awr@sfmag.UUCP (A.W.Rofrano) (04/11/85)
I am looking for some sort of noise generator that will affect data transmitted over an Ethernet 50 ohm coax cable. I've called most of the instrument vendors with no success. ANY assistance will be appreciated. You may contact me at "attunix!asb". Tony Bartolomeo
mac@tesla.UUCP (Michael Mc Namara) (04/19/85)
In article <548@sfmag.UUCP> you write: > >I am looking for some sort of noise generator that will affect data transmitted >over an Ethernet 50 ohm coax cable. I've called most of the instrument vendors >with no success. ANY assistance will be appreciated. > >You may contact me at "attunix!asb". >Tony Bartolomeo I can remember talking with a friend who is now working for AMD in Austin Texas about a Ethernet -- noise problem. He was System Manager at U of Texas, and just about to leave to take a job with Motorolla, when suddenly the system got all kinds of errors on the Ethernet link. He tried everything, any kind of problem he could think of. The University was getting kind of pissed, 'cause he was soon leaving, and the problem wasn't fixed. He pulled various cards in the backplane. (Seems they had a lot of their own local additions to the computer.) No help. He tried running an older version of the kernal. No difference. He re-did the connections. Nothing he tried helped. To shorten up the story, the problem wasn't in the computer, or the computer room; the cable ran over a flouresent light in the ceiling of the hall outside; you know, the light that was flashing dimly? Well, each flash the light made involved the ballast generating a huge magnetic field... ------------------------------------- On a clear disk you can see forever ] Michael Mc Namara @ cornell ------------------------------------- mac@tesla
sm@cadre.UUCP (04/25/85)
In article <548@tesla.UUCP> mac@tesla.UUCP (Michael Mc Namara) writes: > To shorten up the story, the problem wasn't in the computer, or the >computer room; the cable ran over a flouresent light in the ceiling of the hall >outside; you know, the light that was flashing dimly? Well, each flash >the light made involved the ballast generating a huge magnetic field... Although this isn't a response to the original question, the magnetic field that you mentioned (resulting from failing ballast in a flourescent light), can also play havoc with magnetic mice. This "guess" saved us a $99 field service call. Sean McLinden Decision Systems Laboratory