AGC (on 996T and 396T)

[ACU1000]

As long as we are asking questions... I have a senario where the conventional systems audio levels seem alot higher in volume level than the digital systems do.

I know there are some toggles I can do to Enable Analog AGC and Enable Digital AGC, but not sure which combination of enabling I want to best remedy the problem I describe above.

Anyone?

 

[UPMan]

First, ensure that the receive mode is correct. If the conventional system is transmitting 25 kHz FM, but the scanner is set to NFM, it will sound louder due to overmodulation.

 

[mike_s104]

As long as we are asking questions... I have a senario where the conventional systems audio levels seem alot higher in volume level than the digital systems do.

I know there are some toggles I can do to Enable Analog AGC and Enable Digital AGC, but not sure which combination of enabling I want to best remedy the problem I describe above.

Anyone?

welcome to the latest firmware version from Uniden. THANKS!!! it happened after the latest creation they put out. for the 396T, a downgrade of the firmware version will fix that but you'll lose WANC and apparently some other "fixes". as for the 996T, there is no prior firmware available because it seems they follow the same wisdom that Butel does.

 

[ACU1000]

First, ensure that the receive mode is correct. If the conventional system is transmitting 25 kHz FM, but the scanner is set to NFM, it will sound louder due to overmodulation.

UPMan:
I have double checked the settings and its AUTO (not NFM).
I assume AUTO is acceptable for the mode?
Or, can the scanner not detect conventional system mode correctly?
I guess I am asking is, do I need to manually set the scanner to a specific rec mode for an old analog conventional system that uses standard 25khz channel spacing and 5khz deviation in audio modulation?
Do I need to set it to FM manually?

As a side note, what do the AGC analog and AGC digital settings do then?

 

[MarkEagleUSA]

I have double checked the settings and its AUTO (not NFM).

On the 396, AUTO is NFM

Do I need to set it to FM manually?

If that what it really is, yes you need to set it manually.

 

[rvrman]

396T Newbie

I have downloaded ARC396 I went on this web site and was able to see a few local frequencys my question is if one was to subscribe to radioreference.com will it give you access to more local frequencys and more information? Thanks in advance

 

[mike_s104]

I have downloaded ARC396 I went on this web site and was able to see a few local frequencys my question is if one was to subscribe to radioreference.com will it give you access to more local frequencys and more information? Thanks in advance

no more info than actually looking in the RR DB. it just allows you to download data directly to ARC396 within the application.

you may want to post and look for specific questions relating to software under the software forum, you'll receive better and faster replies.
http://www.radioreference.com/forums/forumdisplay.php?f=89

 

[ACU1000]

On the 396, AUTO is NFM

If that what it really is, yes you need to set it manually.

Am I stuipd, AUTO should be AUTO. UPMan???

Can someone confirm that the AUTO setting automatically means its chooses NFM?

 

[UPMan]

Auto picks the mode according to the current FCC band plan. In most areas, the FCC is requiring new licensees to use NFM, so in much of all bands, NFM is the AUTO setting. However, there are still quite a few legacy licenses that are still allowed to use FM.

 

[ACU1000]

Okay, so I understand that AUTO is not automaticlly selecting the transmitted mode, but selecting a pre-set based on an pre-programmed band-plan. Thanks.

However, for me to manually correct my system files, I would logically think I needed WFM on a conventional VHF-HIGH police type frequency. But you are telling me to select FM (and the RR db shows FM - see this system in the db.) Which do I need to select, FM or WFM?

Lastly, if the RR db for this system is showing FM as the MODE, how come when I do an import the data for MODE shows up as AUTO - is this a flaw in the RR db or the import of the Butel software, the API, or dumb user error?

Please reply...

 

[UPMan]

You should pick FM. WFM is for broadcast FM (88-108) or TV.

I don't know how the ARC software is supposed to work (but ask me something about UASD! ).

 

[ACU1000]

Some more follow-up questions...

a)
For a non-trunked P25 channel like below, I would select NFM, correct ?

Frequency License Type Tone Description Mode Tag 460.26250 WQAV791 M APCO-25

b)
Has anyone encounted a mode referred to as P25-5 (where they are not in narrow mode) and if so how is that noted in the RR db?

c)
Anyone have the settings for all the different MOTO XTN frequencies (I know some our 12.5 and some are 25khz spacing)? Otherwise would it hurt to set them all to FM? I know some people use the itinerant freqs in their old 5 watt programmable business band radios and thus are transmitting in FM.

d)
Also, what setting would you suggest to use for known federal frequencies (since they all seem to be gradually switching to P25, would you choose AUTO?)

e) Is it in the Uniden manual some where that explains what AUTO setting is used for each band plan or are we just saying that it follows the current FCC rules per band plan these days and if so where is that list?

 

[mike_s104]

Some more follow-up questions...

a)
For a non-trunked P25 channel like below, I would select NFM, correct ?

Frequency License Type Tone Description Mode Tag 460.26250 WQAV791 M APCO-25

b)
Has anyone encounted a mode referred to as P25-5 (where they are not in narrow mode) and if so how is that noted in the RR db?

c)
Anyone have the settings for all the different MOTO XTN frequencies (I know some our 12.5 and some are 25khz spacing)? Otherwise would it hurt to set them all to FM? I know some people use the itinerant freqs in their old 5 watt programmable business band radios and thus are transmitting in FM.

d)
Also, what setting would you suggest to use for known federal frequencies (since they all seem to be gradually switching to P25, would you choose AUTO?)

e) Is it in the Uniden manual some where that explains what AUTO setting is used for each band plan or are we just saying that it follows the current FCC rules per band plan these days and if so where is that list?

A) Yes
B) No
C) Not sure, but I would guess FM
D) Auto and not set the CTCSS/PL to search on a 396T, on a 996T you can enter them in twice; set one to search and the other to digital only.
E) Current FCC rules

feels like a test...how'd I do?

 

[ACU1000]

A) Yes
B) No
C) Not sure, but I would guess FM
D) Auto and not set the CTCSS/PL to search on a 396T, on a 996T you can enter them in twice; set one to search and the other to digital only.
E) Current FCC rules

feels like a test...how'd I do?

Mike,

I think I am not convienced with the answer to C - but not sure.

Where do I see a table or list of E ?

 

[ACU1000]

Here is a table for the xtn frequencies - see some are wide and some are narrow.

I assume I need to set MODE to NFM for the narrow ones ;-)

http://www.astracomm.com/XTN/frequencies.php

 

[razzlefratz]

You should pick FM. WFM is for broadcast FM (88-108) or TV.

I don't know how the ARC software is supposed to work (but ask me something about UASD! ).

Um, if WFM is broadcast FM, then what is FMB?

Any chance that you could correlate the bandwidth settings to FCC license data for emission type, eg 20K0F3E?

 

[Bote]

You certainly could use the FCC emissions designator to determine how to program your receive bandwidth. Since I have never seen Uniden's specification for the bandwidth of each mode on the 996 you still would not have a quantitative means of comparison, since I have seen the term narrowband thrown around loosely over the years by various vendors. Give me numbers.

Or you could just set it and try it out. It's not like it's etched in ROM once you program the thing. If it splatters outside the passband, then I guess you should bump it up to FM mode.

It is good practice to use the narrowest receive bandwidth available to get the job done. This gives you maximum signal/noise ratio. Widening your receive bandwidth reduces your signal/noise ratio, so you will reduce your receive performance by widening from NFM to FM mode in your scanner.

I find that NFM works great on legacy systems, so either Uniden's filtering is only so-so (no surprise) or every single conventional transmission that my box receives is significantly under-deviated. I mean railroads, police, fire, radios that I mess with at work, you name it...a diverse group. If nobody had told me otherwise, I would have thought NFM is the desired mode for current systems on the air.

 

[janderson18]

I'm a novice scanner opperator trying to program my 996T from this computer. I downloaded Uniden's Advanced Scanner Director software. Now what? I'm pluged in and ready to go. Pinellas County Florida is what I want to program/download. Thanks, Jeff