P25RX P25 Phase 1/2/DMR Receiver With Bluetooth Audio Support
- Thread starter btt
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I have a cheap Bluetooth earpiece which I have been unable to pair successfully with P25RX. I have wired earbuds which work okay, but the volume is low. A wired external speaker I tried had audio so low as to be unusable.
Maybe I need more detailed paring instructions.
Maybe I need more detailed paring instructions.
Regarding U-Connect, I do have it listed as one of the two known devices that are reported not to work in the user-manual... If someone out there is familiar with 'C' and Bluetooth code, I'm willing to share source code if you want to take a shot at getting it to work. (send me a direct mail to discuss).
This is due to the recent changes made to the audio agc. Getting this right has been a moving target. Once again, I attempted to improve it for someone and ended up making it worse for others. I will be working on this today with a different approach. I will post here if it appears that progress has been made in getting it to work for all cases.
In the meantime, try increasing the agc audio max-gain level. See the Tips/Tricks section on the web site for more information.
This is due to the recent changes made to the audio agc. Getting this right has been a moving target. Once again, I attempted to improve it for someone and ended up making it worse for others. I will be working on this today with a different approach. I will post here if it appears that progress has been made in getting it to work for all cases.
In the meantime, try increasing the agc audio max-gain level. See the Tips/Tricks section on the web site for more information.
Correct me if I'm wrong, but isn't the analog audio output a "Line" output? A line output is, by nature, not designed to drive a headphone, let alone a full size speaker. It's designed to drive the input of another amplifier or mixer, recorder, etc. To drive a speaker you would need an external amplifier, same with a headphone. Also it's designed to drive an input impedance of around 10K ohms not the 4 to 36 ohms typically encountered with speakers and headphones.
I would use powered speakers or use a small amplifier.
It works great driving my Mackie mixer!
Line level audio: Line level - Wikipedia.
-Mike
I would use powered speakers or use a small amplifier.
It works great driving my Mackie mixer!
Line level audio: Line level - Wikipedia.
-Mike
That is good news!, but I do recall someone previously in the thread couldn't get U-connect 8.4 to work. I will change the user manual to "may work".I believe I have U-Connect 8.4 (can't see where to see the version) so it does work audio-wise. I can't help with code....I am familiar with C as the third letter of the alphabet and that's where my skill ends...
Mike, you are correct. The line-out audio is not designed to drive low-impedance. It is intended to drive a line-in (like on a sound card / sound system), or powered speakers.
For the wired earbuds you need an external headphone amp. Here's a portable one on Amazon: https://www.amazon.com/Headphone-Am...ble+headphone+amplifier&qid=1602169172&sr=8-3.
For the wired speaker any audio amp with sufficient power for the speakers used should work.
-Mike
btt - don't feel too bad about the Bluetooth issues; from reading thtough the Unication threads they are having their share of issues meeting full Bluetooth compatibility across a multitude of devices!
At least your device does have a regular analog line out (though no speaker).
-Mike
At least your device does have a regular analog line out (though no speaker).
-Mike
I looked through this growing thread to see if there's a list of console commands in one place. Did I miss it?
This is a FUN radio, and it's amazing how it's evolving before our eyes.
This is a FUN radio, and it's amazing how it's evolving before our eyes.
This is where the commands that haven't made it to the user manual are posted: P25RX Tips And Tricks
I'll work on documenting some more commands. You can see a few more if you do a '?' followed by 'enter' in the console.
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There is a new "testing" version on the web site 2020-10-08_1127. I think the audio AGC is improved a bit. In my case, I heard it clip with a couple of loud-voice speakers with the system volume way up. It didn't result in clipping in the recorded mp3 file, so I think it is ok. Looking at the recorded audio in audacity, it is apparent that the AGC is working better with this version (this is probably the most objective way to measure improvements). I've been listening on a Bluetooth speaker as well.
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The agc command in the 10/8_1127 version doesn't have the compressor threshold argument and the defaults have changed:
$ agc 2.5 0.33
Where 2.5 is fixed-gain and 0.33 is the rate.
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Hi Gang. I received my unit today; the signal strength is very weak compared to my SDS-100 (10dBm difference with the SDS winning) and audio on voice channels is quite choppy, resembling Simulcast Distortion issues of the past. I feel like I'm doing something wrong. I started with 10-2 then switched to 10-8, which was a little better. Any suggestions? I'm already using the upgraded antenna the unit came with.
Hi Matt,
When you say the SDS-100 has a 10dB stronger signal, you mean that you have them in the same general area and they are reading 10dB difference correct? What sort of levels are you seeing for the "RF Sig Level" during the times where there is choppy voice? Does the I/Q symbol plot change when there is choppy voice?
Matt,
One thing to check... Did you try putting the mag-mount antenna on top of a metallic ground plane?
Another thing to check... The default "talk group timeout" is 2 seconds. If you have a lot of activity going on, this can cause a discontinuity in the voice when it switches over to different talk groups. You might try setting this to 100ms and see if that helps.
One thing to check... Did you try putting the mag-mount antenna on top of a metallic ground plane?
Another thing to check... The default "talk group timeout" is 2 seconds. If you have a lot of activity going on, this can cause a discontinuity in the voice when it switches over to different talk groups. You might try setting this to 100ms and see if that helps.
Todd - Yes, same area with at least 10db difference. During choppy audio it's reading 94-100 on the CC. At the same time, my SDS-100 is reading 85db on the CC - It's almost as if I've enabled an attenuator. I tried the antenna on a metallic ground plane which helped some. I finally found my Remtronix 800Mhz hi gain antenna which has helped a bit, bringing the RSSI to about 89db and clearing up the audio a bit but there is choppiness.
The I/Q Plot is all over the place, going between red and green with sync state either 1, 0, or -2.
I tried setting talk group timeout to 100ms but that didn't help at all.
Thanks for you quick reply and support - It's appreciated more than you know!
*On a voice channel (same frequency) the SDS-100 is at 50db and the P25RX is at 89db. The radios are right next to each other and the P25RX is using the good Remtronix 800Mhz antenna. This concerns me that the P25RX receiver is in some sort of attenuation mode.
The I/Q Plot is all over the place, going between red and green with sync state either 1, 0, or -2.
I tried setting talk group timeout to 100ms but that didn't help at all.
Thanks for you quick reply and support - It's appreciated more than you know!
*On a voice channel (same frequency) the SDS-100 is at 50db and the P25RX is at 89db. The radios are right next to each other and the P25RX is using the good Remtronix 800Mhz antenna. This concerns me that the P25RX receiver is in some sort of attenuation mode.
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39dB difference between the two definitely doesn't sound right. I can say it was tested with a signal generator before it was shipped and it is doubtful that it quit working during shipping. When the input signal from the antenna is at -89 dBm, you should be seeing a "fonrt-end RF gain" of 38 dB. Is that what it is showing?
Could you post a representative screenshot of the I/Q symbol plot?
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If you aren't able to figure out anything, please contact me via e-mail. It may be that something did happen in shipping.
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The current testing version is 2020-10-08_2119. The audio AGC appears to be working great with the changes for today. No clipping heard and no clipping showing up in the recorded audio. Quiet talkers are audible. If you have a chance to test, please report how it is working for you.
I have just downloaded the testing version 2020-10-08_2119 software. It seemingly updated my firmware automatically, without any intervention from me! If so, great!
This version working well so far, audio sounds great; this is with the device connected to the PC using the PC speakers.
Question: I was experimenting with various inside and outside antennas to test the effects on reception. When using a particular 800MHz band outside antenna (on an 800MHz trunking system), I was seeing four bars on the RF Sig Level meter, and -85 dBm, but the SIG light was not lit, and I got poor or no decoding. But when I changed to a different antenna, I got only one to one and a half signal bars, -103 dBm, but the SIG light was green, and I got good decoding. Could this be an overloading issue with the first antenna?
This version working well so far, audio sounds great; this is with the device connected to the PC using the PC speakers.
Question: I was experimenting with various inside and outside antennas to test the effects on reception. When using a particular 800MHz band outside antenna (on an 800MHz trunking system), I was seeing four bars on the RF Sig Level meter, and -85 dBm, but the SIG light was not lit, and I got poor or no decoding. But when I changed to a different antenna, I got only one to one and a half signal bars, -103 dBm, but the SIG light was green, and I got good decoding. Could this be an overloading issue with the first antenna?
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