• 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

Two Questions.

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sm3000

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Ok. Forgive me if this is posted elsewhere. I have a question. If the answer is actually posted somewhere on RR, please let me know via a link and I'll go read it...I couldn't find it for the life of me.

What's a discriminator tap? I see people talking about them on here, and I decided to go to the Wiki, but it didn't quite explain it to me ... I just saw pictures n stuff, but no real "description" of what it does.

And secondly, what benefits are there to having a 'tap' on your scanner?

Just curious. :)
 

Saint

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Tap

sm3000 said:
Ok. Forgive me if this is posted elsewhere. I have a question. If the answer is actually posted somewhere on RR, please let me know via a link and I'll go read it...I couldn't find it for the life of me.

What's a discriminator tap? I see people talking about them on here, and I decided to go to the Wiki, but it didn't quite explain it to me ... I just saw pictures n stuff, but no real "description" of what it does.

And secondly, what benefits are there to having a 'tap' on your scanner?

Just curious. :)
This may be of some felp to you.
http://wiki.radioreference.com/index.php/Discriminator_output
Steve
 

exkalibur

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A discriminator tap allows you to get baseband audio. In a radio, received audio goes through some filtering to remove all the junk outside of the pass band - on real radios this also filters out PL/DPL tones. However, most types of data use audio frequencies that fall outside of the passband, or are otherwise molested by the filtering. If you are trying to decode said data, having it filtered out/molested by the filter in the radio, you aren't going to have favourable results.

However, tapping the audio BEFORE the filter (IE, direct from the discrimiator), bypasses any of this allowing you to get exactly what is received.

Unless you plan on running software to decode data transmitted over the air, such as ACARS, ATCS, POCSAG, Control Channel data, etc... - there's no benifit to the average user.
 

mikewazowski

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exkalibur said:
Unless you plan on running software to decode data transmitted over the air, such as ACARS,
ACARS is AM and doesn't require a discriminator tap since the discriminator is not involved.

Use your headphone jack and you'll be fine.
 
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