Interference from cellphone towers

[far342]

Sorry if this isn't the right place to post this thread. There are about 3 spots in my city with cell towers that block the signal of a 700mhz trunked system I monitor. I get up to maybe 1200 feet away from any one of the towers and the control channel signal just drops completely. It happens on my 436 with my vhf antenna and my 700-900 mhz antenna. This also occurs with my friend's sds100 & 200. Is there any way to fix this? I have yet to play around with filters as I don't yet own an sds.

These are the sites we monitor that this occurs with: Site 1, Site 2

 

[kayn1n32008]

Additional filtering to attenuate the cellular base station transmitters.

 

[CollinsURG]

Unfortunately filtering cellular will be virtually impossible as there are cellular frequencies throughout 600 to 900 Mhz all within the 700/800 Mhz public safety bands.

I have an SDS100 and it is very prone to being saturated by cellular transmissions when very near cell towers which shuts down reception. It is a weakness due to the use of the Rafael TV chips used in the RF front-end of the SDS100 and SDS200. I rarely have issues of this with the BCD325P2 and HP2. The first time It happened with my SDS100 I thought something was wrong with it, then I noticed a cell tower about 500 feet away. There is hope that Uniden has addressed this with the RF design of the new SDS150. Time will tell once enough units are in the hands of users.