433MHz to LAN gateway or miniserver?

This time it doesn't have to be super low cost. But at the same time it shouldn't be over-engineered. This easily happens when standards committees get together. What's the old saying? Too many cooks spoil the broth.

Well, if there were off-the-shelf units at reasonable cost I wouldn't care whether there is a 32bit ARM in there of some lowly 8051.

Yes. Even mounting the antenna yourself can already put you into a legal gray zone. Doing the box and antenna mount yourself definitely will.

For hobby projects all this may sound easy but when it's a consumer product that's a whole different ballgame. Sometimes younger engineers tell me "Oh man, it's so easy, you simply do this, that and the other thing and you're done". Until they have to trudge through the paperwork of EMC cert themselves for the first time and a check for a princely sum is plopped onto the table at the compliance lab. After that they usually never say this again :-)

Hmm... so I might guess that something like this:

---Joel

Not necessarily. If you use a pre-certed module with its native antenna and just place that pre-certed stuff inside a plastic shroud you can be ok.

Maybe they are just a re-packager when it comes to hardware.

On a sunny day (Fri, 2 Apr 2010 19:11:35 +0200) it happened Frank Buss wrote in :

I was thinking one of these:

If that link does not work, go to

This is the tranmitter in the box: ftp://panteltje.com/pub/lremote_transmitter_img_1004.jpg the box is also from conrad, adn also very cheap, and small.

I bought a bunch of these boxes for small pic projects like this: ftp://panteltje.com/pub/LED_control_box_img_1162.jpg That black thing on the side is a connector shell with a LDR photocell in it..

On a sunny day (Fri, 2 Apr 2010 10:49:50 -0700) it happened "Joel Koltner" wrote in :

Joergman is paranoia

Nope, but I've got over 20 years of agency approval processes under the belt :-)

Note the Jennic modules are 32bit with lots of resources:

These are very nice modules.Retail for about $16 in volume. Unfortunately not available for 433MHz only 2.4GHz.

Mark.

Yeah, I looked at their site :-(

The other thing that I couldn't find is a LAN link. That's missing in many systems that are targeted at the home health market. Which I'll never understand because there are more and more people who don't have a phone line anymore but they do have broadband Internet access. One of them in this neighborhood is in her 90's.

I know this is what your looking for, but I have no idea about the price.

Cheers

Aha, thanks! They only offer a transceiver for 900MHz, not 433MHz so we'll have some problems internationally but it can't hurt to talk to the guys about it.

Pity that they don't do 433MHz. The beauty of the Jennic module is that the

If you could cope with high powered 2.4GHz that might get you the range you want but might also restrict the markets you could sell in, Jennic also do high powered versions of those modules.

Mark.

High-power 2.45GHz can cause serious market restrictions overseas. Also, ideally we don't want to piece it all together ourselves. The product line Martin pointed out seems to have the potential for a real plug-and-play situation:

Ok, no 433MHz transceiver but with our qties they might be willing to give us that. If their RS232 RF transceiver can talk to this little server they've got then we'd almost be home, because then we could simply plug our RS232 lines from the uC in there and be done.

I think it's mainly an installation problem (or at least the perception of one) -- the average customer can properly plug in a phone, but while in many instances you'll have, e.g., a router running a DHCP server so it really is "plug and play" for a home health widget, when it *doesn't* work troubleshooting is not something grandma can usually do successfully.

Plus companies like Life Alert ("Help, I've fallen and I can't get up!" -- you know those guys charge something like $40/mo for their system? Sheesh!) never exactly struck me as being all that technology-savvy anyway.

But heck, you've identified a real market need here -- given time, someone will surely step in to fill it.

True. However, I know a lot of people who have no land line since years. Including people who must go to the front porch in order to be able to see if someone left a message on the cell. But all of them have a cable modem.

Well, but for that money they have to have a minimum staffing level and they also call in regularly. "Hey, how'ya doing today?" I bet that alone has resulted in ambulance calls before it was too late.

I doubt it. Look at the home automation market. Most companies there are IMHO sound asleep.

On a sunny day (Fri, 02 Apr 2010 15:30:54 -0700) it happened Joerg wrote in :

A while ago I added some I/O to my Linksys WAP:

So I have it all, wireless, LAN RJ45, analog I/O, digital I/O, controlled from anywhere, webserver too on SDcard, the works. Couple of dollars only. Oh, and it has a buld in temp controller with night and day setpoints. remote monitoring of anything you want. Oh, and the WAP runs Linux. The whole thing is for sure < 100$ i none of quantities.

Ahead again.

If you've added no function to the box, perhaps. Add any function and you have to certify again, often on a country by country basis (particularly in Asia).

Or they're skirting the law. In the US they're unlikely to get into hot water unless someone turns them in (often a competitor).

For hobby, yes. For a commercial product that goes into the consumer market, very different thing. The millisecond you hack a device that contains a two-way radio function you are back to zero WRT agency approvals. T'is life :-)

If you don't believe me or think I am paranoid or whatever then ask a guy at an accredited lab or a senior underwriter at a product liability carrier. And yes, compliance is required pretty much worldwide.

How much range do you need? We're quite happy at 2.4G, except where there is massive multi-path that just happens to be just far enough away to match our inter-symbol time. For those few places, 900MHz looks like the answer if we can get the antenna right. Our module is expensive and our bandwidth requirements are much more than yours so maybe there is something cheaper that would work.