Here is what I did:
I stripped the insulaton of the TX+ and TX- wires in the CAT5 cable
near one end of the cable (the one near the CPU). The other end went
into a 10Mbps Hub.
I used a 200MHz isolated channel oscilloscope to take the measurement
of the differential signal on the TX+ and TX- wires. The Probes were
set to 10X attenuation to keep the bandwidth up till 200 MHz
I tried the same measurement using different setups.
The resultant waveforms are available at:
I have also referred to:
ANSI-IEEE Std 1802.3d-1993 (Conformance Test Methodology for IEEE
Standards for Local and Metropolitan Area Networks)
- Type 10BASE-T Medium Attachment Unit (MAU) Conformance Test
Methodology (Section 6)
According to the waveform given at the start (page 10) of this
document, it seems that what I captured is quite what is required but
still I would like the comments and opinions of others.
I wasnt able to find much regarding waveforms of the ethernet signals
thru gools so I would be happy if you would go through my findings and
post in your comments.
Regards and best wishes for the new year
Larsen and Toubro EmSyS, Mumbai India