433MHz to LAN gateway or miniserver?

About 300 meters or 1000ft. However, that includes RF-unfriendly turf.

$400 for an industrial bridge won't fly. But yours are for large data rates which we really don't need. It would be like using a 40-ton truck to buy the groceries ;-)

WRT to inter-symbol time the DECT standard must be quite screwed up. Multipath notch-out happens exactly at the office desk I am normally using. Hurumph! I want my old Cincinnatti Microwave phone back, they knew how to do this stuff right without some standards committee sipping Perrier ... but AFAIK they dropped all this and concentrated on radar detectors.

...even if those transmit settings are intended to be mucked with as part of normal operation.

Been there. It keeps the lawyers employed.

It's not just RF products. Anything to do with RF compliance or even safety certifications can fall into this category.

That's about our useful limit in normal circumstances. With a lower datarate this shouldn't be a big deal.

In our case it's the ceiling of the Super Dome that drives us nuts. ;-)

On a sunny day (Sat, 03 Apr 2010 09:20:56 -0700) it happened Joerg wrote in :

Look dude, your stripes ... WDIC! I have been through that approval stuff before The WAP has a hidden serial port, I connect to it. F*ck your objections to anything, I am merely pointing out how it can be done, how I did it, so that it already exists, and if you do not like it find your own solutions. This is about design, not about your frustration with some agency, And I am not in USofApe either.

Normal circumstances in this case could mean a tropical storm barreling through while still needing to transmit.

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That I can surely believe, it's a massive structure. You'll probably have to prop up an arsenal of directional antennas.

Right now we are using 418MHz quite successfully. But of course for international markets it would be better to move to 433MHz, pretty much the only option other than the GHz bands. Antennas aren't a challenge in our case, it's the short rubber duckies.

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Other domes aren't such a problem (though the new Dallas domed stadium is another). Directional antennas don't help on the base (even on the ceiling pointed down) and don't work very well attached to a human walking about. ;-)

That's what we're using for the base. The mobile unit has a patch built into it (no protrusions). That's a problem below 2.4G.

Well, my clients care and so I have to :-)

Then you should know that what you write below can void a cert. It is very easy to say "Oh, it's all a piece of cake". You have a good knowledge of electronics and you can do it. So could I. Except that my stuff is not hobby, therefore ...

In Europe the rules and regs are even more onerous. BTDT, lived there, worked there, did radio certs there. Has nothing to do with frustration and I don't have any. However, such agencies make the laws and are the law.

Let's keep the tone a bit more professional, shall we?

Nice project! I have a Linkstation (a NAS) and installed a custom firmware and a regular Debian system some time ago (Apache works without problems). Looks like a serial port can be added to this device, too:

A NAS with 500 GB hardddisk for 100 euro and the capability to add custom hardware with a simple serial port protocol and control it from a Linux system, sounds like some interesting ideas can be implemented with it without much work. A long-term recording seismometer with high sample rate would be cool :-)

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Why don't they help at the base if you'd use helixes and the like? The person can't have one of course and you'd need stage hands to follow persons with the base antenna. And not smoke any "stuff" while doing that job :-)

I assume a motion to get the dome painted with RF absorbant coating on the inside would get dismissed ...

There are ways to use heavily shortened non-protruding antennas down there, or use any otherwise attached cables as antenna. But not knowing the app it's hard to say.

The firewall-router here in the office is a SMC Barricade. It has both a serial port and a parallel port built in. The RS232 is meant to be used as backup if the connection goes down and the other is for a printer. I could imagine one could hack that (but I don't know, other than that people have talked to the router via RS232) and then you wouldn't even have to fire up the solder station :-)

On a sunny day (Sat, 03 Apr 2010 13:13:46 -0700) it happened Joerg wrote in :

Yes, sorry typo: USofApes

You are one of the people from whom I would not have expected rude remarks like that. Sad.

I would. He's been a US hating Europeon for the decade or so I've known him on the Usenet.

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Well, the "stage hands" are the users so the unions would be happy to have a stage hand per stage hand (per...) for full employment.

I'd think it would have to be pretty good stuff, if it were reasonable financially. The distance off the roof isn't very different than a straight line. 1/r^2 isn't going to help much so the material would have to do everything.

Shortened antennas aren't as efficient, which is a big problem. We're fine with the 2.4G antenna but it's a close call whether we'll find a suitable antenna at 900MHz. 433 would be twice again the problem. As you alluded to before, though, 900MHz is really only suitable for the US.

I know someone who turned the Linksys NSL2U into a remote doorbell logging device for 100+ shops from a big franchise. Now they can see exactly how many and when people went into their stores. Modifying the NSL2U was the cheapest way to get the project done.

The Slug is a great little gizmo. I have two running the Unslung distro, keeping 1.5 TB NAS online as well as running a bunch of other utilities.

Cheers

Phil Hobbs

On a sunny day (Sat, 3 Apr 2010 22:18:23 +0200) it happened Frank Buss wrote in :

You can hang my scope_pic from th RS232 and remotely scope anything: *** **** *** *** *** *** * * * * * * * * * *

• * * * * * ** * * * * * *
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• * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** * *** * * * ** * * ***** ***

• * * * * ** *

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-- **** * * * * * * * * * * * *** * ** ***** *** * ***** ** *** **** * * ** * * * * * * * * * * * * * * * ***** * * * ***** * * * * * * * * * * * * ** * * * ** **** * ** * ****

• * *
• * * * * * * * * * **** *** * ** ***** *** * *****

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• * ** * * * * * * * * * * * * ** * ** * * * ** **** * **
• **** ** **** *** * * * *

One of our designs is a switch plus a small microcontroller with network connectivity and some I/O (including a serial port). If I'm counting right that device has turned into 15 different products already!