Please explain 396 "tweak"

[ButchGone]

OK, I see the 396 digital AGC tweak page on the WIKI and understand what the instructions say to do. But to help me understand what these settings mean and to better tweak to my systems, please explain what the "P25 RES Time" and P25 REF gain" values mean. What does a minus value mean in terms of reception versus a positve value? Understanding what the values mean may help me and others trying to tweak 396's.
Thank you in advance!
BG..

 

[N9AWO]

I think that's a great question. I would like to know as well. Hope someone has the answer.

 

[a29zuk]

We tried this before........maybe this time we'll get an answer

 

[John_M]

The basic instructions for the AGC can be downloaded from Uniden. The only people who could specifically tell you what "P25 RES Time" and P25 REF gain" mean would be somebody from Uniden. It is a control system just like the thermostat in your home. In / Out with feedback. Paul should be able to shed some light on the subject. The Digital AGC tweak is listed as being Unofficial and not supported by Uniden (yet). They may change things
in a firmware update.

 

[John_M]

In

(parameters)

Out

(feedback with/without parameters) Out

In

At least this is how I believe it works.

 

[slicerwizard]

please explain what the "P25 RES Time" and P25 REF gain" values mean.

RES Time (P25 or ANA) controls how frequently the scanner will adjust the volume, hence how quickly it will respond. Lower values = faster response (e.g. less time delay between adjustments). Very low values can trigger "pumping", where the volume jumps up and down.

REF Gain (P25 or ANA) sets the target volume level. They can be used to match analog and digital volume levels.

Negative values just represent the lower end of the adjustment ranges. Typically, zero represents a "normal" or default setting, while negative values represent below normal settings.

 

[wjf]

[

RES Time (P25 or ANA) controls how frequently the scanner will adjust the volume, hence how quickly it will respond. Lower values = faster response (e.g. less time delay between adjustments). Very low values can trigger "pumping", where the volume jumps up and down.

REF Gain (P25 or ANA) sets the target volume level. They can be used to match analog and digital volume levels.

Negative values just represent the lower end of the adjustment ranges. Typically, zero represents a "normal" or default setting, while negative values represent below normal settings.

"John_M:

(parameters)

Out

(feedback with/without parameters) Out

In

At least this is how I believe it works."


Thanks. I'm still dizzy about the craziness John_M posted!

 

[John_M]

wjf Wrote:

"John_M:

(parameters)

Out

(feedback with/without parameters) Out

In

At least this is how I believe it works."


Thanks. I'm still dizzy about the craziness John_M posted!

This is what I was trying to draw with the arrows.

Block diagram of control system:

http://www.tpub.com/content/doe/h1013v2/css/h1013v2_117.htm
Ideally you want it to act as fast as possible to give you the desired output level
(Volume).

 

[UPMan]

Except that if you have it acting too fast, the AGC will "pump" which would give everyone a nice vibratto (and drive you nuts after a while).

 

[a29zuk]

That clears it up! I'll be tweaking some more.

Thanks

 

[ButchGone]

Well now I've tried the digital tweak with no avail. The instructions in WIKI say power up the 396 while pressing the Hold button. I've done this many times and no tweak menu appears. It only goes into normal scan mode. Any suggestions? The firmware version is 1.11.04. Thanks.
BG..

 

[rvawatch]

turn on one of the agc modes through the settings menu, turn off the scanner, press "hold" and "power" to turn the scanner back on, hold "func" and press the knob twice (like how you get to the decode rate), you are now at the agc menu. Hold "func" and scroll with the knob to choose the different selections.

 

[ButchGone]

Thanks! Your instructions clarified one step I was missing.
BG..

 

[Bote]

Press Scroll knob twice

The tweak instructions are not clear.

It says to press and hold Function while tapping the Scroll knob once, but then you must wait 10 seconds for the squelch setting to disappear to reveal the AGC tweak setting.

Pressing Scroll a second time clears the squelch adjustment thermometer so that you can see the AGC setting on the bottom line. Alternate AGC settings by holding F and scrolling between them. Let go of F to change the actual numerical setting (tweak it).

I just changed mine, but I actually like the AGC off on the Boca Raton digital trunked system. The AGC just cuts back way too wildly at the start of transmissions for my tastes.

 

[ButchGone]

I agree, I like the sound of the 396 withouth the AGC on. The same was true when I briefly had the Pro 2096, which on that model made the digital audio sound more watery. Mileage varies, I guess, since some Moto systems just sound better than others.
BG..