To me, two things appear possible. 1) That you are likely running a non-FCC certified system :-( 2) Noisy DC power circuitry on SBC, remember the MT 532 (DC power) problem 2 years back?
I'd suggest that you hire the guy that found the noise in the first place, and take the analyzer to each SBC, and find out which SBC is causing it. Of course its not guaranteed to be the SBC, but I'd think that first. Note putting it in a metal case does not always fix the problem, and sometimes can make it worse. For example withthe 532 problem, two years ago, put in a PacWireless case, there was half the noise if I took the cover off. (Which is why SBC need to be certified with the case they are installed in.) If the RB600 or 411 is generating nise like that, I'm sure we'll all want to know about it. Let us know what you find. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband ----- Original Message ----- From: "John Scrivner" <j...@scrivner.com> To: "WISPA General List" <wireless@wispa.org> Sent: Sunday, May 10, 2009 11:54 AM Subject: Re: [WISPA] Noise by me on a tower Shielded Cat 5 and Ferrite Beads are your friend. I have been where you are and this fixed it all for me. Scriv On Wed, Apr 29, 2009 at 10:01 AM, Steve Barnes <st...@pcswin.com> wrote: > I have an odd situation, I have 2-2.4 180* sectors MT RB411 and 5-5.8 > StarOS War1 backhaul radios and a RB600 router at the top of a 265ft old > AT&T microwave tower. The top has a grounded NEMA metal box and POE > powered by an Allen Bradley converter. I have an AC and an Ethernet run to > the base where I have a APC UPS. > > The owner just leased space to another client 20 Feet away on same level > from me. It is a local REMC doing meter reading on 221Mhz. They were > having problems with receiving they brought in a spectrum analyzer and > there was a noise floor of -71 at 220Mhz. The tower owner being an radio > guy not a wireless guy just killed power on the ups. (taking down all my > stuff and locking up 1 one of the radios for an hour GRRR) When our > equipment was off the noise floor went to -108. As soon as he powered me > back up the noise returned. They actually said that there was noise from > around 150Mhz to 240Mhz. > > Everything is grounded and cased in metal except the LMR that goes to the > Antennas, the AC wire is in flex and the shielded Ethernet down the tower. > > Ideas? there might be a little noise off the oscillators of the War-1 > boards but that's 175Mhz. The Ethernet is 100Mhz, RB411 300Mhz and RB600 > 266 MHz > > Steve Barnes > RCWiFi Wireless Internet Service > > > > -------------------------------------------------------------------------------- > WISPA Wants You! Join today! > http://signup.wispa.org/ > -------------------------------------------------------------------------------- > > WISPA Wireless List: wireless@wispa.org > > Subscribe/Unsubscribe: > http://lists.wispa.org/mailman/listinfo/wireless > > Archives: http://lists.wispa.org/pipermail/wireless/ > -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
