[MLB-WIRELESS] Mast-mounted radio, or LMR400?

[Shaun Lee Clarke]

I am currently setting up my old iBurst wireless Internet connection for a
friend.

 

I am using an external 14dBi panel antenna and a desktop modem (iBurst works
on the 1.9GHz frequency).

 

After playing with antenna placement on ground level, I realised that I
would need to have the antenna located higher to get a decent signal. So I
mounted the antenna to the existing TV antenna mast. This part went fine,
and the speeds went from an unstable 14kb/sec to a stable 80-100kb/sec. But
the issue is that I now either need to mount the iBurst modem on the mast
near the antenna, or I will need to use some LMR400 to extend the RF cable
and leave the modem indoors. I currently have a short pigtail to FME, and a
4 meter FME cable to n-male using some thin looking coax (no idea on what
it's called).

 

I think the cable run from the antenna, to indoors will have to be about 10
meters, maybe a little less.

 

What do you think? My concern with mast mounting the iBurst modem is that
weatherproof boxes aren't cheap, and not to mention the issues of
condensation, heat, ventilation etc. Although I already tried extending the
DC power with some decent quality cable, and that part isn't an issue at
all.

 

And my concern with extending the coax is obviously signal lost (and this
cable isn't cheap either). At 10 meters, I have calculated that a 10 meter
run of LMR-400 at 1.9GHz would give me about 1.9dB of loss. Although I
imagine I'm already getting a fair bit of loss with my 4 meter RF cable and
pigtail setup.

 

I used this site: http://www.timesmicrowave.com/cgi-bin/calculate.pl for
calculating the loss.

 

Any advice anyone can offer me would be great.

vsseclogo

Shaun Lee Clarke

Mobile: 0433 559 020

 

Victorian Space Science Education Centre (At Strathmore Secondary College)

IT/AV Technician

Email: shaun.clarke at vssec.vic.edu.au

Web: http://www.vssec.vic.edu.au <http://www.vssec.vic.edu.au/> 

Phone: (03) 9379-3456

Fax: (03) 9374-3855

Address: at Strathmore Secondary College, 400 Pascoe Vale Road, Strathmore,
VIC, 3041, Australia

 

Strathmore Secondary College

IT Technician

Email: clarke.shaun.l at edumail.vic.gov.au

Web: http://www.strathmore.vic.edu.au <http://www.strathmore.vic.edu.au/> 

Phone: (03) 9379-7999

Fax: (03) 9379-2812

Address: 400 Pascoe Vale Road, Strathmore, VIC, 3041, Australia

 

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