Radiated Power Question

[Robert11]

Hello:

I realize that everyone is going to probably write back and tell me I'm
crazy, but this is really driving me crazy, so let me ask, please.

I'm a retired engineer, but have never worked much with RF.

I have been putting up several models of Kidde and First Alert smoke
detectors in my new house recently.

Several different models, from both brands, both ionization and
photoelectric, some with the 9V battery, some with
the built in 10 year Li cell.

All exhibit the same performance:

About once every day or so, at totally random times, they give 3 or 4
Chirps, then nothing for approx another day or so.
This is not the indication that it gives for an actual fire; rather from the
skimpy instructions they include, an indication of needing a new battery, or
some internal fault the circuitry has discovered on its own.

All the batteries are brand new.

Here's what I'm leading up to:

About a quarter of a mile from my house, in a direct line, there's a Ham
operator with a massive mast of what must be pushing 100 feet in height.
Almost the kind you would see for a small commercial station. Has all sorts
of antenna and beams mounted to it.
I have no idea what freq's he operates at, and really don't want to ask him.

This is obviously a chap who takes his hobby seriously, and probably
radiates at the max allowable power levels, I would guess.

Is there any possibility that if he points his array at my house, it might
radiate enough power to cause my problem ?

If not, any thoughts on what else might be causing these chirps from two
different mfg's., and several models ?

Much thanks,
Bob

 

[Robert11]

Hi,

Thanks for help.

What I mean is his antenna is line-of-sight to my house, about 1/4 mile
away.

Bob
---------------------

 

[Palindrome]

Hello:

I realize that everyone is going to probably write back and tell me I'm
crazy, but this is really driving me crazy, so let me ask, please.

I'm a retired engineer, but have never worked much with RF.

I have been putting up several models of Kidde and First Alert smoke
detectors in my new house recently.

Several different models, from both brands, both ionization and
photoelectric, some with the 9V battery, some with
the built in 10 year Li cell.

All exhibit the same performance:

About once every day or so, at totally random times, they give 3 or 4
Chirps, then nothing for approx another day or so.
This is not the indication that it gives for an actual fire; rather from the
skimpy instructions they include, an indication of needing a new battery, or
some internal fault the circuitry has discovered on its own.

All the batteries are brand new.

Here's what I'm leading up to:

About a quarter of a mile from my house, in a direct line, there's a Ham
operator with a massive mast of what must be pushing 100 feet in height.
Almost the kind you would see for a small commercial station. Has all sorts
of antenna and beams mounted to it.
I have no idea what freq's he operates at, and really don't want to ask him.

This is obviously a chap who takes his hobby seriously, and probably
radiates at the max allowable power levels, I would guess.

Is there any possibility that if he points his array at my house, it might
radiate enough power to cause my problem ?

If not, any thoughts on what else might be causing these chirps from two
different mfg's., and several models ?

I live in the middle of a National Park. No mobile phone coverage. TV
only with the aerial on so high a pole the National Park won't allow it.

Mine chirp. They even chirp during power outages, when the only thing
electrical running is battery clocks. My neighbours are sheep. With the
odd pony or two. My nearest(human) neighbour is a farmer who doesn't
hold with new fangled stuff, like wireless.

They chirp with brand new batteries, too. The mains-powered one chirps
(obviously *not* during outages).

They chirp when sat on the workbench. They chirp when stuck on a ceiling
47 foot above the floor.

Doesn't everyone's?

Until you wrote, I thought they were supposed to..

 

[Robert11]

Thanks all for thoughts on this.

Would just like to re-state that for everyone, that the problem is not the
alarms indicating a fire, rather
it is a 3 or 4 chirp situation, like a low battery, or a circuitry fault,
then nothing for another day or so.

Bob

 

[Palindrome]

Thanks all for thoughts on this.

Would just like to re-state that for everyone, that the problem is not the
alarms indicating a fire, rather
it is a 3 or 4 chirp situation, like a low battery, or a circuitry fault,
then nothing for another day or so.

<snip>

Ditto. except more like 1-2 chirps, rather than 3-4.

I'd assumed that it was some form of automatic zeroing/ reset that had
to be done periodically to set a baseline and to counter drift.

 

[cupra]

I live in the middle of a National Park. No mobile phone coverage. TV
only with the aerial on so high a pole the National Park won't allow
it.
Mine chirp. They even chirp during power outages, when the only thing
electrical running is battery clocks. My neighbours are sheep. With
the odd pony or two. My nearest(human) neighbour is a farmer who
doesn't hold with new fangled stuff, like wireless.

They chirp with brand new batteries, too. The mains-powered one chirps
(obviously *not* during outages).

They chirp when sat on the workbench. They chirp when stuck on a
ceiling 47 foot above the floor.

Doesn't everyone's?

Until you wrote, I thought they were supposed to..

It's the Dartmoor faeries playing tricks on you!