> You could probably use the RJ45 (modular UTP) connector to get separate
> RX/TX signals as well. A third (and more expensive) option is to get a coax
> to fibre converter for the signal.
Did contemplate the direct use of the 10baseT signal but a few things disuaded me:
1) The signal is differential,
2) the signal is filthy, all sorts of rubbish on it,
3) Line receivers/drivers for the 10baseT (RJ45) to AUI interface are becoming
increasingly difficult to get. Most now deliver clock & data.
> The ID requirements could possibly be met by having a dedicated node on the
> wired network side that sends a broadcast (in the ethernet sense) ID
> somewhat more often than required (this will allow for delays due to
> collisions). I'm not sure of the UK requirements, but in the US sending it
> in plain ASCII every 8-9 minutes would generally ensure compliance.
My reading of the UK Licence conditions is that a digital station must id
once every 15 mins in morse at no more than 20 wpm. That is not going to do
the bit error rate much good! This issue will need to be resolved country by
country.
> If you want to use such a system on a network with multiple computers (that
> is 2+ computers connected via wire) the radio<-->ethernet should probably be
> on the other side of a packet forwarding firewall for several reasons.
> 1. The firewall will prevent network traffic intended for the wired network
> from being transmitted over the air.
> 2. The firewall could be used to prevent other hams (or worse non-hams) from
> gaining access to inside systems.
> The firewall machine could also be the one that sends the ID packets, with a
> UN*X firewall the command could be run by cron.
Sorry, I have assumed that any 10Mbit link will have come through a firewll
router to restrict the traffic and access. Also I am assuming only 2 stations
involved. My deliberations are only for the point-to-point trunk links. For
local area multi-drop access I would look at 802.11.
> I am also very interested in the idea and have been thinking about it (as
> opposed to actually studying it) off and on for the last two years.
> Unfortuneatly I seem to have the same limitations--young family, limited
> financial resources... :(
--
Regards
Richard
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Amateur radio callsign: G1SOG Home BBS: G1SOG@GB7SDN.#49.GBR.EU
Amprnet co-ordinator for Wiltshire
My opinions are mine, all mine. None to spare for unopinionated masses.
This message comes from a WinTel free zone. CPU = Cyrix, OS = Linux.
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