On Wednesday, 21 March 2018 11:45:15 GMT Ralph Corderoy wrote: > https://en.wikipedia.org/wiki/Cat_5 might be of interest.
Yes. We saw that before we even attempted it. We always knew that the poor old Pi might not be man enough for the job, but hoped we could get away with using a switch to help drive the lines. > Is it Cat 5 or 5e? Stranded or solid core? What's the margin of error Probably Cat 5e, but I didn't specify it. It is solid core; we connected it using insulation displacement connectors at each end. > on the 70 m? :-) What else is lying alongside it to interfere? How > long has it been there? We bought a 100 m roll of cable and cut off around 30 m at the end. There is probably another 3-4 m of drop cables at the antenna end and 0.5 m at the Pi end. There is nothing to interfere as far as we know. The first 30 m or so is buried alongside a plastic water pipe; the rest runs along a hedge line and is attached to a barbed wire fence. > https://en.wikipedia.org/wiki/Cat_5#Maximum_cable_segment_length says > 100 m, and implies that's 90 m of solid core with patch cables at the > ends, but don't just read that bit of the page. :-) We didn't. > There's test equipment like Fluke's that I've seen mentioned a lot, but > mainly alongside them being good but expensive. :-) > http://www.flukenetworks.com/enterprise-network/network-testing/CableIQ-Qual > ification-Tester We have a fairly cheap Ethernet tester, which shows that all terminations are good on both the slow and fast speed settings. I'm think more about the specifications of the driver/receivers in the two devices. That spec that you referenced says that the maximum operating voltage is 125 V, but we're not going to get that from a Raspberry PI! I haven't managed to find anything on that aspect of the spec, but as I understand it, each driver/receiver pair is current driven, so the driver increases the voltage until the current required is achieved. I would expect cheap switches (especially ones that run off low voltage DC (5 V for the TP- Link and 12 V for the Belkin) would struggle to get the current after 40 -50 metres or so. I was wondering how much people knew about commercial switches and whether they specify a maximum cable length? Finally, can Ethernet boosters be obtained, or can we only get away with a repeater half-way down the cable run? BTW. The fall-back is to move the server to the same location as the Antenna (this is a TP-Link TL-WA7210N Customer Premises Equipment). We will have to mount the server into an IP65 case, but we do have main available. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
