...in many respects, we've our work "cut out for us"...

NOAA ALL HAZARDS Weather Radio transmitters operate with power from 100 to 1000 watts, with a reception range of 'city blocks' to 40 miles if everything is perfect. It often isn't for our location, hardware budget, etc. The frequency used is between Standard VHF television channels 6 and 7...and is narrow band FM with a maximum frequency deviation of 5 kHz.


Stream Quality

...is so important, that several PWS team members audit the site consistently for quality and offline streams. We show you any last update times, and 'flag' any streams with issues, giving both users and providers the last observed streams status, or any station listing updates.

files update

Important Note:

Once Online, Stuff will happen. The Feed Is Dead. Long Live the Feed. Useful info and utilities at:
STREAM RELIABILITY  —  Is my stream Online or NOT? — Some monitoring utilities and info


marginal quality

Stream Quality

 — excepting a fault in a NWR transmitter —  this is the responsibility of each provider.
A daily, quick, online check of your stream will prevent many 'dead' or 'disabled' feeds.



Below, see a 'quality grid' with actual NWR streams, recorded Live in July 2017.

For simplicity, and because the "BUTT" encoder is cross platform, is free, and most anyone can fire it up, we used it as our 'VU' application. The streams were monitored as PC audio directly from the NOAA Weather Radio Org main index stream player. Volume Level reference set for "optimum -4 ref" on "BUTT" using the online 'reference' track, "Look Out For Flying Pigs". (Audio compression standards are expected around 89% peak -- Pigs is encoded at 90%, and 'compares' with about a -6 to -3 db reference, depending on content.)

Additionally, as NWROrg develops 'Quality Standard' and evaluation, at the very end of the 'Station Player' list, there are Constant Level Sweep Audio references used in the quality eval for many parameters... the sweeps cover the bandwidth expected for the NOAA transmission.


Assuming we've turned on our receiver, got some NWR audio through its loudspeaker... let's enable our encoder lashup, whatever it may be, and plug it into the output jack of the receiver..., ...then we may be confronted with one or more of the below 'grid row cells':




Hover thumbnail to play examples

60 Hertz Line HUM Painful to Marginal Often simply a bad audio cable. how help

Very Poor Signal Poor Signal & 1 Channel Solved how help

Aliasing 8 kHz Aliasing 16 kHz Solved how help

Low Volume Low Volume & 1 Channel BAD EXPERIENCE how help

Low Minimum High Maximum Optimum how help
Last Resort Level Setting: Match your online stream level to the same 'ear level' as the reference track 1 on the web page player: "Look Out For Flying Pigs"

That Annoying 60 Hz (or other) Audio Junk

First, it would appear that some very, very low Line Freq Hum and Other Noise artifacts are common in many streams, and there can be many causes. First, most of us are 'piggybacking' the stream onto devices we likely use for other things, providing NOAA Weather Radio streams as volunteers, aren't professionals, and labor under individual constraints and limitations, Additionally, some esoteric junk can be inherent in a streaming platform's Sound Card limitations! Extremely low hum and noise, distortion, can be acceptable, in fact, expected. But...

GROUND LOOP
A ground loop typically occurs when two or more pieces of equipment are plugged into different AC outlets, then connected together by signal cables— whose shielding is connected to ground. A less-common but similar effect is possible when a device is 'isolated' but connected to a device that 'isn't", or vice versa, especially when 'grounding' is attempted on the Isolated Device... which can also prove hazardous to life, limb and property. Some strange stuff can occur when two 'isolated' devices are interconnected, also! Wall Wart power devices are, in effect, 'isolators' for example.

A Ground Loop can create a "virtual antenna" that grabs anything that may be floating around, especially Power Line EMI, and other 'near field' energy components.

A SHIELDED LAN RJ45 cable from streaming device to router can sometimes induce a Ground Loop! Try an unshielded patch.

A fancy extra SHIELDED audio cable from receiver to streaming device could be a sneaky villian.

Anything that breaks the loop will kill the noise. Some folks use 'audio cable' noise suppressors, which are basically isolation transformers — in many cases this simply relieves a symptom, without resolving the cause ...yet they can be effective, and a "quick'n'easy fix" in some situations.



Let's get rid of ANY hum / noise if possible!


ANTENNA / RECEIVER LOCATION
Mains AC Power induced /related Hum or Other Noise

Stray EMI in the environment, the receiver thinks it's a radio signal. And if the NWR signal is already 'weak' the noise can appear enhanced.

Relocate the Receiver / Antenna .. a meter in any dimension can make a huge difference, especially height / altitude.

Using the receiver's built in Rod antenna? Try an external antenna option.

Using an External Antenna? Make sure the Coax is good, connections are good, and the antenna isn't near your power distribution panel, etc.



CABLES — AUDIO / Plug Adapters
Poor, or loose shielding, poor or high resistance can induce all manner of evil.

Believe it or not, even physical vibration noise from cord movement!



CABLES — POWER
Never run a power cable across or near the audio signal cable, the receiver or its antenna, or the external antenna's cable!

If have hum and it isn't a ground loop, this could be a sneaky snake.



CABLES — USB
Use cables with ferrite suppressors, or clamp on ferrite beads.

Same rules as apply to Power Cords. Don't run USB cable near your audio signal cable, etc.

If you use USB cable as your 'audio signal cable', especially with adapters for audio, apply the same logic as for Audio cables.



DEVICES
Locate your receiver and route its cables, antenna etc as far as possible from any stuff that emits RF, or other EMI.

Even a meter can make a difference!



RECEIVER
WHOA... been known to have issues!

Bad Wall Wart supplies, bad audio out jacks, bad shielding....



WEIRD THINGS
Here are some real sneakies:

Receiver/antenna is on or very near a Metal Shelf, especially if it's of magnetic material or has magnetic material supports.

Receiver/antenna is near an external wall that's insulated with 'aluminum' clad, or similar, foam panels.

Receiver/antenna / streaming device / cable / power cord is near a "Power Strip" with lots of Wall Warts, and / or plugged into an older 'strip' that uses a Neon Bulb power indicator -- especially if said indicator 'flickers', junk it! Junk it anyway.. just on suspicion. or at least remove the bulb circuitry. Very Sneaky.

A Power Strip somewhere nearby or on the same AC circuit has a bad 'On/Off' switch, or outlet, that's become a spark gap transmitter. (Marconi worked for years to achieve this) Ditto for home wiring distribution... arcing breaker in Mains Panel, even...

And here's a REALLY NASTY Super Sneaky:

A "Power Strip" or other device has a surge / lightning protector of certain types. It has been damaged ... and as we sigh with relief, having survived the last Power Utility event, or thunderstorm, that power strip has now become an ELF/VLF transmitter, and Submarines are lost at sea because ELF/VLF COMM is jammed.

Then you have the 'run of the mill' junk creators: Light dimmers, Security Lights, Neighbor's Smart Meter or Television, etc, etc.

TRUE... some of the above are extremely rare, especially with the signal we're after.
... But, if you've tried everything else...???