| ??? 02/20/09 13:02 Read: times |
#162593 - CAT5 ethernet cable Responding to: ???'s previous message |
Ap Charles said:
That means you get reflections with 120 Ohm Resistance .Which indicates the characteristic Impedance of your transmission line is NOT EQUAL to 120 Ohm. A slight impedance mismatch may not be a problem. There is no hard n fast rule to always select a 120 Ohm resistance to get things going.Actually If you have very long cable and are experiencing noise problem withot the[EDIT] proper [/EDIT] Termination resistances you can use one (within reason)and when required .
Regards/ Ap Actually I'm using CAT5 ethernet cable do you have any idea of its characteristic impedance? Mahmood |
| Topic | Author | Date |
| RS485 problem | 01/01/70 00:00 | |
| Just 1? | 01/01/70 00:00 | |
| The 120 ohm resistor | 01/01/70 00:00 | |
| VCC = 5V | 01/01/70 00:00 | |
| you need | 01/01/70 00:00 | |
| Scope? | 01/01/70 00:00 | |
| daisy chain | 01/01/70 00:00 | |
| Some hints... | 01/01/70 00:00 | |
| 100 meters | 01/01/70 00:00 | |
| 7 clocks | 01/01/70 00:00 | |
| Topology | 01/01/70 00:00 | |
| RE: topology | 01/01/70 00:00 | |
| don't | 01/01/70 00:00 | |
| Yes, don't! | 01/01/70 00:00 | |
| Getting there | 01/01/70 00:00 | |
| So, what was the cause of failure? | 01/01/70 00:00 | |
| not yet | 01/01/70 00:00 | |
| with additional components | 01/01/70 00:00 | |
| Where do you have this circuit from? | 01/01/70 00:00 | |
| from my Mentor | 01/01/70 00:00 | |
| Ben's site | 01/01/70 00:00 | |
| Mission Accomplished | 01/01/70 00:00 | |
| I'm not sure I agree | 01/01/70 00:00 | |
| exactly | 01/01/70 00:00 | |
| Maybe I misunderstood your earlier post | 01/01/70 00:00 | |
no | 01/01/70 00:00 | |
| yes | 01/01/70 00:00 | |
| then how could you ask .. | 01/01/70 00:00 | |
| With noise+etc reduction | 01/01/70 00:00 | |
| email updated | 01/01/70 00:00 | |
| here's info's........ | 01/01/70 00:00 | |
| That means you get | 01/01/70 00:00 | |
| Only when seeing nosie? | 01/01/70 00:00 | |
| Not exactly but as per requirement | 01/01/70 00:00 | |
| CAT5 ethernet cable | 01/01/70 00:00 | |
| 100 Ohm | 01/01/70 00:00 | |
| More details here | 01/01/70 00:00 | |
| did you check the FAQ? | 01/01/70 00:00 |