Don't you document where your splices are? If you see your splices every 33k and see it's broken 1 mile from the last splice it should be pretty obvious, no?
On Tue, Aug 27, 2024 at 6:26 PM <[email protected]> wrote: > Magical device called a fusion splicer. Our reels were typically 33,000’ > > > *From:* Josh Luthman > *Sent:* Tuesday, August 27, 2024 3:51 PM > *To:* AnimalFarm Microwave Users Group > *Subject:* Re: [AFMUG] fiber patch cables > > I don't see how you have a 50 mile span. Even if you get 80k reels that's > 15 miles. > > On Tue, Aug 27, 2024 at 5:19 PM <[email protected]> wrote: > >> When you have spans up to 50-75 miles at times, you have to use longer >> high power pulses. There is a lot of variability in velocity of >> propagation, earth temperature, splice slack loops, fiber twist. 1 mile >> error over 50 miles is only 2%. You can easily be off by several thousand >> feet. You can’t just go dig. You have to go to the closest splice point >> and test again, even then if you it show the fault 2000 feet away and you >> dig at 2000 feet you may be off by 20 feet or more. I have been doing this >> for decades. Takes lots of digging to actually find it. >> >> *From:* Josh Luthman >> *Sent:* Tuesday, August 27, 2024 3:01 PM >> *To:* AnimalFarm Microwave Users Group >> *Subject:* Re: [AFMUG] fiber patch cables >> >> A mile?! IDK how that's possible. Every time we turn a new splitter on >> the sequentials and OTDR are within a few feet - we lose a couple of feet >> in butt splices and our sequentials end up wrong. Every new reel gets >> tested on delivery and it's right on. >> >> When we had a broken fiber (ants) it was right on the case. When we had >> a broken fiber (ribbon got knicked with installation) it was between two >> cases. >> >> On Tue, Aug 27, 2024 at 3:48 PM <[email protected]> wrote: >> >>> Wow, sometimes looking for gopher damager over 20 miles I have been off >>> a mile. >>> >>> >>> >>> *From:* Josh Luthman >>> *Sent:* Tuesday, August 27, 2024 1:30 PM >>> *To:* AnimalFarm Microwave Users Group >>> *Subject:* Re: [AFMUG] fiber patch cables >>> >>> So far every time we've used the OTDR it's been accurate within 1 foot. >>> >>> On Tue, Aug 27, 2024 at 12:55 PM Trey Scarborough <[email protected]> wrote: >>> >>>> The only thing you have to worry about with shorter cables is the >>>> reflection. In some instances with dirty connector at just the right >>>> connector you can get reflection back in to the transmitter that can cause >>>> errors, the tx to shut down or premature failure. This is very uncommon >>>> with LR 10G and less optics and can be prevented from making sure you have >>>> clean connectors. Check the RX and TX levels and make sure you don't have >>>> excessive loss. With 100G its a little different story due to the combined >>>> power of multiple channels, but still can be prevented by cleaning >>>> connectors, but in some instances Ive had to use attenuation when mixing >>>> different vendor optics. >>>> >>>> The using no launch on an OTDR most automatically calibrating OTDRs >>>> will work without one. Your results can be off though. Most of the lower >>>> cost ones are also lower powered and have less of an RX sensitivity so they >>>> don't suffer as much from the reflections interfering when testing. I can >>>> test all day long with my little otdrs without one, but my long range 200k+ >>>> units I have to have a minimum of a 1k spool on it or you see ghosts. They >>>> will show up as repeating events at even intervals. Not something you will >>>> see on shorter runs either. >>>> >>>> >>>> On 8/26/24 4:31 PM, Ken Hohhof wrote: >>>> >>>> I should note that apparently I used to do this with direct attach >>>> cables (DAC) but I think that was a pain, one more thing to stock and to >>>> bring with for projects. Whereas I’d always have boxes full of SFPs and >>>> fiber patch cords. >>>> >>>> >>>> >>>> *From:* AF mailto:[email protected] *On Behalf Of *Josh Luthman >>>> *Sent:* Monday, August 26, 2024 4:20 PM >>>> *To:* AnimalFarm Microwave Users Group mailto:[email protected] >>>> *Subject:* Re: [AFMUG] fiber patch cables >>>> >>>> >>>> >>>> People say you need a launch cable but our cheap china OTDRs have no >>>> issues seeing the connector at the end of the patch cable and stuff >>>> beyond. I bought a big launch cable back in the day and never use it >>>> anymore. >>>> >>>> >>>> >>>> Might be different with AE? >>>> >>>> >>>> >>>> On Mon, Aug 26, 2024 at 5:16 PM <[email protected]> wrote: >>>> >>>> Only minimum length I know of is the OTDR dead zone. If that is a >>>> problem you purposely lengthen the cable with a launch cable. >>>> >>>> >>>> >>>> *From:* Josh Luthman >>>> >>>> *Sent:* Monday, August 26, 2024 1:59 PM >>>> >>>> *To:* AnimalFarm Microwave Users Group >>>> >>>> *Subject:* Re: [AFMUG] fiber patch cables >>>> >>>> >>>> >>>> Reddit is wrong. Gasp. >>>> >>>> >>>> >>>> Connectors are loss, there is more loss in either one of the connectors >>>> than there is the single mode glass. >>>> >>>> >>>> >>>> Between a switch/router in a rack what I see all the time is long (like >>>> 5/10/15 feet) cables and then put the slack in a loop along the posts. >>>> >>>> >>>> >>>> On Mon, Aug 26, 2024 at 1:19 PM TJ Trout <[email protected]> wrote: >>>> >>>> Patchbox makes some great products, their fiber system is pretty slick >>>> but expensive. >>>> >>>> >>>> >>>> Cable length is irrelevant it's optical budget / Rx signal strength. >>>> Normally on 2-20k LR optics you are ok with any length cable, 40km+ needs a >>>> pad on short spans. (Attenuator) >>>> >>>> >>>> >>>> On Mon, Aug 26, 2024, 8:29 AM Ken Hohhof <[email protected]> wrote: >>>> >>>> Is there a minimum length for a single mode fiber patch cable? >>>> >>>> >>>> >>>> I have been using 1 meter cables and they are almost always too long, >>>> I’m talking about going between routers and switches in a rack, stuff like >>>> that. I see that FS sells 0.5 meter cables, but I saw somewhere like maybe >>>> on Reddit someone claiming there was a minimum length. Given SM fiber and >>>> LR optics, I don’t see how 0.5 or 1.0 meter would be different they are >>>> both essentially zero length. >>>> >>>> >>>> >>>> Probably there’s some kind of cable tray or cable management solution I >>>> could be using but I’ve never liked such things. >>>> >>>> -- >>>> AF mailing list >>>> [email protected] >>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>> >>>> -- >>>> AF mailing list >>>> [email protected] >>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>> >>>> ------------------------------ >>>> >>>> -- >>>> AF mailing list >>>> [email protected] >>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>> >>>> -- >>>> AF mailing list >>>> [email protected] >>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>> >>>> >>>> -- >>>> AF mailing list >>>> [email protected] >>>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>>> >>> ------------------------------ >>> -- >>> AF mailing list >>> [email protected] >>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>> -- >>> AF mailing list >>> [email protected] >>> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >>> >> ------------------------------ >> -- >> AF mailing list >> [email protected] >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> -- >> AF mailing list >> [email protected] >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> > ------------------------------ > -- > AF mailing list > [email protected] > http://af.afmug.com/mailman/listinfo/af_af.afmug.com > > -- > AF mailing list > [email protected] > http://af.afmug.com/mailman/listinfo/af_af.afmug.com >
-- AF mailing list [email protected] http://af.afmug.com/mailman/listinfo/af_af.afmug.com
