Unitrunker won't pick up anything

[neonhomer]

I am using a Pro95 and the latest Unitrunker. I checked to make sure I am getting good audio through UniScope. However, Unitrunker keeps telling me "No Signal". I am trying to scan EDACS.

I have the scanner plugged into the mic in jack on the sound card, and I am using the headphone jack on the scanner. I turn the scanner on, and adjust the volume so it is not clipping in UniScope. I tune to the control channel. The scanner display shows the different groups that it is decoding.

Using a SB Audigy and Windows XP Pro SP2. I know I have the source configured right because I can select the mic monitor and hear the control channel.

Config from Options:

Auto Save Off
Display Mode Decimal
Signal is Auto
Decoder is Online
Logging is Off
APCO P25 is ON

Recievers
Signal Input Default Sound Device
Sample Rate 44100
Sample Bits 16
Voice Radio none


What am I doing wrong?

 

[SCPD]

Hi Neon;

I have the scanner plugged into the mic in jack on the sound card, and I am using the headphone jack on the scanner.

The only trunking protocol where that will work is MPT1327. For EDACS, the radio's speech filters distort the waveform. The filters are designed to reduce hiss - not pass a 9600 baud squarish waveform. You'll need to tap the audio from the radio before it has been filtered. This requires modifying the radio so that the unfiltered discriminator audio signal can be brought outside the radio and fed into your computer's microphone input.

I think there's a section of the wiki that covers this.

-rick

 

[neonhomer]

The discriminator pin is right inside the unit. Do I need to feed the discriminator pin to the mic input, or do I have to go through a data slicer?

Either way, I have to wait until next year before I open the unit, as it still has an extended warranty on it until the end of December.

 

[Deeke]

Homer, find a cheap, used scanner to tap. I found a Pro-24, 16 ch 800 Mhz handheld for $9 + $4 shipping on ebay. You can run it using Unitrunker and use the new scanner to listen to.

 

[SCPD]

The discriminator pin is right inside the unit. Do I need to feed the discriminator pin to the mic input, or do I have to go through a data slicer?

The slicer is only needed if you're using a serial port and (mostly) DOS software.

You can feed the signal directly ... although it would be better to provide some isolation int the form of a 2.2 uF or larger cap or a 10k ohms (or more) restistor or a small buffer amp. As Deeke suggests, most folks use an older radio for decoding. If it can tune the band(s) you want, it should work. It doesn't need to support trunking or digital audio.