saw filters

Jun 19, 2016 23 Replies

That is not the case in the POCSAG protocol. But maybe the pagers had a duplicate-message-within-short-interval rejection in the firmware. I never actually tested that... Still have some old pagers here but lost interest in this technology.

When you say "mesh" I think of the MESH company and that means Ethernet/802.11. That's different waveform than pagers.

It's possible to have two waveforms in one box but it's not the usual thing to do.

Les Cargill

Les,

I used the term "mesh" as a network topology (in contrast to a star topology or hub-and-spoke).

I agree, ham-radio mesh-radio is usually equated to HSMM (i.e. wifi IBSS/adhoc mode) but you can implement the topology on top of every RF layer.

Mesh-networks can be routed (e.g. using oslrd) or flooded. So, in fact, APRS is an example of a flooded mesh network.

The excelent radiohead arduino-library is another example. It supports different kinds of radio-module (covering 2 m, 70 cm and 13 cm ham-band) ... and includes a mesh mode:

formatting link

And this is where all these ISM-band devices come into play, for two reasons:

- they are "mass-market" so they very cheap

- quite a few of them can be modified to offer modes not legal for ISM-band use, but very much legal if you have a ham-licence. (like wifi on 2.3 Ghz or between 5.65-5.85 Ghz ... or these 2 Watt 433 Mhz modules, ... ).

For me the most fundamental issue here is that this technology offers the possibility to build sollutions, not on "high power / few radio" but "lots of radio @ low power": networks of intelligent nodes.

And I think this is an area where ham-radio still has a lot to learn.

Cheerio! Kr. Bonne.

Yeah, I suspected.

some would be more equal than others :)

*Kewl*

Yeah; I am actually habituated away from those sorts of solutions.

Les Cargill

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required