Receptors' range is too small for a weather station

[Merciadri Luca]

Hi,

I have a small greenhouse which is mostly constituted by plastic. I
also have a small weather station BLUESKY BWS688, with two receptors.
The manual stipulates that the working range of the receptors is ~30
meters, but I rather think that it is ~3 meters: my greenhouse is at
~5 meters, and its signal is not received. As my greenhouse is not
surrounded by some metal stuff, I would be very surprised to learn
that the Faraday effect would take place into it.

Consequently, the receptor's range seems too weak. What could I do to
solve this problem? Would it be possible to hack some antenna or some
conductor, say on one or two meters? Would it work better? I have
exchanged my two receptors, and they all work properly. Once a length
~4 meters separates the principal station and one of the receptors,
the receptor's signal is not received anymore.

Thanks.

 

[Rich Webb]

On Thu, 15 Apr 2010 03:21:19 -0700 (PDT), Merciadri Luca
<merciadriluca@gmail.com> wrote:

Hi,

I have a small greenhouse which is mostly constituted by plastic. I
also have a small weather station BLUESKY BWS688, with two receptors.
The manual stipulates that the working range of the receptors is ~30
meters, but I rather think that it is ~3 meters: my greenhouse is at
~5 meters, and its signal is not received. As my greenhouse is not
surrounded by some metal stuff, I would be very surprised to learn
that the Faraday effect would take place into it.

I'm not familiar with the construction of modern greenhouses, but it may
be that the transparent windows contain some metalization in order to
optimize the transmissive and reflective properties.

Have you tried the performance of the transmitter/receiver pairs when
they are both outside of the greenhouse?

Consequently, the receptor's range seems too weak. What could I do to
solve this problem? Would it be possible to hack some antenna or some
conductor, say on one or two meters? Would it work better? I have
exchanged my two receptors, and they all work properly. Once a length
~4 meters separates the principal station and one of the receptors,
the receptor's signal is not received anymore.

The simplest way may be to boost the antenna gain. The simplest way to
do that is probably by adding a directional reflector "behind" each
receiving antenna (and the transmitter, if the receivers can be situated
in the main lobe).

Here's one site that discusses a quick and cheap home-made version:
http://www.freeantennas.com/projects/template/

--
Rich Webb Norfolk, VA

 

[Tim Wescott]

Merciadri Luca wrote:

On Apr 15, 2:10 pm, Rich Webb <bbew...@mapson.nozirev.ten> wrote:
I'm not familiar with the construction of modern greenhouses, but it may
be that the transparent windows contain some metalization in order to
optimize the transmissive and reflective properties.
This is simple plastic, not some kind of glasses, etc.! I am doubtful
about the fact that they could contain some metalization, as they are
purely transparent.

Have you tried the performance of the transmitter/receiver pairs when
they are both outside of the greenhouse?
Yes, and it does not change anything, i.e. the greenhouse seems not to
affect the transmitter. But two meters nearer the weather station,
everything is fine.

The simplest way may be to boost the antenna gain. The simplest way to
do that is probably by adding a directional reflector "behind" each
receiving antenna (and the transmitter, if the receivers can be situated
in the main lobe).

Here's one site that discusses a quick and cheap home-made version:http://www.freeantennas.com/projects/template/
Thanks for the pointer. I would come with http://www.freeantennas.com/projects/Ez-10/pic2.JPG,
but the problem is that my two small receivers (which compute the
temperature around them) have no `outgoing' antenna, and I thus do not
know if the antenna is at their top, their bottom, `behind' or `in
front' of them. And if I put some metal around the whole receiver, the
Faraday effect will annihilate all our chances!

Make a parabolic reflector (it doesn't have to be executed very well --
tin foil and cardboard would do), with the whole unit at the focus,
pointed at the base station.

See if it works.

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

 

[Merciadri Luca]

On Apr 15, 2:10 pm, Rich Webb <bbew...@mapson.nozirev.ten> wrote:

I'm not familiar with the construction of modern greenhouses, but it may
be that the transparent windows contain some metalization in order to
optimize the transmissive and reflective properties.
This is simple plastic, not some kind of glasses, etc.! I am doubtful

about the fact that they could contain some metalization, as they are
purely transparent.

Have you tried the performance of the transmitter/receiver pairs when
they are both outside of the greenhouse?
Yes, and it does not change anything, i.e. the greenhouse seems not to

affect the transmitter. But two meters nearer the weather station,
everything is fine.

The simplest way may be to boost the antenna gain. The simplest way to
do that is probably by adding a directional reflector "behind" each
receiving antenna (and the transmitter, if the receivers can be situated
in the main lobe).

Here's one site that discusses a quick and cheap home-made version:http://www.freeantennas.com/projects/template/
Thanks for the pointer. I would come with http://www.freeantennas.com/projects/Ez-10/pic2.JPG,

but the problem is that my two small receivers (which compute the
temperature around them) have no `outgoing' antenna, and I thus do not
know if the antenna is at their top, their bottom, `behind' or `in
front' of them. And if I put some metal around the whole receiver, the
Faraday effect will annihilate all our chances!

 

[ehsjr]

Merciadri Luca wrote:

On Apr 15, 2:10 pm, Rich Webb <bbew...@mapson.nozirev.ten> wrote:

I'm not familiar with the construction of modern greenhouses, but it may
be that the transparent windows contain some metalization in order to
optimize the transmissive and reflective properties.

This is simple plastic, not some kind of glasses, etc.! I am doubtful
about the fact that they could contain some metalization, as they are
purely transparent.


Have you tried the performance of the transmitter/receiver pairs when
they are both outside of the greenhouse?

Yes, and it does not change anything, i.e. the greenhouse seems not to
affect the transmitter. But two meters nearer the weather station,
everything is fine.


The simplest way may be to boost the antenna gain. The simplest way to
do that is probably by adding a directional reflector "behind" each
receiving antenna (and the transmitter, if the receivers can be situated
in the main lobe).

Here's one site that discusses a quick and cheap home-made version:http://www.freeantennas.com/projects/template/

Thanks for the pointer. I would come with http://www.freeantennas.com/projects/Ez-10/pic2.JPG,
but the problem is that my two small receivers (which compute the
temperature around them) have no `outgoing' antenna, and I thus do not
know if the antenna is at their top, their bottom, `behind' or `in
front' of them. And if I put some metal around the whole receiver, the
Faraday effect will annihilate all our chances!

| |
Reflector=>| Sensor Station |<=Reflector
| |

The antenna is inside the remote temperature sensor. It does
not matter where the antenna is inside the sensor, but make
sure that both the sensor and the station stand upright, and
have new batteries. BTW what you are calling a "receiver" is
actually a transmitter. It detects the temperature around
itself, and transmits that information to your weather
station display.

I have 2 different brands of wireless thermometers. With
both brands, laying the devices horizontal affects the
range. Height above ground may play a role, depending
on environment. Also, it is possible there is another
source of RF signal nearby that is de-sensing the receiver
inside the display station.

Ed

 

[Michael Black]

On Thu, 15 Apr 2010, Merciadri Luca wrote:

Hi,

I have a small greenhouse which is mostly constituted by plastic. I
also have a small weather station BLUESKY BWS688, with two receptors.
The manual stipulates that the working range of the receptors is ~30
meters, but I rather think that it is ~3 meters: my greenhouse is at
~5 meters, and its signal is not received. As my greenhouse is not
surrounded by some metal stuff, I would be very surprised to learn
that the Faraday effect would take place into it.

Are you out on a farm, or in some high density area? If the latter, it

increases the chances that some other device is using the same frequency
for something, and thus blocking the desired signal unless it's close
enough to be strong.

The same frequency is reused for various devices, it's even mildly
possible that you might have something else that is using the frequency.

Michael

 

[Merciadri Luca]

Thanks for all your answers.

On Apr 15, 9:38 pm, Michael Black <et...@ncf.ca> wrote:

On Thu, 15 Apr 2010, Merciadri Luca wrote:
Hi,

I have a small greenhouse which is mostly constituted by plastic. I
also have a small weather station BLUESKY BWS688, with two receptors.
The manual stipulates that the working range of the receptors is ~30
meters, but I rather think that it is ~3 meters: my greenhouse is at
~5 meters, and its signal is not received. As my greenhouse is not
surrounded by some metal stuff, I would be very surprised to learn
that the Faraday effect would take place into it.

Are you out on a farm, or in some high density area?  If the latter, it
increases the chances that some other device is using the same frequency
for something, and thus blocking the desired signal unless it's close
enough to be strong.
The same frequency is reused for various devices, it's even mildly
possible that you might have something else that is using the frequency.
Not at all. I am in a small village, but not in a farm. The house is

normal, and there is no reinforced concrete. There is a maximum of 2
or 3 wireless networks.

Both *transmitters* (sorry for the bad name), as `ehsjr' explained it,
have brand new batteries.

I will do a parabolic antenna tomorrow. I'll let you know. Thanks for
your help.

 

[Merciadri Luca]

On Apr 15, 11:35 pm, Merciadri Luca <merciadril...@gmail.com> wrote:

Thanks for all your answers.

On Apr 15, 9:38 pm, Michael Black <et...@ncf.ca> wrote:

On Thu, 15 Apr 2010, Merciadri Luca wrote:
Hi,

I have a small greenhouse which is mostly constituted by plastic. I
also have a small weather station BLUESKY BWS688, with two receptors.
The manual stipulates that the working range of the receptors is ~30
meters, but I rather think that it is ~3 meters: my greenhouse is at
~5 meters, and its signal is not received. As my greenhouse is not
surrounded by some metal stuff, I would be very surprised to learn
that the Faraday effect would take place into it.

Are you out on a farm, or in some high density area?  If the latter, it
increases the chances that some other device is using the same frequency
for something, and thus blocking the desired signal unless it's close
enough to be strong.
The same frequency is reused for various devices, it's even mildly
possible that you might have something else that is using the frequency..

Not at all. I am in a small village, but not in a farm. The house is
normal, and there is no reinforced concrete. There is a maximum of 2
or 3 wireless networks.

Both *transmitters* (sorry for the bad name), as `ehsjr' explained it,
have brand new batteries.

I will do a parabolic antenna tomorrow. I'll let you know. Thanks for
your help.
Okay, I did it, and it drastically improved the transmitter's range.

Actually, the other transmitter seems not to work. It seems to be
defective. I opened it, checked the selfs, etc., and everything seems
normal, at first sight.

 

[ehsjr]

Merciadri Luca wrote:

On Apr 15, 11:35 pm, Merciadri Luca <merciadril...@gmail.com> wrote:

Thanks for all your answers.

On Apr 15, 9:38 pm, Michael Black <et...@ncf.ca> wrote:


On Thu, 15 Apr 2010, Merciadri Luca wrote:

Hi,

I have a small greenhouse which is mostly constituted by plastic. I
also have a small weather station BLUESKY BWS688, with two receptors.
The manual stipulates that the working range of the receptors is ~30
meters, but I rather think that it is ~3 meters: my greenhouse is at
~5 meters, and its signal is not received. As my greenhouse is not
surrounded by some metal stuff, I would be very surprised to learn
that the Faraday effect would take place into it.

Are you out on a farm, or in some high density area? If the latter, it
increases the chances that some other device is using the same frequency
for something, and thus blocking the desired signal unless it's close
enough to be strong.
The same frequency is reused for various devices, it's even mildly
possible that you might have something else that is using the frequency.

Not at all. I am in a small village, but not in a farm. The house is
normal, and there is no reinforced concrete. There is a maximum of 2
or 3 wireless networks.

Both *transmitters* (sorry for the bad name), as `ehsjr' explained it,
have brand new batteries.

I will do a parabolic antenna tomorrow. I'll let you know. Thanks for
your help.

Okay, I did it, and it drastically improved the transmitter's range.
Actually, the other transmitter seems not to work. It seems to be
defective. I opened it, checked the selfs, etc., and everything seems
normal, at first sight.

You may need to set the second transmitter to a different channel.

Ed

 

[Phil Allison]

"ehsjr"

You may need to set the second transmitter to a different channel.

** These sorts of devices do not have the ability to select "channels" -
the transmitters send brief bursts of data once every 5 or 10 seconds and
all use the same radio frequency.

Wireless door bells have the facility to alter modulation CODES so that the
receiver only responds to the matching transmitter - but if two nearby
transmitters are operated simultaneously, then likely neither bell will
ring.



..... Phil

 

[ehsjr]

Phil Allison wrote:

"ehsjr"



You may need to set the second transmitter to a different channel.



** These sorts of devices do not have the ability to select "channels" -

Mine do. There's a switch in the battery compartment of the
transmitters to select channel 1 or 2 or 3.
Here's a reference:
http://www.amazon.com/Oregon-Scientific-Wireless-Temperature-Sensor/dp/B000I2Q1P8/ref=pd_sim_dbs_k_1

Quoting from the page:
Product Features

* Remote, wireless thermometer for Oregon Scientific weather stations
* Transmits up to 100 feet from the main unit; requires 1 AA battery
* Water-resistant casing and a battery cover
* Sets to one of three different channels for tandem transmissions
with other sensors
* Red LED light notifies when data transmission has been sent

End quote

the transmitters send brief bursts of data once every 5 or 10 seconds and
all use the same radio frequency.

Right. But the instruction manual refers to transmission
and reception of 3 channels, and the display shows the
letters "CH" followed by the number of the channel it
is monitoring.

The other unit I have is a La Crosse
http://www.lacrosseweatherandmore.com/IVG2/N/ProductID-80574.htm
which also can receive from up to 3 sensors. La Crosse also refers
to channels which are selected by a button on the front of the
display labelled SET and CH.

Ed

Wireless door bells have the facility to alter modulation CODES so that the
receiver only responds to the matching transmitter - but if two nearby
transmitters are operated simultaneously, then likely neither bell will
ring.



.... Phil

 

[Phil Allison]

"ehsjr"
Phil Allison

You may need to set the second transmitter to a different channel.

** These sorts of devices do not have the ability to select "channels" -

Mine do.

** Not separate radio frequency channels they don't.

There's a switch in the battery compartment of the
transmitters to select channel 1 or 2 or 3.

** Just alters the data code to signal which sensor it is.

the transmitters send brief bursts of data once every 5 or 10 seconds and
all use the same radio frequency.

Right. But the instruction manual refers to transmission
and reception of 3 channels, and the display shows the
letters "CH" followed by the number of the channel it
is monitoring.

** Makers can call a feature whatever they like.

The term "channel" is far more easily grasped by the non-technical public.



Wireless door bells have the facility to alter modulation CODES so that the
receiver only responds to the matching transmitter - but if two nearby
transmitters are operated simultaneously, then likely neither bell will
ring.

The different codes use are often referred to as "channels" - ie 1,2,3, 4
or A,B,C,D.



.... Phil

 

[Merciadri Luca]

On Apr 17, 6:08 am, ehsjr <eh...@nospamverizon.net> wrote:

Phil Allison wrote:
"ehsjr"

You may need to set the second transmitter to a different channel.

** These sorts of devices do not have the ability to select "channels" -

Mine do. There's a switch in the battery compartment of the
transmitters to select channel 1 or 2 or 3.
Here's a reference:http://www.amazon.com/Oregon-Scientific-Wireless-Temperature-Sensor/d...

Quoting from the page:
Product Features

     * Remote, wireless thermometer for Oregon Scientific weather stations
     * Transmits up to 100 feet from the main unit; requires 1 AA battery
     * Water-resistant casing and a battery cover
     * Sets to one of three different channels for tandem transmissions
with other sensors
     * Red LED light notifies when data transmission has been sent

End quote

the transmitters send brief bursts of data once every 5 or 10 seconds and
all use the same radio frequency.

Right. But the instruction manual refers to transmission
and reception of 3 channels, and the display shows the
letters "CH" followed by the number of the channel it
is monitoring.

The other unit I have is a La Crossehttp://www.lacrosseweatherandmore.com/IVG2/N/ProductID-80574.htm
which also can receive from up to 3 sensors. La Crosse also refers
to channels which are selected by a button on the front of the
display labelled SET and CH.

Ed



Wireless door bells have the facility to alter modulation CODES  so that the
receiver only responds to the matching transmitter  - but if two nearby
transmitters are operated simultaneously, then likely neither bell will
ring.

....  Phil

BLUESKY is quite like some noname products. It consequently does not
surprise me to see that there is no possibility to switch channels,
etc. for the transmitters. Any idea why one of my two transmitters
does not work?

Thanks.