Batboard

For the longest time my XTS3000 has had a funky echo sound to it while receiving a transmission. I often listen to other radios at the same time and figured it was just the effects of hearing two radios at the same time (Stereo effect). Recently I have just been listening to the XTS. The echo in the audio is still there. It is really just a nuisance and does not affect the audio quality. I have looked through CPS to see if there is anything that could be changed to improve audio but have been unable to find anything. Does anyone have any idea what could be causing this and how I might correct it?

Thanks in Advance.

Mark

PS. The radio works flawlessly otherwise. RX and TX are rock solid

Is this in analog, or digital?

This would be in analog conventional operation. UHF band just as an FYI.

I have noticed this before. Astros & XTS's. Many times at hamfests, with people talking simplex, I have noticed slight echoes. Never annoying. I just figured that's what a digital radio sounds like in analog. Hope this helps. 73's GARY N4KVE

All ASTRO radios exhibit an audio delay of about 40 msec due to the slight delay that occurs in the audio DSP, even in the analog mode.

My AS3 does the same thing. It has to do with the DPS audio circuit. Even in analog mode, the DSP is still used. This is completely normal for Astro type radios.

Some of the newer radios being produced that are not digital Astro contain from what it sounds like the same DSP for RX/TX. One of the newest radio from /\/\otorola that is not digital, but contains the DSP is the PR1500/MT1500. These radios have the same "echo" effect.

BTW, the "echo" effect doesn't bother me at all. The audio is very clean and easy to understand/decypher.

As we move toward software-defined radios, more and more cleanup/filtering is being done in DSP. Expect to see more radios using DSP with every passing day...

You only notice the display when mixing analog and digital radios in the analog mode.

Uh, not quite true. Try speaking into your ASTRO Transmitter, and then monitor the output on an ASTRO receiver within earshot range. You will hear a very noticeable delay between what your ears hear when you speak into the TX, and the RX's recovered audio. This will be the case whether the radios are in in the anlog FM mode, or the IMBE mode. Try it, and you'll see.

Sorry, the brain isn't working right since I'm out with the flu... I meant to say its most notable when in analog mode around analog radios. Of course its present in digital mode as well.

Even the PR1500 has a delay. It has analog only DSP in it.

tpg

ASTROMODAT wrote:Uh, not quite true. Try speaking into your ASTRO Transmitter, and then monitor the output on an ASTRO receiver within earshot range. You will hear a very noticeable delay between what your ears hear when you speak into the TX, and the RX's recovered audio. This will be the case whether the radios are in in the anlog FM mode, or the IMBE mode. Try it, and you'll see.

However, the delay in analog borders on 'imperceptible', while in IMBE it is much longer, due to the actual conversion taking place.

Todd

I did some more tests and found that only when I have my radio next to another analog radio like my MT2000 you can definitely hear the difference. Stand alone the audio is excellent. It makes sense that the radio having to process an audio signal through a DSP would take a bit longer than a radio that does not. Thanks to all for your comments. It has been very enlightening.

Mark

The delay isn't noticable in analog, but the echo that results is very prominent!

It's a very distinctive sounding echo.