Where are the BCDx36HP Users in Maryland?

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emtLarmy15

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Mar 23, 2003
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Pocomoke City, MD
Overnight I was getting VA STARS out of accomac up at the Wor/wic line on 12 and up as far as Newark (didn't go further north)... It's a really strong system


Sent from my iPhone using Tapatalk
 

troymail

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I can say that the 536 is really good at receiving "distant" systems (if you consider 10-15 miles "distant") - better than other radios I have. This is both good and bad - particularly for digital and/or P25 system. The good part is I can hear things - the bad part is that it's very inconsistent because of the distance - I know there is activity that I am not hearing and then once in awhile I can hear it. Also, when I do hear it, it can be a bit choppy... but at least I can usually make out what they are saying.
 

MacGnG

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Got a quick question I couldn't figure out (looked in the manual, maybe I'm missing something). how do i make the time delay longer on my 436 after the sound stops before it goes to the next frequency. this should be easy to figure out… maybe its just been a long day. any help would be appreciated!
 

troymail

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Got a quick question I couldn't figure out (looked in the manual, maybe I'm missing something). how do i make the time delay longer on my 436 after the sound stops before it goes to the next frequency. this should be easy to figure out… maybe its just been a long day. any help would be appreciated!

Through the radio you have to drill down to each talkgroup or channel one at a time and then change the Delay setting.

Menu
Manage Favorites
<select your favorites list>
Review/Edit System
<select your system>
Edit Department
<select the department>
Edit Channel
<select the channel>
Set Delay Time

In Sentinel, you can change them more easily through Edit Favorites List.
 

MacGnG

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Well that's silly!! Should be a global preference ... Thanks

I'll do that just on my SHORT favorites list.
 

dwlipp

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Feb 3, 2003
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Location
Montgomery County, MD
BCD436HP Montgomery County Tweaks

Since I have had my 436 I have been somewhat disappointed with its performance decoding Montgomery's system, however, I think I may be cracking the code now. Here are the tweaks I have made as compared to an 'out of the box' configuration.

Firmware - 1.03.00
Squelch - 2

Under Options in the Site:
Modulation - FM
P25 Threshold - 11
P25 Threshold Mode - Manual

I am not sure whether the firmware update has really impacted the decoding performance or not, or whether the improvement is just the cumulative impact of the other tweaks, but at this point the 436 is matching (or maybe even ever so slightly doing better than) my 396XT when decoding the Montgomery system. Prior to these tweaks I was consistently getting choppy audio from the 436 with decoding error rates in the ~55-65 range (viewed in P25 adjustment mode; page 59 of the Owner's Manual). With these changes in place the audio actually sounds quite good and the error rates are in the ~15-25 range tracking with my 396XT sitting right beside it, or even doing a bit better from time to time.

I am still not sure why leaving the 426's P25 Threshold Mode in the Auto configuration isn't working the same way as the 396XT where the level quickly adjusts from the default level of 8 to an optimal level of 11, but I can live with things the way they are now. It would be better if the Auto mode actually worked automatically as it does in the 396XT so you wouldn't have to run through trial and error testing to figure out what the setting for a given system should be but for the time being it is what it is.
 
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troymail

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Supply (Lockwood Inlet area), NC
It would be better if the Auto mode actually worked automatically as it does in the 396XT so you wouldn't have to run through trial and error testing to figure out what the setting for a given system should be but for the time being it is was it is.

This is why I gave up on my 396T years ago and became a GRE user. GRE just worked without tweaking.

Fingers crossed that Whistler will continue that works out of the box "tradition".
 

baybum

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Jan 19, 2003
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Howard County
It's very discouraging to see how they advertise these FIVE hundred dollar scanners as being so user-friendly and dummy-proof.

"Very simple to operate, you can be up and running in 3 minutes or less. No programming needed, just your zip code."

Then when you get it, you have to do all this tweaking and fine tuning.
Imagine if you had to do that with different TV channels on your new $500 TV??

I've never had to do any of this stuff with my "old" PRO-96 and it still works great.

Do these companies offer a "no questions asked" 60-day return policy?
They should.
 

redburgundy

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I am still not sure why leaving the 426's P25 Threshold Mode in the Auto configuration isn't working

I thought that Montgomery County is not an APCO P25 system.
If that's the case, why does a change to the P25 threshold have any impact?
 

redburgundy

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Messages
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It's still P25 digital voice....

It's sort of the other way around. There are several digital trunking systems, including APCO P25, that use the IMBE voice coder.
Are you claiming that the P25 Threshold setting relates to the IMBE voice coding, but does not relate to the P25 modulation (C4FM or CQPSK)?
 

dwlipp

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Messages
74
Location
Montgomery County, MD
RE: BCD436HP Montgomery County Tweaks

I thought that Montgomery County is not an APCO P25 system.
If that's the case, why does a change to the P25 threshold have any impact?

Motorola Astro (not Astro 25) trunked systems use the P25 CAI (common air interface) for voice and the Motorola Type II trunking protocol for control; as a result tweaking the P25 configuration in the scanner does impact the scanner's performance when monitoring these systems. Motorola Astro 25 systems use the P25 CAI and the P25 trunking protocol for control, so they are full P25 systems.

The Astro systems essentially come in two flavors, 3.0 and 4.1, which indicates what kind of controller hardware is in use but the trunking protocol and the P25 CAI are the same in either case, just the hardware that hosts the controller is different; Montgomery's system is an Astro 3.0 system.

Astro 25 system have a bunch of different flavors too that indicate what type of hardware is hosting the system and they can be using P25 FDMA, TDMA, or Motorola's proprietary X2, air interfaces but all use the P25 trunking protocol for control.

This is all a bit confusing for those that aren't immersed in it given the industry terminology and Motorola's branding of that terminology. I often see posts from folks who are confused that systems that aren't "P25" are using P25 modulation.

Hope this helps.
 

badlans

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Placitas NM
Motorola Astro (not Astro 25) trunked systems use the P25 CAI (common air interface) for voice and the Motorola Type II trunking protocol for control; as a result tweaking the P25 configuration in the scanner does impact the scanner's performance when monitoring these systems. Motorola Astro 25 systems use the P25 CAI and the P25 trunking protocol for control, so they are full P25 systems.

The Astro systems essentially come in two flavors, 3.0 and 4.1, which indicates what kind of controller hardware is in use but the trunking protocol and the P25 CAI are the same in either case, just the hardware that hosts the controller is different; Montgomery's system is an Astro 3.0 system.

Astro 25 system have a bunch of different flavors too that indicate what type of hardware is hosting the system and they can be using P25 FDMA, TDMA, or Motorola's proprietary X2, air interfaces but all use the P25 trunking protocol for control.

This is all a bit confusing for those that aren't immersed in it given the industry terminology and Motorola's branding of that terminology. I often see posts from folks who are confused that systems that aren't "P25" are using P25 modulation.

Hope this helps.
Wow! Great info. Excellent description. I use a RadioShack Pro-18, and it seems to work very well. Much appreciated, Capt!
 
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rdballenger

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Joined
Dec 19, 2004
Messages
39
Just across the river in Alexandria VA (I just posted a new thread), with a 536. This looks like a great forum - I'm glad to be able to join.

Regards,


David
KU8V
 

MacGnG

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Dec 8, 2013
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MD, USA
I had jury duty today in baltimore city. I didn't pick up anything from the courthouse on my scanner. anyone know what frequencies the courthouse uses?
 

maus92

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Jun 23, 2004
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The OP
Since I have had my 436 I have been somewhat disappointed with its performance decoding Montgomery's system, however, I think I may be cracking the code now. Here are the tweaks I have made as compared to an 'out of the box' configuration.

Firmware - 1.03.00
Squelch - 2

Under Options in the Site:
Modulation - FM
P25 Threshold - 11
P25 Threshold Mode - Manual

I am not sure whether the firmware update has really impacted the decoding performance or not, or whether the improvement is just the cumulative impact of the other tweaks, but at this point the 436 is matching (or maybe even ever so slightly doing better than) my 396XT when decoding the Montgomery system. Prior to these tweaks I was consistently getting choppy audio from the 436 with decoding error rates in the ~55-65 range (viewed in P25 adjustment mode; page 59 of the Owner's Manual). With these changes in place the audio actually sounds quite good and the error rates are in the ~15-25 range tracking with my 396XT sitting right beside it, or even doing a bit better from time to time.

I am still not sure why leaving the 426's P25 Threshold Mode in the Auto configuration isn't working the same way as the 396XT where the level quickly adjusts from the default level of 8 to an optimal level of 11, but I can live with things the way they are now. It would be better if the Auto mode actually worked automatically as it does in the 396XT so you wouldn't have to run through trial and error testing to figure out what the setting for a given system should be but for the time being it is what it is.

I was up in Gaithersburg at the airpark last night and listened to the Astro MC TRS for the first time using my 436. I have to say that the audio quality using this radio is poor - even after making 2 of the adjustments: P25 Threshold changed from 8 to 11; P25 Threshold Mode to Manual. I was unable to get a change to NFM to FM to stick: the window still showed NFM in the display. I'll need more quality time with the manual it seems.

Contrast this to the P-25 Phase II PG TRS, which came in extremely clear (for a digital system on a scanner) with no tweaks as I travelled down I-95 through Laurel, around the east side of I-495, and eastbound on US50 until the signal degraded between US301 and MD424. I was very impressed.

I have heard that Montgomery County is seeking a $25M upgrade to its system at some point. Are they considering going to Phase II P25?
 
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