Supposedly only one end will do. I've got some sites with both and some with one end. I can't see any difference so far. marlon
----- Original Message ----- From: "RickG" <rgunder...@gmail.com> To: "WISPA General List" <wireless@wispa.org> Sent: Wednesday, May 13, 2009 7:42 PM Subject: Re: [WISPA] Noise by me on a tower I've got my beads! Should I put them on both end of the cable? -RickG On Wed, Apr 29, 2009 at 11:27 AM, Marlon K. Schafer <o...@odessaoffice.com> wrote: > Yeah, the beads are amazing! We're starting to use them on almost all > tower > installs. > > Supposed to help with lightning too. Though we've not had enough of that > around here for a couple of years to really be able to see any difference. > > The worst part about the beads is getting the right ones! I'm still not > sure we're using the right stuff. sigh Ours are big enough that we can > (and do) wrap the cat 5 through them 3 turns. More turns is supposed to be > better. Whatever it is, they've REALLY cleaned things up at my FM radio > station site! Our customer compliant calls have dropped by 80 to 90% out > there! Wish I'd have really understood what was happening out there 4 or 5 > years ago when the new station went online. I always thought I was ONLY > fighting the massive amounts of 2.4 gig interference in the area. That's > still a problem, but much more easily dealt with than I'd ever have > imagined. > > marlon > > ----- Original Message ----- > From: "Eje Gustafsson" <e...@wisp-router.com> > To: "'WISPA General List'" <wireless@wispa.org> > Sent: Wednesday, April 29, 2009 8:10 AM > Subject: Re: [WISPA] Noise by me on a tower > > >> Ethernet crystal harmonics. The crystal on Ethernet is 25MHz. So your >> hitting them with the 9th harmonics. This bleeding is worst with PoE >> powered >> devices because it couples into the DC power over the cat5 cabling and if >> the power supply is not nice and clean it will couple into the AC system >> as >> well. I have been involved in certifying 4 radios in a FCC certification >> lab. Each time we ran into this problem especially when powered by PoE. A >> different power supply could make a huge difference but also installing >> ferried beads on the cat5 cabling (close to the radio port, directly >> after >> the poe device out port and directly on the poe data in port) cleaned up >> this emission. Using shielded cable will help on equipment that is >> picking >> up this radiated signal directly from the cat5 cabling but if it's bad >> enough and the powersupply isn't good enough the harmonics signal will go >> out into the AC source unless ferried beads been installed properly. >> >> On one of these devices I helped getting certified we had to make it >> mandatory to have these beads installed to be able to pass (product never >> made it to market). >> >> / Eje >> CTO >> WISP-Router, Inc. >> >> -----Original Message----- >> From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On >> Behalf Of Steve Barnes >> Sent: Wednesday, April 29, 2009 10:02 AM >> To: WISPA General List >> Subject: [WISPA] Noise by me on a tower >> >> 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/ > -------------------------------------------------------------------------------- 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/
