Need extreme Nextel adjacent ch rejection

[AZDon]

I have a home in St Clair Shores MI. St Clair Shores PD operates on a macomb county simulcast system run by the state of Michigan.

My HP 2 is receiving interference from a Nextel tower located about 1/2 mile south of me.
The closest Macomb county simulast site is 2 miles directly north of me. A yagi antenna was not enough to reject some of the Nextel adjacent ch interference occurring on some of the state simulcast system. Thinking about making an antenna in a can to reject or reduce Nextel signals from the site south of menwhile directingbthe open end of the can to the north towards the simulcast tower. Anyone have any ideas? FYI, tried using different rubber ducky antennas in the house, Nextel interference is present on many of the simulcast transmissions but not all of them. Need some help here guys, your thoughts?

 

[Ubbe]

Did you try a variable attenuater to reduce the level until the nextel signal stopped interfering?
As you have a yagi the signal from the simulcast system are probable sufficient anyhow.

/Ubbe

 

[AZDon]

Interference

have not tried that yet, looking for a good one any ideas?

 

[JamesO]

"T" stub filter??

CATV variable attenuators are reasonably cheap,

https://www.amazon.com/Konig-Variab...505818423&sr=8-1&keywords=variable+attenuator

Not sure what shipping would be from this supplier - https://www.solidsignal.com/pview.a...cBBkjp-marQ7SH3vWjLBolSAxSVxxUGMaArZTEALw_wcB

 

[AZDon]

Nextel

The HP2 has a built in antenuator seems to be too strong, will try a variable one.

 

[JamesO]

The HP2 has a built in antenuator seems to be too strong, will try a variable one.

Yes, this is the problem, usually 3-6 dB is all you may need, more than that you start to kill the singles you are trying to receive. A stub "T" filer may be something to consider as well, but this takes some experimenting.

 

[AZDon]

SMA Attenuator

Purcased a 3db and a 6db SMA anttenuators from Hasco Inc. Hoefully one or both of these will do the job.

 

[iMONITOR]

I have a home in St Clair Shores MI. St Clair Shores PD operates on a macomb county simulcast system run by the state of Michigan.

My HP 2 is receiving interference from a Nextel tower located about 1/2 mile south of me.
The closest Macomb county simulast site is 2 miles directly north of me. A yagi antenna was not enough to reject some of the Nextel adjacent ch interference occurring on some of the state simulcast system. Thinking about making an antenna in a can to reject or reduce Nextel signals from the site south of menwhile directingbthe open end of the can to the north towards the simulcast tower. Anyone have any ideas? FYI, tried using different rubber ducky antennas in the house, Nextel interference is present on many of the simulcast transmissions but not all of them. Need some help here guys, your thoughts?

Are you certain it's 'NEXTEL'?

In late 2010, Sprint Nextel announced plans to decommission the Nextel iDEN network; on May 30, 2012, Sprint Nextel announced that it would shut down the Nextel network as early as June 2013.[4] The Nextel network was officially shut down at 12:01am on June 30, 2013 and Sprint is currently deploying LTE equipment on the 800 MHz spectrum formerly used by the iDEN network.
[source]
https://en.wikipedia.org/wiki/Nextel_Communications

 

[tdeater]

I have read a lot of posts about issues monitoring simulcast systems, I wounder if maybe the noise you are hearing is related to the issues with some scanners picking up simulcast systems. I have no idea though that that would sound like, we don't have anything simulcast on this side of the state that I have tried to monitor. Nextel has been pretty much gone for quite a while now, but there are some IDEN carriers still scattered around here and there.

 

[AZDon]

Nextel

Good point but a sign on the tower in question says Nextel, Next time I go back to MI I will bring a spectrum analyzer to get a better idea what is going on. In the mean time I am waiting for the anteuators to arrive.

 

[iMONITOR]

My HP 2 is receiving interference from a Nextel tower located about 1/2 mile south of me.

When you say 'interference', exactly what are you hearing? Just digital noise, 'Donald Duck' sounding voice distortion? Are you not able to hear the Macomb's talk groups on MPSCS at all? Have you tried minimizing your antenna? Try using a piece of wire about one inch poked into the center of the BNC connector.

I monitor the same system here in Macomb. I used to have a very difficult time due to being close to about four of the antenna sites causing multiplexing from the simulcast system. The smaller the antenna the better, in my case.

Have you tried to take the scanner in your vehicle, and monitor from another location. Did you program just the control channel frequency, or the voice ones as well?

 

[mmckenna]

Good point but a sign on the tower in question says Nextel, Next time I go back to MI I will bring a spectrum analyzer to get a better idea what is going on. In the mean time I am waiting for the anteuators to arrive.

That just means that Sprint never replaced the sign. I've got a Nextel hut at one of my tower sites, but it's full of Sprint equipment. They just never got around to putting a new sign on the door.

Sprint took over the Nextel licenses and uses that spectrum for their cellular service. No more IDEN, though. While they are using the old Nextel 800MHz frequencies, they are still removed from the LMR stuff by a few MHz. At your distance from the site, and the frequency offset, I think it would be unlikely it's causing near channel interference. Could be receiver overload on your end, but I think it's the simulcast distortion as tdeater mentioned. The 800MHz rebanding is keeping things separate. If they are that close in frequency, someone is operating outside their license. Either Sprint didn't move or the agency didn't move.

 

[AZDon]

Nextel

The tower in question has a Nextel sign on it. Spectrum analyzer indicates frequencies that were licensed to Nextel. A yagi antenna pointed at the site then away suggest that the offending site is the question in tower. The problem began when the tower in question went into service. Hopeful that the signal strength from the desired source is stronger than the offending site. Nearly half of the frequencies used by the simulcast
System are being interfered with to the point that they can hardly be understood. A antenuator might work. Relocating the scanner about 1/2 mile closer to the desired site happens to be 1/2 a mile further from the offending site yields clear transmissions.

 

[AZDon]

Adjacent Nextel

Found a nice little SMA 3db antenuator, worked well.