Has anyone tried THESE, THESE or any bandpass filters for 900mhz systems?
Most of my SR9’s are reporting noise floors worse than -80dBm. Just wondering if a bandpass filter would help any..
If anyone has any experiance with bandpass filters in general please let me know if they helped too..
Thanks,
Gerard
Stay away from the ones from Hyperlink, they are only 4 pole. If you look at the cutoff freq. you can see why I say stay away from them. Your trying to block out the lower pager band that starts at about 929 Mhz. The hyperlink filter does not roll off untill 1015Ghz. On the lower side you want to block the lower cell bands and 2 way radio 860-890 range, the hyperlink starts the roll off at 815. So you can see they don’t filter anything you need filtered.
RFLinks makes very good products, also Titan-wireless now has the Ubiquity filters for about $55 less. I have 3 coming in this week.
Hydro
Hydro,
Did your Ubiquiti filters come in? If so how did they work out? I have one coming tomorrow and I’ll post my results soon as I get it installed..
-Gerard
Sorry I took so long to post my results. I tested the CF912 on the bench and on a 50 ft tower at our office with the same results.. No improvement at all. My noise floor was in the upper 70’s when I started and its still in the upper 70’s.. I’ve tried 20,10, and 5 mhz channels..
I have a Pac Wireless 11dBi 900mhz Omni connected into one side of the CF912 and the other connects into a RB112 with a SR9 in it. I have tried 2 different SR9’s and I have verified the antenna is on the right connector.
What noise floors are other people getting with SR9’s?
-Gerard
-96 at 300’ in air.
You must have a bunch of noise there! I had -90@ 285’ with a 8dbi omni, but it would from time to time drop to -80. I installed a noise filter and it is stable at -95 now.
I had the same results with the Ubiquitti filter: -78 before, and -78 after…
SMA