Actions

Difference between revisions of "Discriminator output"

From The RadioReference Wiki

 
(74 intermediate revisions by 14 users not shown)
Line 1: Line 1:
The Discriminator output from a scanner is the raw, unfiltered signal that a scanner produces before it is sent to the audio stage for output through the speaker -- also called the "baseband audio." This discriminator source is required for applications such as Trunker, MTrunker, T4Win, and UniTrunker. Most scanners must have a simple modification made to them to output the discriminator audio output to a [[Data Slicer]], or in the case of UniTrunker, a soundcard.
+
The Discriminator output from a scanner is the raw, unfiltered signal that a scanner produces before it is sent to the audio stage for output through the speaker -- also called the "baseband audio." This discriminator source is required for applications such as [[Trunker]], [[T4Win]], [[UniTrunker]], and [[DSD]]. Most scanners must have a simple modification made to them to feed the discriminator output to [[Data Slicers]], or in the case of [[UniTrunker]], a soundcard.
  
Note that for providing a signal for ACARS applications, a plug from an earphone or speaker output is all that's required. This is because ACARS runs at a much lower speed, and the discriminator is not involved where AM demodulation is involved.
+
Note that for providing a signal for [[ACARS]] or [[MPT-1327]] decoding, a connection from an earphone or speaker output is all that's required. This is because these modes run at a much lower speed, and the discriminator is not involved in AM reception (for ACARS decoding).
 +
<br>
  
* See here for a list of discriminator output locations for many popular scanners - courtesy of Bill Cheek
+
==Modifications==
* See this [http://www.radioreference.com/digital/dig/bc895-tap.txt document] from Greg Knox regarding instructions on how to tap the discriminator output on the BC-895 Scanner. See this [http://www.radioreference.com/digital/dig/bc895-tap.jpg picture] for the location of the discriminator output on the 895.
+
Also see the [[Scandata faq q2]] article for a list of older scanners' tap points. This is from an original article written by the original scanner hacker and guru the late '''Bill Cheek'''.
* See Bill Cheeks [[SCANDATA.FAQ]] listed at the bottom of the page for detailed instructions on how to tap the discriminator in your scanner.
+
 
* Here are a few more sources of discriminator tap information;
+
'''Uniden'''
** [http://www.discriminator.nl/index-en.html Disciminator NL]
+
*[http://www.discriminator.nl/ubc245xlt/index-en.html BC-245 Discriminator Tap]
** [http://www.mods.dk/ Mods DK]
+
*[http://home.ica.net/~phoenix/wap/BC246T/ JPEGs of BC246 discrim tap]
** [http://groups.yahoo.com/group/RadioModifications/ RadioModifications Yahoo Group]
+
*[http://www.discriminator.nl/ubc3300xlt/index-en.html BC296D/UBC 3300XLT]
** [http://groups.yahoo.com/group/ScannerTech/ ScannerTech Yahoo Group]
+
*[[Installing a Discriminator Tap on a BC350A | BC350A Discriminator Tap]]
 +
*[[Installing a Discriminator Tap on a BC350C | BC350C Discriminator Tap]]
 +
*[http://myweb.accessus.net/~090/bc-780xlt.html#disctap BC-780 Discriminator Tap]
 +
*[[BC796D Discriminator Mod | BC785D Discriminator Tap]]
 +
*[[BC796D Discriminator Mod | BC796D Discriminator Tap]]
 +
*[[BC895 Tap | BC895XLT Discriminator Tap]]
 +
*[[media:Bc996discriminatortap.jpg|BCD996 Discriminator tap point]]
 +
*[[media:Bc996discriminatortap.jpg|BCT15 Discriminator tap point]]
 +
**NOTE:''' Look dead center of the circuit board, then go right and down. Both the 996 and BCT15 appear to share the same tap point location.
 +
 
 +
 
 +
'''Radio Shack'''
 +
*[http://www.discriminator.nl/pro-26/index-en.html Pro-26 Discriminator Tap]
 +
*[[Pro 93/95/96 Tap | Pro-93 Discriminator Tap]]
 +
*[[Pro 93/95/96 Tap | Pro-95 Discriminator Tap]]
 +
*[[Pro 93/95/96 Tap | Pro-96 Discriminator Tap]]
 +
*[http://www.naturalgfx.com/pro97_discriminator.htm  Pro 97 Discriminator Tap]
 +
*[[Pro-106 Discriminator Tap]]
 +
*[[Pro-164 Discriminator Tap]]
 +
*[[Pro 2052 Tap | Pro-2052 Discriminator Tap]]
 +
*[[Pro2053 tap | Pro-2053 Discriminator Tap]]
 +
*[[Pro-2066 Discriminator Tap | Pro-2066 Discriminator Tap]]
 +
 
 +
 
 +
'''Other Radios'''
 +
* [http://forums.radioreference.com/gre-scanners/85155-psr-500-discriminator.html PSR-500 Discriminator]
 +
* [[R7100 Discriminator Tap Notes]]
 +
 
 +
 
 +
==Why use a resistor and/or capacitor ?==
 +
See #6 through 8 of this URL: [http://www.discriminator.nl/faq/index-en.html Discriminator.nl FAQ]
 +
 
 +
[http://en.wikipedia.org/wiki/Low-pass_filter#Passive_electronic_realization Wikipedia Page showing Circuit and calculations for Discriminator Tap].
 +
 
 +
 
 +
 
 +
==Related Pages==
 +
These pages or links contain more information on discriminator taps for many brands and models of scanners, including older models
 +
* [http://www.discriminator.nl/index-en.html Discriminator NL]
 +
* [http://www.mods.dk/ Mods DK]
 +
* [[SCANDATA.FAQ]]
 +
 
 +
 
 +
 
 +
 
 +
 
 +
[[Category:RR Glossary]]
 +
[[Category:Receivers Glossary]]
 +
[[Category:Scanners Glossary]]
 +
[[Category:Signal Analysis and Decoding Glossary]]
 +
[[Category:Receivers Modifications]]
 +
[[Category:Scanner Modifications]]

Latest revision as of 16:11, 18 October 2020

The Discriminator output from a scanner is the raw, unfiltered signal that a scanner produces before it is sent to the audio stage for output through the speaker -- also called the "baseband audio." This discriminator source is required for applications such as Trunker, T4Win, UniTrunker, and DSD. Most scanners must have a simple modification made to them to feed the discriminator output to Data Slicers, or in the case of UniTrunker, a soundcard.

Note that for providing a signal for ACARS or MPT-1327 decoding, a connection from an earphone or speaker output is all that's required. This is because these modes run at a much lower speed, and the discriminator is not involved in AM reception (for ACARS decoding).

Modifications

Also see the Scandata faq q2 article for a list of older scanners' tap points. This is from an original article written by the original scanner hacker and guru the late Bill Cheek.

Uniden


Radio Shack


Other Radios


Why use a resistor and/or capacitor ?

See #6 through 8 of this URL: Discriminator.nl FAQ

Wikipedia Page showing Circuit and calculations for Discriminator Tap.


Related Pages

These pages or links contain more information on discriminator taps for many brands and models of scanners, including older models