>| Actually, you're dead right. The outside antenna has a considerably
>| more than adequate amount of cable and it's relatively small in
>| diameter which guarantees substantial loss.
>RG213 isn't all that small as coax goes, but see my previous posting for
>detailed loss numbers. The basic question of why one would want to sell
>an antenna kit that can't possibly help remains. Another question for all
>these FCC-mandated pre-connectorized antenna cable assemblies is: how are
>you supposed to comply with NEC grounding requirements?
I have the first model and the cable is something considerably smaller
than RG-213. I can't tell you the designation as it's not printed on
it, but it's about the diameter of 59/u - smaller than 6 but larger
than 58. I suspect the reason for selling it is that while their ERP
is limited by the FCC (as you mention later), the outside antenna does
allow for a better omnidirectional pattern.
>| I understand this is as
>| directed in their license.
>Interesting. Pointer? (They do have a 30ft version now.)
Don't have one - that's just repetition of a remark I read in an
amateur radio group.
>| You will note that they use a connector
>| which you cannot buy: I think an "S" type with a reverse thread.
>| What you might do is to splice the cable, removing all the excess and
>| using a type "N" or similar low loss connector. You will need to keep
>| the original connectors so that you can connect to the base.
>Which connector are you talking about? The connector on the antenna (and
>on the antenna end of the cable) is a standard N. At least it was in my
>kit. The connector on the base end is a reverse-thread TNC. These are not
>yet as available as reverse-polarity TNCs, but I've seen them listed online
>at at least one location. In any case, there is no need to splice. You can
>simply cut off the antenna end and put a new N connector on the shorter cable.
On my kit, it is not an N connector. It is a reverse thread "S" - at
least I believe it is. I don't use them. It is about 1/4" in
diameter and threaded like a PL-259 - sort of a miniature version of
one, but I think I've seen it elsewhere used at UHF and beyond.
Actually, are you talking about the connector at the antenna end or
the phone? I don't recall what they're using at the antenna, but the
connector at the base end is as I describe it above.
Quote:>As an interesting aside, when I first got the kit I used the coiled-up cable
>as an adapter only (RT-TNC->N) to connect to an N->UHF adapter to connect to
>about 100ft or RG8 to a discone on a 40ft tower. With this I got just about
>the same range as with the built-on antenna and later with the supplied
>EnGenius antenna on a 10ft mast.
I'm wondering what would happen if I shortened the wire and stuck an N
type male to female to connect it. Or better yet, used some
semi-flexible hardline to a short piece of the original. I suspect
your discone would have done better with a better feedline. RG8 is
pretty lossy at 900 mhz. Still, both the discone and the supplied
vertical have a pretty low angle of radiation, and the RG8 can't be as
lossy as the stuff they supply. I wonder why you didn't see an
>| I believe that they use both 2.4ghz and 900 mhz spread spectrum - both
>| of which are quite lossy in small cable.
>No, it's 900 only.
>| I'd actually expect over 3
>| db loss, but I'm just guessing.
>And you'd be right. :)
>|I also think that the FCC lets them
>| get away with a higher power level (I think around 900 mw or 0.9
>| watts) due to the fact that they use spread spectrum which, by it's
>| nature, causes lowered interference.
>The FCC lets part 15 DSS devices go to 1W, but it's 1W of effective isotropic
>radiated power, so the calculations can get tricky. The original EnGenius
>equipment was 600mW. The new version ups the base to 900mW but the handsets
>remain 600mW. Unless they made a comparable improvement in the base's receiver
>sensitivity, it isn't clear that the extra power can help. I see no difference
>in range between old and new.
> Dan Lanciani
Not all that tricky - just take the dbi gain of the antenna, reduce it
by the loss in cable and connectors and apply it to the transmitted
power. Thing is, as we both know, an extra 3db, while helpful, won't
make a staggering difference.