My Results on the Detroit System

feinstei · #1 (**permalink**) 10-16-2005, 06:34 PM

I took my Pro96 (firmware v1.3,) down to the corner of Livernois and Michigan on my way to visit my priest today. The Pro96 does just fine when in the center of Detroit. In contrast, travelling down the Lodge through Detroit gave lousy results however from 8 Mile to the 94/Lodge junction. The "State Police" trunking system worked much better in the car during this trip down the Lodge, receiving clearly both from the Detroit tower and the Northville tower.

When the fire at the factory at Buchanan near Livernois began this afternoon, all of the communications seemed to be received okay at my location at Michigan and Livernois. I did notice some "stop-start" choppiness in the transmissions however, so the DSP code may need some tweaking by Radio Shack. However, the reception and trunking were smooth and not cut off with bursts of white noice.

At my home in Oak Park (near 10 Mile and Greenfield), the situation is much worse. I suffer from all of the same symptoms that other folks on the board seem to suffer from. It just seems that the Detroit repeater system stinks and is not receivable, even in the inner ring suburbs.

As and aside, I used to notice, in the old Motorola Type I analogue trunking system used by the Detroit utilities that the signal was also rotten in Oak Park. I had to place the PRO-96 near a certain window in order to receive the control channel. The new system seems to suffer from the same rotten coverage. I wonder if they're using the same tower sites for the new system as that old Type I system.

It would be helpful if someone involved in the digital software decoding from Radio Shack would examine the characteristics of the Detroit system and see if there's some possible DSP change possible. I know that Uniden's latest scanner suffers from the same problems as the Pro96, but I think it may be a combination of poor repeaters and some minor problem with the Radio Shack and Uniden DSP decoding.

toydriver_det · #2 (**permalink**) 10-16-2005, 07:26 PM

Great work Feinstei! That answers some questions and brings up new ones.
Did it seem like the fire dept was handling the 5 alarmer ok, as far as radio comms is concerned?

Alpha432 · #3 (**permalink**) 10-16-2005, 08:26 PM

From where I live in Allen Park, I can get Detroit EMS and Detroit PD very well, or I should say a lot better than I recieve Detroit Fire.DFE only is the same choppy hit miss reception. I wonder why this is?

rdale · #4 (**permalink**) 10-16-2005, 10:27 PM

Just random occurrences...

Alpha1906 · #5 (**permalink**) 10-17-2005, 10:13 AM

I too live at 10 Mile and Greenfield and have monitored the DFD for years. On the old analog system, I got pretty good transmission on my Motorola Minitor, with occasional loss of signal. Needless to say, with this PR0 96, I get crappy reception, choppy transmissions and an overall crappy experience.

feinstei · #6 (**permalink**) 10-17-2005, 02:40 PM

Again, I really think that the they must have used some new digital encoding firmware on the Detroit system only (the Michigan State Police towers from Detroit and Northville are perfectly receivable) that the firmware engineers who did the Pro96 and Uniden digital didn't code for.

If I ignore "trunking" and just program in all of the frequencies (except the control channel) from "Site 701" and conventionaly scan them, there is STILL no happiness. The audio chops off and degenerates into blasts of white noise etc. Thus, it is clear that the digital decoding software on the Pro96 and the Uniden are not equipped to handle the modifications in the digital signal that were implemented on the Detroit system.

I have listened to the radios that the Detroit EMS teams are equipped with (I am friends with one of them) and there is NO problem with coverage or reception, even at 12 Mile and Woodward in Berkley.

My results on Sunday, listening at the corner of Michigan and Livernois, had some problems, although the strong signal strength ameliorated some of them and I was able to receive complete transmissions without the degradation into white noise blasts.

Despite having better results in the city than in Oak Park, I believe that it is incumbent on Radio Shack and Uniden to research any recent digital decoding firmware changes made by Motorola to their radios and implement these changes in the DSP of their scanners. It's my belief that no "firmware" changes would be necessary, but only downloadable changes to the DSP such as was done previously on the Pro96.

jsmeed · #7 (**permalink**) 10-17-2005, 02:48 PM

Feinsti seems to have gotten the same results as I did last week (posted on another thread). I live in Dearborn and get hit and miss reception, but once in Southwest Detroit, it seems rock solid.

Is it possible that the scanner is being "confused" by receiving more than one tower at a time? How do the Moto radios lock onto one tower if they are in between two of them?

Thunderbolt · #8 (**permalink**) 10-17-2005, 04:24 PM

Quote:

Originally Posted by feinstei

Again, I really think that the they must have used some new digital encoding firmware on the Detroit system only (the Michigan State Police towers from Detroit and Northville are perfectly receivable) that the firmware engineers who did the Pro96 and Uniden digital didn't code for.

I really have to believe that this is the case, because a friend of mine recently played with a DFD portable radios and it receives the system loud and clear throughout Dearborn, Ecorse, and Livonia. Therefore, I have to believe GRE and Uniden need to catchup in the audio firmware dept. The sooner the better!

rdale · #9 (**permalink**) 10-17-2005, 07:20 PM

"I really think that the they must have used some new digital encoding firmware on the Detroit system only "

Actually this is the same problem that has plagued the Monroe Co subsystem since it came online too... And I don't have a lot of time spent around Flint, but reception is sub-par on the Genesee Co subsystem. So I don't think this is Detroit-only.

toydriver_det · #10 (**permalink**) 10-17-2005, 10:12 PM

Quote:

Originally Posted by jsmeed

Feinsti seems to have gotten the same results as I did last week (posted on another thread). I live in Dearborn and get hit and miss reception, but once in Southwest Detroit, it seems rock solid.

Is it possible that the scanner is being "confused" by receiving more than one tower at a time? How do the Moto radios lock onto one tower if they are in between two of them?

Took a trip downtown tonight to watch the Redwings beat San Jose and I did notice that I got a lot better, if not perfect, reception south of 8 mile on I-75. Don't know what that means but for what it's worth

Let's Go Redwings

brianw83 · #11 (**permalink**) 10-18-2005, 10:07 PM

Quote:

Originally Posted by rdale

" And I don't have a lot of time spent around Flint, but reception is sub-par on the Genesee Co subsystem. So I don't think this is Detroit-only.

I'd be inclined to agree with you. Ive passed through Genesee many times too this summer via I-75 and very rarely have picked up on Genesee county TG's. Pick up plenty of MSP, but not Genesee.