996T 800 full signal broken reception

[Anderegg]

I am trying to figure out why a 996T is getting horrible reception on the San Diego RCS system. It's an 800 simulcast system, and it was suffering low signal/broken reception due to an old VHF roof antenna install. After installing a new 800 antenna, the signal meter reads full, with an RSSI of around 500-600 on the control channel. When logging hits with FreeSCAN, I get like RSSI of like 300 on many channels, and even though the radio shows full bars, I get extremely broken P25, and scratchy analog that breaks in and out of squelch.

It's not a "too much signal" issue with the P25, as the analog stuff is all static and broken as well. My question is this......does the signal strength meter show the current receiving frequency of the active talkgroup, or is it always the control channel?

The weird thing is when I hooked up my 396XT on the same antenna/cable/etc, it gets the same signal strength, but the reception is MUCH BETTER, not breaking in and out. Also, when using my on scanner antenna indoors, the signal will be like 1 bar, but I still get unbroken reception, even though the 996T next to it is full signal and broken. Can scanners go bad with age? The attenuator is not active, checking all the menu options, can't figure this problem out.

This problem exists on the LOWEST signal 800 system being monitored, the other two get MUCH BETTER RSSI and signal, and do not suffer any choppy reception or simulcast digital breakup.

Paul

 

[Dewey]

This wouldn't address that signal being scratchy, but are you sure that the "broken" signal is not the sampling by one of the priorities?

Dewey

 

[Anderegg]

No priority in the scanners. I checked the firmware, and the scanner (actually there are a few of them!) are like 1.02.11, I think that's the original 2005 version! Will update the firmware, and see if that fixes the digital breakup a little bit......I know that won't solve the reception fading in and out, but it is worth a shot.

Paul

 

[Dewey]

No priority in the scanners.
...

Paul

It looks like you are saying that you don't have any channels programmed as priority. However, if you are not already aware, Weather and Close Call operate as priorities as well and create the same break about every two seconds during reception. If you already knew this, my apologies.

Dewey

 

[Anderegg]

Those are shut off.....the breaking and loosing signal sounds like the (analog) signal is at the verge of reception range, cutting in and out, but the signal meter shows full strength.

On my new 996XT's, I get this cool thing where I get full signal that flashes to no bars every second or so....also not priority, i think it is an issue with simulcast sites and the scanner getting confused....brand new scanners, new firmware, ugh.

paul

 

[Dewey]

Sorry, but I've reached my limitation on this one if all of the priorities are turned off. The only and final thing that I would add is that if it is predictable like every second as you say and not random, it certainly seems to be man made (like the priorities) rather than signal fluctuation.

Dewey

 

[UPMan]

If you are simply monitoring a control channel, you'll see the signal bar drop every 1-2 seconds. That is when the scanner does some "housekeeping". If you want that drop to take longer to occur (or if you just want to verify that is the reason for the behavior) set the site hold time to 10 seconds...the "drop" should change to occuring every 10 seconds.

 

[Techy]

I get the same with my BCT15X. Full signal, but choppy and a scratchy signal at times. Im sure it's due to being within 3 of the TRS's 6 site simulcast system. Im very close to 3 of the sites towers.
Must be multipath distortion or something. In the summer when the trees are in bloom it gets rather bad. But now no trees with leaves, it's alot better. But Paul! I saw that signature note there and fell over LOL. I got my fingers crossed!

 

[UPMan]

You won't get broken /choppy/scratchy on an analog system due to simulcast. Instead, you might possibly hear some odd audio artifacts occasionally. In your situation, I'd first try attenuation or other methods of reducing the overall signal input (sounds more like desense issues).

Of course, also make sure the noise isn't what is being transmitted by the site. On an analog system, a unit trying to communicate from a weak-signal location will sound like that going into the repeater...and will get repeated that way.

 

[Techy]

Paul, this is how it sounded during the summer. Very choppy with a bad signal. The antenna and every aspect is brand new. Antenna is above the roof line. Im very near 3 of the towers within say 10-15 miles. One North and 2 Southerly locations.

BCT15X Issue- Simulcast Distortion? - YouTube

 

[Techy]

Forgot to add yesterday, with the ATT on, I loose the control channel. The same results are with an indoor antenna as well. And that is the RS 800 Mhz. duck. Same results on the GRE scanners.

 

[Anderegg]

Signature note?

The link you posted is very similar to the reception issues I am experiencing, except imagine the signal meter going higher and lower, with the transmission dropping squelch at the low "dips". I just updated to the newest firmware this morning, will be seeing if this improves the situation at all. If things stay the same, I will pull a 996XT out of my car and install it in place of the 996T and see if the gosh darn XT or the newer radios are simply better at receiving than the old ones!

Paul

 

[UPMan]

Your other description (better in the Winter than in the Summer) is also typical of reception issues. Leaves/foliage are heavier in the Summer, reducing the signal propogation. When all those little biological attenuators fall to the ground, signal quality improves.

 

[Anderegg]

hey Paul, while you are hear, if I swap in a 996XT in place of the 996T, do you think my reception would improve? When I attach my 396XT to the same antenna (outdoor on a roof) it does not loose signal (no squelch break) totally on analog, and the digital seems to not be as choppy, probably the same reception issue.

I will be swapping in a new 996XT for testing in the future, but wanted to know if you had a quicky answer........just asking cuz am waiting to purchase 3 or 6 996XT's depending on if they fix this reception issue! Thanks!

The other Paul

 

[UPMan]

Without knowing why the T is no receiving well, that is hard to say. But, since you are havng success with the 396XT, I suspect so.

 

[Anderegg]

After I swap out the T for the XT and test reception, I will post an update.

Paul