2 Scanners / 1 Computer

I have 2 scanners plugged into my computer, one is hooked to a Line In and the other to Microphone. My problem is that I can hear the one connected to Line In bleed through the feed hooked to the microphone port. How do I get around this? I was thinking of getting 2 USB sound cards and use one for each feed. Will that fix my issue?

First of all, hooking a scanner to a microphone input is a really terrible idea. Audio quality is going to suck because the mic input is expecting a millivolt-level signal, and even if you use a line-out from the scanner, the signal is going to be about 1VRMS. You can attenuate it down to mic level, but then you're getting extra noise when you amplify the signal again with the mic input. Attenuating and then re-amplifying always increases noise level and degrades the signal. It's always better to use an input designed to match the output. Google "gain staging" for a more detailed explanation.

https://www.sweetwater.com/insync/gain-staging/
https://ledgernote.com/columns/studio-recording/gain-staging/

Using separate sound cards will better isolate the signals from the scanners, and should eliminate the cross-talk between feeds. Just make sure both have line-level inputs.

Agree with Jon 100%. Using the Mic for a scanner feed or other listening purposes should be a "last resort". Always better to use Line-In from the PC sound card and/or a separate USB sound card. Several good choices for those on the market.

Would something like this work?

https://www.amazon.com/Sabrent-Exte...coding=UTF8&psc=1&refRID=2E6CR71Y8MH398N3YPHF

No. It only has headphone out and mic in jacks.

Give me an example of something that will work, please. Everything I Google has a headphone jack and not a line in.

I use these for my Pi3b's. Should work fine on a Windows PC as well. I've heard of some people having issues with Linux, so if you"re running a distro, best to do some research first. Otherwise, I've had good luck with them.

https://www.ebay.com/p/HDE-A14-5-1-Channel-USB-External-Sound-Card/1400167209?iid=361502397040

* Note: My link is just to a random re-seller....I am not particularly endorsing them ....

I have two of these connected to my PC for scanner feeds that I currently run on Radio Reference:

https://www.bhphotovideo.com/bnh/co...h1OeQr4EAYYAiABEgLmf_D_BwE&is=REG&sku=1138017

NYRHKY94 said:

I have two of these connected to my PC for scanner feeds that I currently run on Radio Reference:

https://www.bhphotovideo.com/bnh/co...h1OeQr4EAYYAiABEgLmf_D_BwE&is=REG&sku=1138017

Click to expand...

Thanks for the recommendation!

I can recommend a proper audio mixer that can serve as audio interface. Take a look at one of the Behringer mixers. One that has USB connection should work very well.

These work just fine for a few bucks from E-Bay....Get a few...I bought 5...Its plugged into the Mic.....Works fine.....Listen to my feed....
..A 396T on a laptop with a USB sound card...With Tags....Also try RadioFeed....Scannercast hasn't been updated in 8 yrs

javidnky2005 said:

Would something like this work?

https://www.amazon.com/Sabrent-Exte...coding=UTF8&psc=1&refRID=2E6CR71Y8MH398N3YPHF

Click to expand...

Didn't say anything about working on Win 10....Mine posted does work on W10

rcool101 said:

View attachment 62206
These work just fine for a few bucks from E-Bay....Get a few...I bought 5...Its plugged into the Mic.....Works fine.....Listen to my feed....

Click to expand...

And your feed audio is unnecessarily noisy as a direct result. Attenuating a signal down to mic level and then reamplifying always degrades audio quality.