Hi guys,
Would it be better to use a scope or spectrum analyzer for RS-485 analysis? I may have some noise problem but need to investigate. I'm getting a combination of additional unexpected data on the bus, alignment issues and CRC errors. Some times an extra character appears in front of the data packet.
If it would be the spectrum and the spectrum expects 50 ohms load what would I need to add externally to measure with the spectrum.
Load on the ends of each RS-485 side should be about 120 ohms so this in parallel I expect would be half. However, currently the line lead on the RS-485 bus is less than a meter long so it isn't terminated at either end.
Cheers,
John