On 8/30/2011 1:26 PM, Rob wrote:
wrote:

"Geoffrey S. wrote in message
...


snip


Geoff.


If your intent is to experiment with the cheap duplexer, what I have to
offer is irrelevant. However, if you aim to build a repeater, consider
getting your isolation over distance (much greater than 10m). Put the
transmitter and receiver a few km apart and link them using another band
authorized in your area (440?).

I encountered this in Key West Florida some years ago. Worked fine there.

It is done here on 10m, where the duplex offset is only 100 kHz and
a duplexer is physically very large.

However, what I hear from the repeater team is that one is in fact
building and maintaining 2 repeaters, doubling the chance of any faults
and problems. Setting up the 10m repeater was much more work than
everyone envisioned, and many had experience on 70cm etc.


What about VoIP using 802.11 as the link. These days, that might be
easier than trying to cobble up a 440 remote link.

Jim Lux wrote:
On 8/30/2011 1:26 PM, Rob wrote:
wrote:

"Geoffrey S. wrote in message
...


snip


Geoff.


If your intent is to experiment with the cheap duplexer, what I have to
offer is irrelevant. However, if you aim to build a repeater, consider
getting your isolation over distance (much greater than 10m). Put the
transmitter and receiver a few km apart and link them using another band
authorized in your area (440?).

I encountered this in Key West Florida some years ago. Worked fine there.

It is done here on 10m, where the duplex offset is only 100 kHz and
a duplexer is physically very large.

However, what I hear from the repeater team is that one is in fact
building and maintaining 2 repeaters, doubling the chance of any faults
and problems. Setting up the 10m repeater was much more work than
everyone envisioned, and many had experience on 70cm etc.


What about VoIP using 802.11 as the link. These days, that might be
easier than trying to cobble up a 440 remote link.

At first they used (or planned using) an FM link on 23cm, then they
switched to digital voice over 802.11a (6cm), then to 802.11g on 13cm,
and I think they now use a wired internet connection.

On 8/30/2011 5:13 PM, Jim Lux wrote:

What about VoIP using 802.11 as the link. These days, that might be
easier than trying to cobble up a 440 remote link.

Joy!

I am going to sit back and see how this suggestion evolves.

tom
K0TAR

tom wrote:

I am going to sit back and see how this suggestion evolves.

Look at SVXLINK. It's an open source package that runs on Linux (and possibly
BSD) that does exactly that.

It includes support for remote receivers (with a voting option), remote
transmitters, and an echolink server.

We plan to use it with hard wired internet links, but who knows, an 802.11
link could work. Unlike the US we are restricted to 100mW EIRP, so no
gain antennas, etc, to make things work better.

Geoff.


--
Geoffrey S. Mendelson N3OWJ/4X1GM
Making your enemy reliant on software you support is the best revenge.

Geoffrey S. Mendelson wrote:
We plan to use it with hard wired internet links, but who knows, an 802.11
link could work. Unlike the US we are restricted to 100mW EIRP, so no
gain antennas, etc, to make things work better.

Do you have a transmit ban on 802.11 channels in 4X too?

We as hams in the Netherlands are no longer allowed to transmit above
2400 MHz except to an amateur satellite.

Rob wrote:

Do you have a transmit ban on 802.11 channels in 4X too?

We as hams in the Netherlands are no longer allowed to transmit above
2400 MHz except to an amateur satellite.

There is a limit of 100mW EIRP for 2400-2450 mHz for terrestrial use,
with a limit of 100W EIRP to satellites in the 2400-2402 mHz part of the
band. This is from a document on the Ministry of Communicatons website,
dated 1999. It has been unchanged except for the addition of 7.100-7.200 mHz
so they never bothered to update it.

The difference between a 100mW limit and an outright ban in practice is
very little IMHO.

For example, you can turn off encryption and use a WiFi device as a packet
radio, or you can call CQ on your cordless phone. :-(

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
Making your enemy reliant on software you support is the best revenge.