The biggest problems you are likely to encounter are not from signal
strength/attenuation issues but from ground loop and lightning
protection issues. The best solution would be to use a fiber
converter. The next best solution would be to use the cable but to
make sure to install lighning protection on each end with the proper
ground connections made. You can buy DS3 repeaters but they require
you to use a power inserter to add voltage to the line to power the
repeater. That might buy you some signal strength since the total run
will probably be longer than the 450 feet across the parking lot. I
think ADC makes some of those. You can ask someone at Walker and
Associates for a DS3 repeater and they might be able to help.
Dont forget that you need to use cable that is rated for an outdoor
installation. Innerduct or no innerduct, there WILL be water ingress
and that can ruin a cable very quickly. Especially when there is
voltage on the line.
-Richard
Ejay Hire wrote:
I've had at around ~450 feet, but you have to change the LBO/Cable
length in the CSU.
-----Original Message-----
From: Robert E. Seastrom [mailto:rs@seastrom.com]
Sent: Thursday, April 17, 2003 10:51 AM
To: Mike (meuon) Harrison
Cc: nanog@merit.edu
Subject: Re: DS3 Coax..
"Mike (meuon) Harrison" <meuon@highertech.net> writes:
> I need to run a DS3 across our parking lot.. Seriously.
>
> What's the max length I can use coax for (I know, gotta use a
GID),
> and what's the best brand/type of coax I can use? It'll be through
> innerduct.. Looking for some real world answers from people that
do
> a LOT more of this than me.. (It might take 350-400 feet).
The textbook limit is 450' for 735 cable. I've had poor luck pushing
the limit, and don't know offhand if using some other flavor of 75 ohm
cable buys you anything.
Were I in your position, I'd have glass pulled and use a coax to fiber
media converter such as http://www6.adc.com/ecom/hier?NODE=OND68947,
http://www.versitron.com/DS3T3.html,
or
http://www.rad-direct.com/DATASHEET/FOM-T3.pdf
(the latter of which
I've used personally) on each end. No, it's not the cheap way to do
it, but it eliminates ground loops and other such nastiness that can
ruin your whole day.
---Rob