[time-nuts] sub cables

[Bruce Griffiths]

Magnus Danielson wrote:
> From: Scott Mace <smace at intt.net>
> Subject: Re: [time-nuts] sub cables
> Date: Thu, 01 May 2008 16:30:43 -0500
> Message-ID: <481A3683.4050300 at intt.net>
>
>   
>> A repeater or regen goes optical-electrical-optical.  I think you are
>> talking about an EDFA.  While it may pass light when it's down, one
>> has to take into account the optical budget of the span.
>>     
>
> Modern sub cables does not used a distributed line of EDFAs anymore. They use
> the entire cable length as an amplifier instead. If the laser is down, you can
> reach it and service it, since it sits on dry land anyways.
>
> I have an EDFA lying around my office desk. Never know when I need one.
> Uses a 250 mW 850 nm pumping laser.
>
> Cheers,
> Magnus
>
>   
Magnus

There is a limit to the cable length when using EDFAs above which a 
regenerator is required.

Bruce