[MLB-WIRELESS] Cheap(?) 15mtr Telescopic masts
vak at alphalink.com.au
Thu Dec 2 12:16:55 EST 2004
I've currently use revision 4 of my "dlink in a waterproof box" up on
the mast - no amp currently in use.
It's been up almost 3 yrs now (although revision 1 and 2 were not so
good - in once instance water got in and killed the AP).... If you are
going to put anything outside, I recommend it goes straight into a
diecast aluminium box with UV stable (polymer) silicone. Wherever a
penetration occurs in the box (even underneath), make sure it's
The last 8 months or so, the AP has shown occasional erratic behaviour
and requires a reboot once or twice a month - the handy bit about a
remotely powered AP is that it's fairly easy to reset - turn the thing
off at the power point! I suspect this behaviour is due to the extreme
temperatures the AP has been subjected to. A 30 degree day with a bit of
sun can quite easily bring the internal ambient temperature up to 70
degrees. A possible solution to this would be a box inside a box - The
internal enclosure would encase the equipment, be externally lined with
fiberglass insulation and finally enclosed in a bottom vented box.
If you're going to be fooling around with firmware upgrades (or anything
outside normal "home" use), I'd recommend wiring up the reset button so
you can remotely engage it.
I believe you can expect 2 to 3 yrs of life out of a $100-$200 AP. All
the AP's in this price bracket are much the same and have their own
Also, if you have the luxury and time to choose, find a low heat
dissipating AP (or tune the input power if it doesn't have an internal
switchmode supply). - helps in keeping temperatures down.
On a side note, if your mast & install has to "look" good, I suggest
using stainless steel guy wires - they are generally thinner (for the
same tensile strength in galvanised), but are however more expensive.
Dan Flett wrote:
>>This'd only happen if you weren't happy with 12mtrs..
>>Surely 12mtrs is enough for everyone :-)
>Yeah well, due to over-enthusiasm, the first mast burned down, fell over
>and sank into the swamp. But the second mast stayed up! (at 12 Metres).
>A word of advice to everyone using these masts - each 3 metre segment
>you add makes it exponentially more difficult to put up. 12 metres is
>very difficult with 5 people to put up. With the gear I was trying to
>put on top of it, 15 metres was a disaster waiting to happen. The thing
>that fooled me into a false sense of security was that two people can
>actually put these things up to 15 metres with no guys on a calm day,
>and it looks like it'll be easy to put antennas on. Wrong! Once you
>put gear on them, they wanna bend over every chance they get - the more
>gear the worse it is.
>They need to be fully supported through the whole lift. I used 3 ropes
>attached to the top and fed them through fixed eye-holes on the ground -
>the eye-holes give the person holding the rope a mechanical advantage
>against the vertical mast. The 3 rope-holders then just feed out the
>rope as the mast goes up.
>Make no mistake - you can't put these masts up with a half-assed effort.
>You need to be organised and mechanically capable.
>If you're going to use less than the whole 15 meters, discard the
>thinnest sections first - the lower sections are thicker and have more
>A 12 metre mast requires a building permit in many areas. However, you
>might get away without one if you just ask all your adjoining neighbours
>nicely. I knocked all their doors - including those adjoining the back
>fence - and showed them the picture from the Telomast instruction
>leaflet. None of them had a problem with it.
>Finally, if you've built yourself a you-beaut home-brew PoE AP-in-a-Box,
>don't put it up a mast that's going to require 5 or more people to put
>up and bring down. Consumer-quality APs have a tendency to hang,
>especially in extreme temperatures, and you can't do much about it if
>it's stuck up a 12 metre mast. You'll be hosting lots of
>mast-lowering-then-raising barbeques if you do. I recommend placing
>active circuity within arms reach, although I believe Peter and Vaskos
>run amps on their masts. Amps are probably more reliable than APs
>To unsubscribe: send mail to majordomo at wireless.org.au
>with "unsubscribe melbwireless" in the body of the message
To unsubscribe: send mail to majordomo at wireless.org.au
with "unsubscribe melbwireless" in the body of the message
More information about the Melbwireless