Didier Juges wrote: > Well, I am not sure I can tell much about how modern repeater power supplies > are made because I do not believe the spec I got is public domain, but I can > tell you it's a little more elaborate than a power resistor in series with a > shunt regulator, unfortunately. > > They are apparently running more than a few watts of electronics at each > repeater. Each repeater operates from about 200V input voltage nominal, so > 10,000 volts can drive about 50 repeaters in that case. I have not read the > spec in great details (we won't bid on it as it is commercial) but I will, > to try to figure out how they keep the voltages balanced. That's about 200W > of power for each node. > > Also, and this is absolutely not clear to me, but they want the full > isolation (10,000 volts) between input side and output side of the DC/DC > converters. If the repeater is composed of optical devices, even if they > convert optical to electrical and back to optical, I do not see the need to > electrically isolate the electronics from the power cable, as there should > be no other return for ground currents. > > 10,000 volts isolation with 2,000,000 hours MTBF in a 0.6" high package is > no piece of cake... > > Didier KO4BB > > Didier
EDFAs may be phased out in favour of using 1/2 as many Raman amplifiers which have a larger bandwidth. (EDFA bandwidth ~ 4THz, Raman bandwidth limited by the number of different wavelength counter propagating pump sources ) Bruce _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
