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Old 28-12-2006, 09:55   #157
Elrond24
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Join Date: Dec 2006
Location: NW Surrey
Posts: 5
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Re: A little inside information by an Employee.

Quote:
Originally Posted by Escapee View Post
I guess they could, but I think it would be limited bandwidth.

I'm not sure how their automatic signal system works, perhaps someone may know if its done via RF telemetry or some other method?


PS: I wonder how they managed with comms when a train was on the line, ie: shorting the two lines together via the axle. I guess it could work because the frequency used wouldn't see it as a short unlike 50Hz or DC.
Hi thought I'd butt'in I am not an S&T Engineer but can say the railway is bad environment any comms no matter how sophisticated.

My experience lies in Power Transmission, but the basis of signal telecommunication is that on Overhead Power Tranmission DC signaling is used and on DC Transmission AC signaling.

Bad - in that our rectifier,s induce 300 hz into all adjacent copper cable's, our HT cable surges (be it for our network or the REC), induce upward of 1,500v, mother nature via Lightning strikes at or close to running rails destroy most front ends, TOC induce further interference via chopper ccts in their trains, every night especialy in the London area track ccts(running rails) are disturbed due to engineering. I will not go on !!

The greatest disapointment that Network Rail cannot extend their existing Fibre optic system nationwide for commerial use.
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