| Author |
Message |
Guest
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 Posted:
Fri Jul 01, 2005 7:40 am Post subject:
46. NEWBEES, external RF transmitters disturb often Wireless |
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Don't thrust wireless alarm systems, use wired!!!
My wireless alarm system was:
- "deaf", muzzled for sensor signal reception
and
- "dead" on alarm giving
when i used a simple commercial available wireless radio headphone,
that simple ..
Its a well known radio transmission problem called "Radio Frequency
Interference" (RFI)
- present at ALL systems (old and new = external) but
- more present than normal in wireless alarm systems due to the low
power transmitters (10milliWatt) used in the sensors
AND
- the use of shared frequencies (obliged) who have disturbances and
are unprotected for RFI (see at FCC and/or other country authorities
for the world frequency band attribution scheme or www.ero.dk for
official info).
What type of signals are able to jeopardize they're operation?
External RF Transmitters operating:
- ON the wireless frequency
- Falling in the receiver band pass
- On the IF frequency (IF = Intermediate Frequency)
- Intermodulation
- Saturating the receiver front end circuit
- Harmonics
- and more...
In essence the problems caused by interference is the fact that by no
way two (or more) systems can use simultaneously the same frequency.
My wireless headphone story showed me "how simple it is" to have the
operation jeopardized completely by an external transmitter operating
on the wireless alarm frequency.
This problem is NOT REPORTED by any mean to the owner, realize what
can happen when you have a wireless FIRE detection system...
The system will no longer detect it (same for intruder alarm).
I replaced my Wireless Alarm System with a wired one; the problem is
solved for me, what about yours?
Some "extra clever pro's" say that the FCC (++) will locate and find
the disturbing signal.
1. Just realize that the local range of the disturbing signal don't
allow to locate it at distance.
2. That other legal users share the wireless alarm frequency
and that they have to find out in that bunch the one whom is
disturbing... Good luck.
Paul
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Roger
Guest
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| Posted:
Sat Jul 02, 2005 2:02 pm Post subject:
Re: 46. NEWBEES, external RF transmitters disturb often Wire |
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Newbies...
Don't trust anything this child posts.
He has ignored all of the reponses that he has been given in the past from
people who know what they are talking about. I won't bother to go through
this post and correct his mistakes yet again, but trust me he's a complete
moron with no education.
<-pull@shoot> wrote in message
news:a9b9c19k82gn2fvmvgpaot9ta1qs02v60e@4ax.com...
| Quote: |
Don't thrust wireless alarm systems, use wired!!!
My wireless alarm system was:
- "deaf", muzzled for sensor signal reception
and
- "dead" on alarm giving
when i used a simple commercial available wireless radio headphone,
that simple ..
Its a well known radio transmission problem called "Radio Frequency
Interference" (RFI)
- present at ALL systems (old and new = external) but
- more present than normal in wireless alarm systems due to the low
power transmitters (10milliWatt) used in the sensors
AND
- the use of shared frequencies (obliged) who have disturbances and
are unprotected for RFI (see at FCC and/or other country authorities
for the world frequency band attribution scheme or www.ero.dk for
official info).
What type of signals are able to jeopardize they're operation?
External RF Transmitters operating:
- ON the wireless frequency
- Falling in the receiver band pass
- On the IF frequency (IF = Intermediate Frequency)
- Intermodulation
- Saturating the receiver front end circuit
- Harmonics
- and more...
In essence the problems caused by interference is the fact that by no
way two (or more) systems can use simultaneously the same frequency.
My wireless headphone story showed me "how simple it is" to have the
operation jeopardized completely by an external transmitter operating
on the wireless alarm frequency.
This problem is NOT REPORTED by any mean to the owner, realize what
can happen when you have a wireless FIRE detection system...
The system will no longer detect it (same for intruder alarm).
I replaced my Wireless Alarm System with a wired one; the problem is
solved for me, what about yours?
Some "extra clever pro's" say that the FCC (++) will locate and find
the disturbing signal.
1. Just realize that the local range of the disturbing signal don't
allow to locate it at distance.
2. That other legal users share the wireless alarm frequency
and that they have to find out in that bunch the one whom is
disturbing... Good luck.
Paul
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Guest
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| Posted:
Sat Jul 02, 2005 2:24 pm Post subject:
Re: 46. NEWBEES, external RF transmitters disturb often Wire |
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Amazing Roger that, you say that RFI test = part of EMC testing...
Surprising.
Can you mention what part of EMC testing covers RFI?
What's certified test equipment is required to do what
YOU CALL RFI tests or is it the same certified general coverage
generators and/or power line test equipment?
Can you tell me where the answer has been given dear stupid so
"called" pro?
| Quote: | On Wed, 29 Jun 2005 18:35:16 GMT, "Roger" <rumble@myfreewebmail.com
wrote:
This is just semantics. If all that is left for you to argue is the choice
of letters used then this is the end of the thread as far as I am concerned.
I was attempting to write so that you would understand. As part of the
immunity tests carried out for EMC legislation the equipment is tested for
immunity over a wide frequency range. This is often described as RFI = Radio
Frequency Interference when the equipment fails. I have been open field EMC
testing on several occasions and it is referred to as passing or failing RFI
even though it is part of EMC immunity tests. It's a choice of words. Both
work and are understood by most.
|
On Sat, 02 Jul 2005 09:02:43 GMT, "Roger" <rumble@myfreewebmail.com>
wrote:
| Quote: | Newbies...
Don't trust anything this child posts.
He has ignored all of the reponses that he has been given in the past from
people who know what they are talking about. I won't bother to go through
this post and correct his mistakes yet again, but trust me he's a complete
moron with no education.
-pull@shoot> wrote in message
news:a9b9c19k82gn2fvmvgpaot9ta1qs02v60e@4ax.com...
Don't thrust wireless alarm systems, use wired!!!
My wireless alarm system was:
- "deaf", muzzled for sensor signal reception
and
- "dead" on alarm giving
when i used a simple commercial available wireless radio headphone,
that simple ..
Its a well known radio transmission problem called "Radio Frequency
Interference" (RFI)
- present at ALL systems (old and new = external) but
- more present than normal in wireless alarm systems due to the low
power transmitters (10milliWatt) used in the sensors
AND
- the use of shared frequencies (obliged) who have disturbances and
are unprotected for RFI (see at FCC and/or other country authorities
for the world frequency band attribution scheme or www.ero.dk for
official info).
What type of signals are able to jeopardize they're operation?
External RF Transmitters operating:
- ON the wireless frequency
- Falling in the receiver band pass
- On the IF frequency (IF = Intermediate Frequency)
- Intermodulation
- Saturating the receiver front end circuit
- Harmonics
- and more...
In essence the problems caused by interference is the fact that by no
way two (or more) systems can use simultaneously the same frequency.
My wireless headphone story showed me "how simple it is" to have the
operation jeopardized completely by an external transmitter operating
on the wireless alarm frequency.
This problem is NOT REPORTED by any mean to the owner, realize what
can happen when you have a wireless FIRE detection system...
The system will no longer detect it (same for intruder alarm).
I replaced my Wireless Alarm System with a wired one; the problem is
solved for me, what about yours?
Some "extra clever pro's" say that the FCC (++) will locate and find
the disturbing signal.
1. Just realize that the local range of the disturbing signal don't
allow to locate it at distance.
2. That other legal users share the wireless alarm frequency
and that they have to find out in that bunch the one whom is
disturbing... Good luck.
Paul
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Roger
Guest
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| Posted:
Sat Jul 02, 2005 4:36 pm Post subject:
Re: 46. NEWBEES, external RF transmitters disturb often Wire |
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| Quote: | Amazing Roger that, you say that RFI test = part of EMC testing...
Surprising.
|
Re-Read my post. I wrote the following:-
| Quote: | If you are asking how is it tested then that's a whole
document on its own. However I can tell you from experience that apart from
testing and generating a jamming signal throughtout the whole tested
spectrum as part of RFI immunity tests...
|
As you will see, I didn't say RFI test = part of EMC testing, as you seem to
suggest. I was talking about EN50131 and is DOES test for jamming as I
mentioned.
By the way, I am looking at a page that has the phrase Radio Frequency
Interference written 4 times on just one page in an EMC standard document
used in the UK (discussing the test methods used to test for radiated
immunity). So, even though you were talking about the wrong document, you
are also wrong about EMC. It does mention and talk about Radio Frequency
Interference (RFI)!!!.
| Quote: | Can you tell me where the answer has been given dear stupid so
"called" pro?
Yes. Look above numb nuts! |
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Guest
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| Posted:
Sun Jul 03, 2005 5:28 am Post subject:
Re: 46. NEWBEES, external RF transmitters disturb often Wire |
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On Sat, 02 Jul 2005 14:39:27 GMT, "Roger" <rumble@myfreewebmail.com>
wrote:
| Quote: | By the way, I am looking at a page that has the phrase Radio Frequency
Interference written 4 times on just one page in an EMC standard document
used in the UK (discussing the test methods used to test for radiated
immunity). So, even though you were talking about the wrong document, you
are also wrong about EMC. It does mention and talk about Radio Frequency
Interference (RFI)!!!.
Can you tell me where the answer has been given dear stupid so
"called" pro?
Yes. Look above numb nuts!
|
Its amazing that you can't specify the test text nor the required test
tools...
Thy just don't exist for RFI testing. |
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Roger
Guest
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| Posted:
Sun Jul 03, 2005 11:11 pm Post subject:
Re: 46. NEWBEES, external RF transmitters disturb often Wire |
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| Quote: | Its amazing that you can't specify the test text nor the required test
tools...
Thy just don't exist for RFI testing.
|
I just can't be arsed anymore. It's there. Look for yourself. I've
successfully tested wireless equipment to the standards and tests specified.
I'm not imagining them.
Well that's it. I've blocked you from my newsreader & placed a filter on
anything RFI related. No more crap from you... Wonderfull ! |
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Guest
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| Posted:
Mon Jul 04, 2005 12:36 am Post subject:
Re: 46. NEWBEES, external RF transmitters disturb often Wire |
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On Sun, 03 Jul 2005 18:11:39 GMT, "Roger" <rumble@myfreewebmail.com>
wrote:
| Quote: | Its amazing that you can't specify the test text nor the required test
tools...
Thy just don't exist for RFI testing.
I just can't be arsed anymore. It's there. Look for yourself. I've
successfully tested wireless equipment to the standards and tests specified.
I'm not imagining them.
Bye poor "low level electrician". |
There is no RFI certification, you are ignorant. |
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petem
Guest
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| Posted:
Tue Jul 05, 2005 7:47 am Post subject:
Re: 46. NEWBEES, external RF transmitters disturb often Wire |
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<-pull-@-shoot-> a écrit dans le message de news:
9smgc1lvcbjqu4opmuvb1nir6ng0h7su08@4ax.com...
| Quote: | On Sun, 03 Jul 2005 18:11:39 GMT, "Roger" <rumble@myfreewebmail.com
wrote:
Its amazing that you can't specify the test text nor the required test
tools...
Thy just don't exist for RFI testing.
I just can't be arsed anymore. It's there. Look for yourself. I've
successfully tested wireless equipment to the standards and tests
specified.
I'm not imagining them.
Bye poor "low level electrician".
There is no RFI
certification, you are ignorant.
|
paully said it...there is no RFI!!!!
LOL |
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