SDS200 This is what cell phone tower interference looks like.

Anderegg

Enter text in this field
Premium Subscriber
Joined
Mar 7, 2010
Messages
2,226
Location
San Diego
Parked at my station under our parking lot mounted 100 foot cell tower...the local city 700MHz LSM Phase 1 trunking system coming in at an amazing -30dBm, with digital errors as high as 50. Thank you 4G. :-|

20201021_215307.jpg
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
5,126
Location
Stockholm, Sweden
You will probably not see that using other scanners than the SDS series. To get more or less perfect reception of simulcast systems you have to sacrifice other performancies in SDS scanners. The perfect scanner have not yet been produced.

/Ubbe
 

n1chu

Member
Premium Subscriber
Joined
Oct 18, 2002
Messages
845
Location
Farmington, Connecticut
I thought RSSI readings were inaccurate, at best unreliable? -30DBm is a nice reading but is it a true reflection of the actual signal you want, or other splurious entities in a high rf environment? And the error rate... how did that affect the ability to hear? Was it unreadable? (I’m running under the idea these two readings are “ballpark” values, possibly not all that much accurate?)
 

Anderegg

Enter text in this field
Premium Subscriber
Joined
Mar 7, 2010
Messages
2,226
Location
San Diego
This cell tower will fade an APX at our main gate, which is in the radiation beam path of a few of the arrays! The SDS was below and out of the beam, but still...4G is a *****.

Paul
 

kb5udf

Member
Premium Subscriber
Joined
Apr 7, 2004
Messages
578
Location
Louisiana
I wonder if you have the same issue I do in a few locations, First net down around 768 (give or take) and below). Giant wall-o-noise I can see on an SDR
 

R0am3r

Saltwater Conch
Premium Subscriber
Joined
Apr 13, 2014
Messages
336
Location
Oneida County, NY
You will probably not see that using other scanners than the SDS series. To get more or less perfect reception of simulcast systems you have to sacrifice other performancies in SDS scanners. The perfect scanner have not yet been produced.

/Ubbe
So only the SDS series radios are affected by cell tower transmissions while standing under the tower? Nice generalization.
 

R8000

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
747
So only the SDS series radios are affected by cell tower transmissions while standing under the tower? Nice generalization.
My Whistler 668 just gives up on 700-800 MHz when I am within a mile or so of a cell tower. I never connected the dots until I was trying to monitor a analog 800 MHz smartnet system and heard it with my own ears. The noise floor just rose until the point the thing just stopped receiving.
 
Top