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May 2016
 

The Bellinghman
Date: 2007-01-30 11:19
Subject: *bulb*
Security: Public
I've just realised something. But let me explain.

We appear to have a black spot round our front door. I've managed to set off the car alarm twice now, just using the remote to open the doors. And half the time, the remote doesn't seem to want to work, while it does work perfectly well elsewhere. Also, we have a weather station, with a remote sensor just under the porch, and it seems to be attempting to transmit all the time, and the battery is draining fast, and its readings are totally laughable (from -20 to +20 C in a mere thirty seconds, while at a constant 20% humidity? I think not).

I just checked.

It appears that car remotes work on 433 MHz, just as the weather station does, and it looks like we've got a nice little punch-up going over who owns that frequency in that ten foot diameter area. I think we may have to find somewhere else to mount the sensor.
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Plastic Bertrand Russell
User: burkesworks
Date: 2007-01-30 11:43 (UTC)
Subject: (no subject)
Just a thought; you haven't any radio amateurs anywhere near you, given that 433 MHz is slap-bang in the middle of the 70cm band? At first I thought it may even have something to do with one of the repeaters, but I'm sure the one in Royston is for 2 metres, the nearest 70cms ones to you being in Ampthill, Welwyn and Huntingdon and thus well out of range!

Good to meet you at the weekend btw!
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The Bellinghman
User: bellinghman
Date: 2007-01-30 12:23 (UTC)
Subject: (no subject)
I'm fairly sure the problem is very localised indeed, and has only started since the arrival of the weather station (which proudly proclaims the 433 MHz on the pack). I assume that it's being licensed for very short distance control purposes, and that outside that range, it will have no effect on the ham radio band, nor vice versa. (How much power can a 2032 battery put out? Not much - it'll be quite strong very close by, but the inverse square law is going to drop it to background levels by two doors down.)

(Unlike the notorious US DoD/garage door punchup, wherein thousands of garage doors mysteriosly open when a stealth bomber flies over. Or a stealth bomber bombs you when you open your garage. Or something to that effect.)

Oh, nice to see you, too. It's good to put faces to names.
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