Hi Steve,
In my system design of SONET OC-48 and OC-192 telco backbone rings last
year, we used the figure of -0.08 dB for each fusion splice of single mode
fibers at a frequency of 1550 nanometers (nm). We also figured around -0.1
dB for the other clean, polished, and mechanically sound "non-fusion" type
connections used within buildings, etc. These were conservative figures,
too. After several 5.5 KM reels, the splices added up...slowly. Now, I
just can't believe that the connectors at the freq's we deal with (HF RF
instead of light) could even come near the attenuation of connectors at
light. This is a supposition on my part, but the data mentioned in the
relayed "senior project" post seem to point this out.
I believe Mr. Tom also pointed this out...
As I believe you said, and the "senior project" made mention of, let's make
sure our RF connections are clean, mechanically sound, and
weatherproofed! BTW, water and contaminant ingress in fiber splice cases
(just like rf connectors and cables), causes large losses. In many
regards, RF and light transmission lines are alike.
Here's that measured connector loss link again:
http://lists.contesting.com/_cq-contest/199609/0345.html
Also, I look forward to meeting you at a future WWDXA meeting. I'm in the
Bothell area now, and would sure like to make a mtg soon.
Interesting topic!
73 de Steve, KZ9G
At 12:09 PM 1/21/2002 -0500, you wrote:
>In a message dated 1/21/02 5:19:31 AM Pacific Standard Time, w8ji@akorn.net
>writes:
>
> > Loss is the least of our worries with connectors, by far the real
> > concerns are over-heating, voltage rating, and (if on VHF or higher)
> > SWR.
>
> To that list I would add "weatherproofing" - more connector problems are
>attributable to poor weatherproofing than any other failure mode.
>
> The 0.2 dB is a figure I cited that the Andrew Company uses in their
>cable loss calculator program.
>
>Cheers,
>Steve K7LXC
>Tower Tech
>
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________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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