• Effective immediately we will be deleting, without notice, any negative threads or posts that deal with the use of encryption and streaming of scanner audio.

    We've noticed a huge increase in rants and negative posts that revolve around agencies going to encryption due to the broadcasting of scanner audio on the internet. It's now worn out and continues to be the same recycled rants. These rants hijack the threads and derail the conversation. They no longer have a place anywhere on this forum other than in the designated threads in the Rants forum in the Tavern.

    If you violate these guidelines your post will be deleted without notice and an infraction will be issued. We are not against discussion of this issue. You just need to do it in the right place. For example:
    https://forums.radioreference.com/rants/224104-official-thread-live-audio-feeds-scanners-wait-encryption.html

Gnarly background noise in feed stream

Status
Not open for further replies.
Joined
Feb 24, 2001
Messages
65,126
Location
Virginia
#1
This is super annoying - During scan when no audio is streaming via scanner I am hearing other scanner traffic. Yes, other peoples scanners. What's the deal? I have tried to cut out background noise locally but this insidious noise is well, insidious. Has the broadcastify server become so congested with feeds that in my dead space I, er we not get to hear our neighbor feeds? What can be done to stop this?

Win10
PS RadioFeed
C-Media External USB sound card Mic level 15
BCD325P2 Vol 5
AT&T 12Meg DSL
HP Ai1 PC (All internal recording devices off)
 

flythunderbird

Member
Premium Subscriber
Joined
Oct 1, 2012
Messages
957
Location
Grid square EM99fh
#2
I gave it a listen and can hear what you're talking about. Before we start pointing a finger at Broadcastify, let's try a few things.

Can you hear the background noise on your scanner with headphones?

Does your HP All-In-One have a line-level input? If so, try using that instead of the USB audio card and see if you notice a difference. It is possible that the USB audio interface is introducing noise into the audio signal. I once had a USB interface that was horribly noisy ... that interface was quickly replaced.

Have you tried a different audio cable between the scanner and the interface? Some cables are low quality and can introduce noise.

Using this free meter software:

Audio Level Meter

try to set your maximum volume level between -8 and -4 by turning up the scanner's volume and turning down the line-level or USB interface volume. This will reduce any noise being introduced by the computer (some computers are very noisy) and may show that the noise is being introduced by the scanner, the audio cable going to the interface, or by the interface itself. The All-In-One may be part of the problem itself, generating some of the noise internally, possibly from the screen backlight.

Can you try it on another computer altogether, one that is not an All-In-One?

Is your location in close proximity to towers? If you are close to a tower or towers, there may be some signals which are extremely hot and bleeding into the scanner (I once had this problem with a paging service, until the service adjusted its transmitter). Have you tried the scanner's global attenuator to see if that helps knock down the noise? If it does, then I'd suggest trying the attenuator on a channel-by-channel or trunking-site-by-trunking-site basis to see if it eliminates the noise. It may be that you'll have to try it on multiple frequencies to isolate and remove the noise.

Noise problems can be tough to track down. It may turn out that a number of small solutions will resolve the entire problem.

Please try these things and report back.
 
Last edited:
Joined
Mar 7, 2002
Messages
2,529
Location
New Orleans region
#3
Let me make a comment here for what irt's worth. Many scanners, radios and computers might have a DC voltage that is there all the time on the interface connection your using. If there is a DC voltage, it can cause audio problems.

Have you taken a volt meter and measured across the audio connections your using to see if there is any voltage? Have you measured between the chassis connection of your computer to the chassis of the scanner to see if there is a voltage? Have you measured the input audio connection of the computer to see if there is any voltage there?

This may seem rather basic, but if there is any voltage on any of the above measurements, you should be doing something to eliminate it. The simple way is to just put a capacitor in series with the high side of the audio connection. This will stop the DC voltage. I generally use just a simple 1.0 u.f capacitor in series with the high side of the audio connection. The exact value of the capacitor is not critical. The higher in value, the more the low audio tones, if I can use that statement, will be passed and the higher tones will be some what reduced.

Take a look at your scanner, radio or computer and see what you find.

One big note to remember is if your using a Motorola radio, they do not want either side of the audio connection grounded. You will clean out the audio driver and need to repair it. These radios are better off with an audio transformer to be used to couple the audio.
 
Status
Not open for further replies.
Top