RE: pigtail questions

Assuming your numbers are right (I personally think the connector loss
number is probably too high *for a properly installed and maintained
connector*, but the argument works better if I just use your numbers)

    12" of LMR-100 + 48" of LMR-400 plus the connector pair to hook them
together: 
       .19 + (4 * .068) + .5 = .962

    60" of LMR-100:
       (.19 * 5) = .95

The difference in loss is negligible, and in the favor of the single 60"
piece of LMR-100. The single piece of LMR-100 will be cheaper than a 12"
piece of LMR-100 *and* a 48" piece of LMR-400 *and* the connectors necessary
to hook them together (remember you need one male and one female (less
commmon) N connector to do it without the extra loss of a double-female
adapter), plus you'd need to keep that connection weathertight.

I stand by my original claim that at 60", the single chunk of LMR-100 is the
right choice, but at 60', something bigger (at least LMR-600 at these
frequencies) is the right choice.

Matthew

> -----Original Message-----
> From: [email protected] 
> [mailto:[email protected]] On 
> Behalf Of Jeff Liebermann
>
> No.  LMR-100 is good coax for short pigtails, but not long 
> runs.  LMR-100 is about 19dB/100ft or 0.19dB/ft.  3dB is half 
> your power so 15.7ft of LMR-100 will eat half your power. 
> Actually it's a bit worse than that as each connector pair 
> will eat an additional 0.5dB.
> 
> The whole idea behind a pigail is to provide a flexible 
> connection to your LAN card so that the big, fat, heavy, and 
> low loss coax cable to the antenna, doesn't break off the 
> connector on the wireless LAN card.
> 
> > I see all of these 12"
> > pigtails offered -- does that mean these people have the antenna 
> > within 12" of the radio adapter?  I think I'm planning to get a 60" 
> > pigtail, since that seems to be a convenient length.
> 
> No.  Antenna runs should be made with LMR-400 or LMR-600. 
> LMR-400 is 6.8dB/100ft or 0.068dB/ft.  Much less attenuation 
> than LMR-100.  
>  
> 

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