BCT15: BCT15 not receiving data bursts?

[Signal3and2]

I have a weird problem with my BCT15. In my area analog public safety is nearing extinction, so I thought I'd use the BCT15 to receive amateur radio APRS packets and set up a RX-only I-Gate.

Oddly enough, I cannot get the scanner to audibly or visually receive APRS packets (AX.25 data). I have the scanner set to 144.390 (APRS in United States).

I have tried changing the modulation, just in case.
I have checked that DATA SKIP is OFF
I have checked that CTCSS is OFF
I have a 2M radio right next to it that is receiving and audibly playing the packets through the speaker
I switched antennas with the 2M radio, just in case
The scanner is receiving analog voice from distant-ish repeaters just fine (up to 40 miles away) in the VHF range.
I had a friend with an SDS100 monitor the same frequency, just in case it was a "Uniden" thing, but he can hear them fine. (I understand we are worlds apart in scanner technology between the 2 scanners).

At no time do I hear packets, have the squelch broken, or see the signal meter change at all despite knowing there are strong packet signals present.

Any ideas? What am I missing?
Thanks

 

[dave3825]

Are the packets able to be decoded by that scanner? I mean is their modulation a modulation the scanner supports?

 

[krokus]

I have a weird problem with my BCT15. In my area analog public safety is nearing extinction, so I thought I'd use the BCT15 to receive amateur radio APRS packets and set up a RX-only I-Gate.

Oddly enough, I cannot get the scanner to audibly or visually receive APRS packets (AX.25 data). I have the scanner set to 144.390 (APRS in United States).

I have tried changing the modulation, just in case.
I have checked that DATA SKIP is OFF
I have checked that CTCSS is OFF
I have a 2M radio right next to it that is receiving and audibly playing the packets through the speaker
I switched antennas with the 2M radio, just in case
The scanner is receiving analog voice from distant-ish repeaters just fine (up to 40 miles away) in the VHF range.
I had a friend with an SDS100 monitor the same frequency, just in case it was a "Uniden" thing, but he can hear them fine. (I understand we are worlds apart in scanner technology between the 2 scanners).

At no time do I hear packets, have the squelch broken, or see the signal meter change at all despite knowing there are strong packet signals present.

Any ideas? What am I missing?
Thanks

You said CTCSS is off, how about DCS?

How close are the transmitters? Is the radio suffering desense?

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[Signal3and2]

It's not a supported data protocol on this scanner, but I'm just looking for the raw, undecoded audio from the scanner.

 

[Signal3and2]

You said CTCSS is off, how about DCS?

How close are the transmitters? Is the radio suffering desense?

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Transmitters are all mobile, so distance will vary. DCS is off. Desense unlikely, there are no strong VHF signals present in my immediate area and I don't detect anything on other VHF radios I have here nor do I see anything on a basically spectrum analyzation with an SDR.

 

[wtp]

and the squelch is set at....?

 

[scan-pa]

You need a discriminator output most likely.

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[Signal3and2]

and the squelch is set at....?

I've tried it at "just muted", and also all the way open.

 

[Signal3and2]

You need a discriminator output most likely.

Sent from my SM-G935V using Tapatalk

So you think that the scanner is filtering out the data burst? What would be the point of the receiver having a "Data Skip" option if it wouldn't pass data through the audio filtering circuit to the speaker in the first place?
Just thinking out loud.

 

[dave3825]

Do you have an sdr dongle?

 

[mancow]

You don't need a discriminator output for AX25 packet.

 

[kb7gjy]

if you are plugged into the rec out is recording enabled?

 

[wtp]

could you try the HOLD, FREQ, HOLD quick way of receiving it ?

 

[krokus]

could you try the HOLD, FREQ, HOLD quick way of receiving it ?

Good point. Is the scanner parked on 144.390, or scanning?

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[Signal3and2]

Thanks so far everybody. The scanner is parked on 144.390, and not scanning. I don't have any audio patch cables hooked to it, I'm only listening through the built-in speaker at this time (I didn't want to bother to buy an audio cable until I got the scanner part working).

Yes, I do have an SDR dongle, but I use it for other stuff so I wouldn't be able to leave it parked on a freq dedicated to APRS.

And mancow, thank you for the info.

 

[krokus]

Have you used your SDR to do a spectrum sweep? Making sure there is no other conflicting signal?

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[Signal3and2]

I have, last night I listened to 144.390 with the SDR for quite a while and heard nothing except the data bursts I was expecting.

Have you used your SDR to do a spectrum sweep? Making sure there is no other conflicting signal?

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Interestingly, I acquired an old-school BC785D (no P25 card installed), and am getting the same result on it as I am with the BCT15.