Chester County 159.600 MotoTRBO interference

[benrussellpa]

Just taking a quick survey to see who is getting interference on 159.600.

I started hearing MotoTRBO noise on the frequency this weekend on my county pager, scanners, and commercial radios that I own. Looking through the FCC licenses, I discovered that the North Penn SD (in Montco) has a license with 159.600 as an output with an emission designator indicating MotoTRBO.

ULS License - Industrial/Business Pool, Conventional License - WPHG723 - NORTH PENN SCHOOL DISTRICT

The effective date for the most recent changes is 11/9/12.

Since I live outside Chester County, I don't know that this would be considered harmful interference, but I also don't know if this is extending down into Tredyffrin, Schuylkill, and Phoenixville areas. Anyone else hearing this from *inside* Chester County? If you're with a fire company or other county organization, is it interfering with your pagers?

[baycomm]

There has been A LOT of controversy regarding the use of MotoTRBO on VHF public safety frequencies. Due to the lack of defined repeater splits combined with the nature of TRBO emissions the FCC is moving toward making it very difficult to use TRBO on VHF public safety channels.

This is information from one of the trade groups that I belong to:
Following a meeting with the FCC and manufacturers, the PSCC has proposed the following
coordination standards for VHF public safety digital applications:
Digital and Analog System Compatibility
1) 250 km protection from proposed base station to co-channel and 7.5 kHz adjacent
channel incumbent mobile licensees;
2) Assume incumbent mobile receiver antenna height equal to transmitter antenna
height;
3) If receiver antenna cannot be inferred from (2) above, assume a 60 m receiver
antenna;
4) Perform Longley-Rice study at 50% (time), 50% (location), and 50% (probability)
for proposed digital systems; and
5) A signal level of -110 dBm or greater at incumbent site will cause proposed station
to fail the protection standard.
It is anticipated that this latest proposal will be contested by one or more
manufacturers as this policy effectively precludes any further deployment of
digital technologies in the public safety VHF band; and essentially provides
exclusive frequency status to incumbent analog users in the shared VHF bands.
It is also possible that the economic issue of requiring applicants to invest in the
added time and expense of such detailed spectrum analyses with the likelihood
of being routinely advised that no frequencies are available may also be raised
with the FCC.

I suggest that you speak to someone at the county, the reliability of their fire paging is very important.
I'm sure that they will want to know what's going on.

I'm not a TRBO fan primarily due to the potential that it has for producing interference along with the inefficiency of taking up a full 12.5 Khz channel even if the users never needs to use both time slots. NXDN on the other hand does not have these problems

I'm actually not far from you, PM me if you want to discuss this further. I'll take some quick signal strength readings next time I'm in the Main Line area.

[jjimenez01]

Ben,
I can hear the Mototrbo signal loud and clear in King of Prussia and in Wayne. I have alerted the Main Line Chiefs Association about this problem. They will be following up with Chester County DES asap.

JJ

[benrussellpa]

I definitely reported this through official channels. Just though I would check here to see how far out the issue extends. Since I live outside the county and closer to the likely source of the problem, I didn't know if this was just an issue for me or not. I had to go to Phoenixville this weekend and took 23 past Valley Forge Fire Co to confirm that it can be heard on pagers near there, so that would be a problem inside Chester County. JJ, I figured you'd see this and be all over it, too...looks like it does get down your way. I wasn't sure it would. The signal seemed to drop off pretty quickly while I was mobile on Sunday.


Hopefully, this will be resolved.

[jjimenez01]

I received an email that volunteers in West Chester are getting it loud and clear there. The email chain has started between fire chiefs, politicians and DES officials.

Ben, thanks for pointing this out. I can't believe some coordinator thought this would be a good idea.

JJ

[hippieman556]

I get it here in willow grove

[benrussellpa]

JJ,

I just submitted info again today on where I can still hear the interference (202 as far south as Cedar Hollow Rd and then again around Boot Rd on the pager inside my work truck). Apparently, FCC advised the school district to reduce transmitter power. If that fails to resolve the issue, further steps may be taken. Let all your contacts know to keep an ear on the channel and report any continued interference to the county.

[jjimenez01]

Thanks for the update Ben. Your message has been passed on.

JJ

[DEPUTY11]

loud and clear up north in chesco still

[maxim5522]

I AM GETTING IT HERE IN THE HOLE TOO,, UNREAL!! How can the fcc let this happen ...what a bunch of yahoos the fcc are for real ..

[baycomm]

Don't blame the FCC. It's up to the dealer that sold it to them to properly engineer the system. Too many of the radio dealers no longer have the technical expertise to do so. Their entire objective is to meet sales quotas. The end result is irrelevant to them.

[DEPUTY11]

loud and clear up north in chesco still

[KB3WIR]

Still loud and clear up here in Northern Chester County. Everywhere from Morgantown down through Downingtown and Exton. It's annoying as heck, and 90% of the time I get fed up with it and shut the scanner off. I work in Westtown and I even hear it at work from time to time.

[benrussellpa]

Originally Posted by KB3WIR

Still loud and clear up here in Northern Chester County. Everywhere from Morgantown down through Downingtown and Exton. It's annoying as heck, and 90% of the time I get fed up with it and shut the scanner off. I work in Westtown and I even hear it at work from time to time.

Unfortunately, the FCC does not care if it interferes with reception on scanners or VHF radios.

Only if it interferes with reception on the pagers themselves will they accept the complaints as valid.

Power was reduced on the TRBO transmitter based on earlier pager interference that was documented and reported to county.

However, unless more complaints of interference received *on pagers* is reported to county and then to the FCC, nothing will likely change.

I have the VHF channels programmed in my VHF mobile in my work truck and I can pick that TRBO signal up on the turnpike almost to the Lebanon/Lancaster exit. I rarely listen to 159.600 anymore on radios and scanners...only at night when the school radio traffic is almost nil.

[jjimenez01]

Additional correspondence as been sent to a number of chief officers within Chester County. I have also urged all chiefs or their designee's to submit trouble tickets on the counties Enterprise Wizard web site. If you have credentials to submit tickets please do so.

https://chestercounty.enterprisewiza...esterlogin.htm

JJ