325P2 trunk no decode...

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milcom_chaser

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Trying to do a Control Channel only search in the 851-859Mhz Band. Radio seems to trunk ok on Phase II system once it finds the control channel, but does not decode fully, just digital white noise. Also, tried using the custom band plans from the manual on page 53 with no luck.

Bandplan 1 851.025, 854.0000, 440, +, 25 kHz (base, upper, offset, spacing)
Bandplan 2 851.0125, 868.9875, 0, +, 25 kHz

Also, changed the spacing, and offset - no luck.

The system were trying to do a control channel only search is a Project 25 Phase II, Voice: APCO-25 Common Air Interface Exclusive. Non encrypted.

The radio trunks and decodes fine as a programmed system, but again, as a control channel only mode for this system, no luck.

What are we missing here?
Thank you big time.
 

UPMan

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MENU --> Srch/CloCall Opt --> Tone/Code Search

Set to "Off" or "NAC/Color Code". If set to "CTCSS/DCS" all comms are forced to analog.
 

milcom_chaser

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MENU --> Srch/CloCall Opt --> Tone/Code Search

Set to "Off" or "NAC/Color Code". If set to "CTCSS/DCS" all comms are forced to analog.
I checked that too, it was off before programming a custom search.
Thanks tho.
Any other ideas?
 

milcom_chaser

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Additionally, the radio does display the SID, group ID, the control channel frequency, the voice channel frequency. It just won't decode the audio other than playing digital noise.

This is a multi-site system. Shouldn't really matter, it's a control channel from a found site.
 

ofd8001

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Let me get this straight - are you monitoring the control channel as if it was a conventional frequency?

(If you do "listen" to a trunked system's control channel as if it were a conventional frequency all you will hear is "noise".)
 

milcom_chaser

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Let me get this straight - are you monitoring the control channel as if it was a conventional frequency?

(If you do "listen" to a trunked system's control channel as if it were a conventional frequency all you will hear is "noise".)
"Trying to do a Control Channel only search in the 851-859Mhz Band."
 

ofd8001

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I'm sorry, I still don't understand what your are trying to accomplish: Are you searching from 851-859, hoping to find a control channel for a trunk system, and then once finding that control channel, decode that control channel as if you had the system programmed as a trunked system?
 

milcom_chaser

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I'm sorry, I still don't understand what your are trying to accomplish: Are you searching from 851-859, hoping to find a control channel for a trunk system, and then once finding that control channel, decode that control channel as if you had the system programmed as a trunked system?
Yes.

"Radio seems to trunk ok on Phase II system once it finds the control channel, but does not decode fully, just digital white noise. Also, tried using the custom band plans from the manual on page 53 with no luck.

Bandplan 1 851.025, 854.0000, 440, +, 25 kHz (base, upper, offset, spacing)
Bandplan 2 851.0125, 868.9875, 0, +, 25 kHz

Also, changed the spacing, and offset - no luck.

The system were trying to do a control channel only search is a Project 25 Phase II, Voice: APCO-25 Common Air Interface Exclusive. Non encrypted.

The radio trunks and decodes fine as a programmed system, but again, as a control channel only search mode for this system, no luck."
 

ofd8001

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I don't believe the scanner will do that.

The manual does use the words "CC search in 851-859 band" but that means "Close Call" and not "Control Channel".

Close call is a nearby transmitter. So a "CC search in the 851-859" band means you are looking for a nearby conventional transmitter that is operating in the 851-859 band.

The scanner doesn't "deal" with trunked systems control channel searches because the scanner needs to know the type of system it is dealing with, which is something set in the programming of the scanner.
 

milcom_chaser

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I don't believe the scanner will do that.

The manual does use the words "CC search in 851-859 band" but that means "Close Call" and not "Control Channel".

Close call is a nearby transmitter. So a "CC search in the 851-859" band means you are looking for a nearby conventional transmitter that is operating in the 851-859 band.

The scanner doesn't "deal" with trunked systems control channel searches because the scanner needs to know the type of system it is dealing with, which is something set in the programming of the scanner.
No. Read further in the manual. In custom search, the user can set the radio to search for "Control Channel Only"

Menu>Search For>Edit Custom>Select Custom>'Your Search Choice'>Set C-Ch Only>C-Channel Only Mode.
 

ofd8001

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If I read your post correctly, you are describing a P25 system. The manual uses the terms (Motorola and LTS systems). The formats are different in P25 systems versus Motorola (noting that Motorola may make P25 systems, a P25 system format is different from a "Motorola" format).

So while you may get some type of response, you may not be getting "everything" due to format differences.
 

milcom_chaser

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I just confirmed using Unitrunker and a second radio, that the 325P2 is indeed trunking to the correct voice channel, it is not decoding audio correctly. Perhaps this is a firmware issue.
 

milcom_chaser

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If I read your post correctly, you are describing a P25 system. The manual uses the terms (Motorola and LTS systems). The formats are different in P25 systems versus Motorola (noting that Motorola may make P25 systems, a P25 system format is different from a "Motorola" format).

So while you may get some type of response, you may not be getting "everything" due to format differences.
P25 is a communication standard which manufacturers use in the design/production of their radios.
Motorola represents one line of radios that employ the P25 standard...

If you read the manual, the bcd325P2 is capable of trunking a number of systems:

• Motorola Type I
• Motorola Type II
• Motorola Type IIi Hybrid
• Motorola Type II Smartnet
• Motorola Type II Smartzone
• Motorola Type II Smartzone Omnilink
• Motorola Type II VOC
• Project 25 Standard
• Motorola X2-TDMA
• P25 Phase I and Phase II

So, rather than debating the semantics of the wording, click on the link to the video of the radio trunking a single control channel, and listen to the audio...

Thank You.
 

milcom_chaser

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Not much help, but I'd venture to guess those are TDMA TG's it's trying to go to.
Yes, the talk groups are TDMA. Interesting that as a programmed system, it decodes fine, but when doing a Control Channel only search in the 851-854 band, the radio will start trunking when it finds the site control channel, but won't decode the voice channels...
 
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