out excessive noise.

Title: Re: NOAA Weather Radio Design Inputs
Post by: W Thomas on February 11, 2016, 09:01:40 PM
Excellent idea! I am in one of those split areas with the estimated receive level being close to equal. I have monitored both and when our county is alerted the farthest transmitter from me seems to get the quicker routing resulting in alerting first.
Nice design on the project  =D>