Pro-652: Over modulated w/P25...

[tdave365]

Hi, I have a number of P25 mode channels using conventional 450.000 frequencies (Buffalo, NY PD in particular) that are for lack of a better description, over-modulated. I receive signals fine but on one or two channels everything comes in just too loud! Imagine if you had a TV channel where the audio level was the same acceptable level on 12 channels but then super loud, for no reason, on Channel 13. That's what this is like. What's more, the frequency this most happens on, is not only loud, it's difficult to decipher what is being said unless one focuses very intently on it.

It makes general scanning difficult. I have to reach down and turn down the volume whenever this channel opens up. Which brings up the other weird facet which is that the line between HIGH volume and LOW volume is really narrow. It's easy to turn it down or up too much by accident.

So my question is is there any radio tuning control that might improve this? I interface using the Win500 control software and have access to a lot of controls but I understand nary what most of them really do or any of them would really help on this one channel.

Or, is this just a feature of how the engineers have programmed the operation of this channel, or the nature of the PRO-652 itself. I would find the latter hard to believe because I get other channels clear and at an acceptable volume level. It is just this one or two P25s that are driving me crazy.

 

[mikey60]

You can try turning on AGC on the radio. The transmissions may seem a little muffled (or under water) in that case but the levels should be more even.

Some systems have AGC enabled, others don't. When enabled on the systems all of the levels tend to be pretty consistent. When not enabled, they can be all over the place.

Mike

 

[tdave365]

Found that, thanks! The advice helped albeit indirectly. AGC for this channel was already checked but as it was a lead I decided to play around with both it and the modulation setting which is something I had overlooked but found on the same page of controls as the AGC. I found that by selecting NFM or FM as a mode dramatically improved things, even though RR lists (and accurately we can safely assume) the mode as being P25. So, I am not sure why when selecting the FM modes improves the audio volume and quality when the channel is a P25 but it IS working much better now. Thanks for the tip!