What About The ISS?

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Re: What About The ISS?
« Reply #90 on: June 29, 2015, 04:28:14 PM »
You don't even need 1mA . Volts alone is sufficient if you have a magnesium deficiency or other form of electrolyte imbalance .
When it comes to Jane's standards .I'm lower then an old stove she has in her garage.
Shannon Noll and Natalie Bassingthwaighte - Don't…:

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Yendor

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Re: What About The ISS?
« Reply #91 on: June 29, 2015, 04:42:36 PM »
You don't even need 1mA . Volts alone is sufficient if you have a magnesium deficiency or other form of electrolyte imbalance .


Which I do.
"During times of universal deceit, telling the truth becomes a revolutionary act."
                              George Orwell

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Mikey T.

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Re: What About The ISS?
« Reply #92 on: June 29, 2015, 04:54:50 PM »
Voltage is not what will kill you.  But, with high voltage and a low body resistance you can actually get a high enough current to flow through your body to possibly kill you.  It is rather rare to see a body with a low enough resistance to actually have all the factors in place for such a thing to do, and it still needs to cross your heart.  So I guess i am sorta agreeing with charles on this.  Crap, I need to go wash my hands, I feel dirty now.

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Yendor

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Re: What About The ISS?
« Reply #93 on: June 29, 2015, 05:04:19 PM »
Nope, not gonna acid etch my on boards, if this is what you are referring to on the tape.  I have used a copper mill to cut double sided boards.  I usually just lay out the boards after fighting wires and through pin chips on a breadboard, then lay out the circuit board in Eagle (BTW they have a huge downloadable library of actual footprints for the parts if you know what specific ones you are using, or you can design your own library if you can't find one, I had to for some surface mount atmel chips), adding any layers to reduce the size of the board, then once I am satisfied and it passes the emulation testing I export it to a layout file and submit it to Osha Park.  They are very friendly to small scale operations such as prototyping boards.  Cheaper to order enough to fill a 10 by 20 inch sheet though. 
Cadsoft make Eagle, you can check them out here, but I am not sure how scaled down the trial software may be.  I think it will only let you make something like a 2 inch by 2 inch board.  Also another decent free CAD circuit program is PSpice.  This is what almost of the circuits I had to design in school used to emulate it, but i do not think is hase board layout tools, not sure on that, but i prefer it for testing initial circuit ideas so you can get an ideal readings for any node in the circuit.

Mikey T.,

I always use a company called ExpressPCB for prototype boards I did at home. They have a free program you design the schematic with and another free program that  does the actual board. You should check them out. I believe this is the first time you've been civil to me. Thanks.

Yendor
Not completely true there, we had a nice conversation about atmospheric bounce and the frequencies that the ionosphere would reflect.  I think your point was that the Satellite signals could bounce back, and mine was that microwaves were too short a wavelength to do so. 
modestman, please stray away from the conversation, as you have no idea what you are talking about.
But yes Yendor, I will try to be more civil towards you.  Like I said, I sacrificed way too much to see engineering get crapped on.  Whether you were intending on that being your message or not, I took it that way.

Mikey T.

Yes we did, I now remember that. I was basically saying that it is possible to bounce waves off the ionosphere that was in the Ghz range. It depended on the angle  of the wave. Basically the wider the angle the higher the frequency. Most of what you read says 30mhz is the limit. Any higher the signal would pass through the ionosphere. The point I was trying to make was if you aimed a dish at that point in the sky you would be able to receive the TV signal. Not from a satellite but from the sky. It was an old research paper that was written long before satellites came into existence. I know I was very surprised  when I read it. I know when I was young I had an old CB transceiver and I could talk skip on a lot of nights.

I feel the same about electronics as you do. I knew when I was very young I wanted to learn about TVs. When the TV service man came to our house to replace a tube I couldn't wait until I could see inside when he took the back off. My whole life has been working on cars, Mechanical design and electronic design. Good talking with you.

Yendor

Yendor
"During times of universal deceit, telling the truth becomes a revolutionary act."
                              George Orwell

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Mikey T.

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Re: What About The ISS?
« Reply #94 on: June 29, 2015, 05:05:12 PM »
Since we are talking all nice to each other, I will give you a hint as to my current roadblock on one of my designs.  I am trying to initiate a large enough current from a door opening as to send a signal to a base station without the use of a battery or power supply.  I have tried high rated capacitors, I am just having some issues with the inductive charge of a magnetic strip moving against another one to form enough charge.  I am looking at using two semiconductors an N and a P with them making contact when the door is closed but when it is open the charge should build due to the gap between them.  However, if I could use the door being closed in a way to keep an air gap between the two then they make momentary contact as the door opens, I can create a larger charge to be sent from the N material to the cap and thus enough charge to send a signal burst out to the base unit. 
I would rather keep it in the magnetic induction type model as the lifetime of the device would increase and my costs would go down.  Much better compromise, but as of yet I have not been able to get enough charge to initiate the signal in a way that can be picked up at the base unit.

Re: What About The ISS?
« Reply #95 on: June 29, 2015, 05:07:50 PM »
There are two options of microwave:
1)they are not bumping any signals through the ionosphere - it's simple long range waves and there is no curvature
2)they bump it through the upper earth, the earth above us which its bottom is what we call the firmament or dome.

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Mikey T.

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Re: What About The ISS?
« Reply #96 on: June 29, 2015, 05:10:09 PM »
True enough, but 30kHz is the very upper limit for a signal bounce, it works much better down in the 10 kHz range.  The signal being received at the dish is in fact in the Ka to Ku band though meaning between the 12 to 30ish GHz.  Although the middle of the K band is right at the resonant frequency of water, so anything with a wide enough rain droplet as to be a bit above 1 cm gets absorbed by the rain droplet.  The more rain, the more signal gets absorbed, i.e. Rain fade for satellites. 
But no need to go back into that discussion here, I think we both left that one on good terms.

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Yendor

  • 1676
Re: What About The ISS?
« Reply #97 on: June 29, 2015, 05:14:00 PM »
Voltage is not what will kill you.  But, with high voltage and a low body resistance you can actually get a high enough current to flow through your body to possibly kill you.  It is rather rare to see a body with a low enough resistance to actually have all the factors in place for such a thing to do, and it still needs to cross your heart.  So I guess i am sorta agreeing with charles on this.  Crap, I need to go wash my hands, I feel dirty now.

Mikey T.,

The current doesn't have to be that high. Just 1mA or less can cause your heart to stop, If the current passes you heart.

Yendor
"During times of universal deceit, telling the truth becomes a revolutionary act."
                              George Orwell

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Yendor

  • 1676
Re: What About The ISS?
« Reply #98 on: June 29, 2015, 05:15:51 PM »
True enough, but 30kHz is the very upper limit for a signal bounce, it works much better down in the 10 kHz range.  The signal being received at the dish is in fact in the Ka to Ku band though meaning between the 12 to 30ish GHz.  Although the middle of the K band is right at the resonant frequency of water, so anything with a wide enough rain droplet as to be a bit above 1 cm gets absorbed by the rain droplet.  The more rain, the more signal gets absorbed, i.e. Rain fade for satellites. 
But no need to go back into that discussion here, I think we both left that one on good terms.

Right you are.
"During times of universal deceit, telling the truth becomes a revolutionary act."
                              George Orwell

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Mikey T.

  • 3545
Re: What About The ISS?
« Reply #99 on: June 29, 2015, 05:17:16 PM »
There are two options of microwave:
1)they are not bumping any signals through the ionosphere - it's simple long range waves and there is no curvature
2)they bump it through the upper earth, the earth above us which its bottom is what we call the firmament or dome.
Well they do not work that way.  The receiving antenna has to be precisely pointed at one spot in the sky, and you can actually play around with blocking it from every side except directly in the signal path.  This will show it to be a LOS signal.  Meaning it is on a straight path from the sky.  This rules out terrestrial broadcast direct to the receiver. 
As far as bouncing it, using geometry, you would not be able to have all Receiver dishes point at the same relative spot in the sky to receive it unless you have almost as many broadcast locations situated all over the place.  When i was working for them, I could set up two dishes around 100 miles apart and have a very very similar setup on both.  This means the location is relatively far away.  With a bounce effect I would need two separate broadcast locations to hit these two receiving locations. 
Sorry, it has been proposed before, but just will not work.   

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Rayzor

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Re: What About The ISS?
« Reply #100 on: June 29, 2015, 05:20:36 PM »
Since we are talking all nice to each other, I will give you a hint as to my current roadblock on one of my designs.  I am trying to initiate a large enough current from a door opening as to send a signal to a base station without the use of a battery or power supply.  I have tried high rated capacitors, I am just having some issues with the inductive charge of a magnetic strip moving against another one to form enough charge.  I am looking at using two semiconductors an N and a P with them making contact when the door is closed but when it is open the charge should build due to the gap between them.  However, if I could use the door being closed in a way to keep an air gap between the two then they make momentary contact as the door opens, I can create a larger charge to be sent from the N material to the cap and thus enough charge to send a signal burst out to the base unit. 
I would rather keep it in the magnetic induction type model as the lifetime of the device would increase and my costs would go down.  Much better compromise, but as of yet I have not been able to get enough charge to initiate the signal in a way that can be picked up at the base unit.

Good to see Yendor come clean at last.    I'd stick with the magnets and coils  ( aka generator ) design for your door,  but I'd put it over on the hinge line where you have a mechanical advantage and gear it up to spin a little generator.   If you are looking for small generators,  try testing some small low voltage dc motors.   

For PCB design,  we used Altium  ( used to be protel )  for years,  since I retired I do consulting work,  when the job is interesting enough, and the money worth while.  So I still use Altium,  and I get boards made in china,  4 layer boards,  excellent quality,  unbelievable prices,  and quick turnaround.    All smt these days,  and enough 0.5mm pitch ic's to test the eyesight to the limit.

Yendor, 

I'm still waiting for you to tell me what part of the solar panel the astronaut would get a shock from.   Also waiting on a citation for the 1ma can kill claim. 
When you've answered those questions,  you can tell me why you think the ISS is fake,   but I want to see evidence to support your belief.


Stop gilding the pickle, you demisexual aromantic homoflexible snowflake.

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Mikey T.

  • 3545
Re: What About The ISS?
« Reply #101 on: June 29, 2015, 05:27:01 PM »
Voltage is not what will kill you.  But, with high voltage and a low body resistance you can actually get a high enough current to flow through your body to possibly kill you.  It is rather rare to see a body with a low enough resistance to actually have all the factors in place for such a thing to do, and it still needs to cross your heart.  So I guess i am sorta agreeing with charles on this.  Crap, I need to go wash my hands, I feel dirty now.

Mikey T.,

The current doesn't have to be that high. Just 1mA or less can cause your heart to stop, If the current passes you heart.

Yendor
I have to disagree with you on the figure there slightly.  it really needs to be closer to 10mA before your muscles cannot operate.  That being said, I think with the heart it could probably, with a defective or "older" heart, maybe get down to 5mA crossing the heart to stop it from beating.  I only say this as the heart muscle is pretty finely tuned (thanks God, its a genius machine).
But we are splitting hairs to a point.  The more resistance your body has the lower the current will be as it gets closer to the core of your body, i.e. heart muscle.  This depends on the path it takes also as the path the electricity will take would be the least resistance one, if that is through your arm down to your foot, it most likely wont cross your heart if the current is not really high. 
Current is just moving of electrons, this one pushing that one out of its location, leaving a positive or no charge to be more specific, so on and so forth.  The easier it is to push the next electron out of its "area" the higher the current will be and it will move in that direction.

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Mikey T.

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Re: What About The ISS?
« Reply #102 on: June 29, 2015, 05:35:05 PM »
Well I am trying to "dummy proof' a device to be attached to the door and door frame.  I want the skill level for the installation to be rather low end as it were. 
Not to get too in depth in the design, I am working on making a DIY kit for home automation.  The system can work with cameras, lighting control and security.  I have everything from the cellphone app to the base units for everything prototyped and working pretty well except for the door and window intrusion devices. 
Once I can hammer that part down and be low impact enough, i.e. aesthetics, I will take it to the next step of trying to get backing.  I am toying with the kickstarter idea, but I prefer to have my designs protected first.  So gotta make it work, then submit the finished designs etc. 
 
edit**  So what is patent worthy of my designs, well think of the embedded system being in the base unit being modular.  And there is a bit in the signals being used and how the embedded system provides security on those signals.
« Last Edit: June 29, 2015, 05:43:41 PM by Mikey T. »

Re: What About The ISS?
« Reply #103 on: June 29, 2015, 05:40:43 PM »
Since we are talking all nice to each other, I will give you a hint as to my current roadblock on one of my designs.  I am trying to initiate a large enough current from a door opening as to send a signal to a base station without the use of a battery or power supply.  I have tried high rated capacitors, I am just having some issues with the inductive charge of a magnetic strip moving against another one to form enough charge.  I am looking at using two semiconductors an N and a P with them making contact when the door is closed but when it is open the charge should build due to the gap between them.  However, if I could use the door being closed in a way to keep an air gap between the two then they make momentary contact as the door opens, I can create a larger charge to be sent from the N material to the cap and thus enough charge to send a signal burst out to the base unit. 
I would rather keep it in the magnetic induction type model as the lifetime of the device would increase and my costs would go down.  Much better compromise, but as of yet I have not been able to get enough charge to initiate the signal in a way that can be picked up at the base unit.

Good to see Yendor come clean at last.    I'd stick with the magnets and coils  ( aka generator ) design for your door,  but I'd put it over on the hinge line where you have a mechanical advantage and gear it up to spin a little generator.   If you are looking for small generators,  try testing some small low voltage dc motors.   

For PCB design,  we used Altium  ( used to be protel )  for years,  since I retired I do consulting work,  when the job is interesting enough, and the money worth while.  So I still use Altium,  and I get boards made in china,  4 layer boards,  excellent quality,  unbelievable prices,  and quick turnaround.    All smt these days,  and enough 0.5mm pitch ic's to test the eyesight to the limit.

Yendor, 

I'm still waiting for you to tell me what part of the solar panel the astronaut would get a shock from.   Also waiting on a citation for the 1ma can kill claim. 
When you've answered those questions,  you can tell me why you think the ISS is fake,   but I want to see evidence to support your belief.
people lies a lot, a lot, look at news, why NAZA wouldn't lie ?

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Rayzor

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Re: What About The ISS?
« Reply #104 on: June 29, 2015, 05:43:35 PM »
Well I am trying to "dummy proof' a device to be attached to the door and door frame.  I want the skill level for the installation to be rather low end as it were. 
Not to get too in depth in the design, I am working on making a DIY kit for home automation.  The system can work with cameras, lighting control and security.  I have everything from the cellphone app to the base units for everything prototyped and working pretty well except for the door and window intrusion devices. 
Once I can hammer that part down and be low impact enough, i.e. aesthetics, I will take it to the next step of trying to get backing.  I am toying with the kickstarter idea, but I prefer to have my designs protected first.  So gotta make it work, then submit the finished designs etc.

There is plenty of mechanical energy there,  so it's just a matter of coming up with a means of converting enough to power a small transmitter,   I have seen designs for piezo clickers that transmit car door type rolling codes,   and an IR one I think? 

Here ..
http://techon.nikkeibp.co.jp/english/NEWS_EN/20091117/177713/

As the door or window opens it clicks the piezo and transmits the code.    Well,  it's an idea ;D

Stop gilding the pickle, you demisexual aromantic homoflexible snowflake.

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sokarul

  • 19303
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Re: What About The ISS?
« Reply #105 on: June 29, 2015, 05:44:13 PM »
Since we are talking all nice to each other, I will give you a hint as to my current roadblock on one of my designs.  I am trying to initiate a large enough current from a door opening as to send a signal to a base station without the use of a battery or power supply.  I have tried high rated capacitors, I am just having some issues with the inductive charge of a magnetic strip moving against another one to form enough charge.  I am looking at using two semiconductors an N and a P with them making contact when the door is closed but when it is open the charge should build due to the gap between them.  However, if I could use the door being closed in a way to keep an air gap between the two then they make momentary contact as the door opens, I can create a larger charge to be sent from the N material to the cap and thus enough charge to send a signal burst out to the base unit. 
I would rather keep it in the magnetic induction type model as the lifetime of the device would increase and my costs would go down.  Much better compromise, but as of yet I have not been able to get enough charge to initiate the signal in a way that can be picked up at the base unit.
ummm can't just do a gear setup like this?
http://techxplore.com/news/2015-06-students-germ-free-door.html
ANNIHILATOR OF  SHIFTER

It's no slur if it's fact.

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Mikey T.

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Re: What About The ISS?
« Reply #106 on: June 29, 2015, 05:46:24 PM »
Exactly piezoelectric is what I am looking at currently with the N and P materials portion. 
http://www.news.gatech.edu/features/harvesting-worlds-mechanical-energy

Sok, I haven't looked into replacing the hardware on the door like that yet.  Interesting option though, I will have to read that completely, I just skimmed it for a minute or so.
** edited a typo
« Last Edit: June 29, 2015, 05:49:08 PM by Mikey T. »

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sokarul

  • 19303
  • Extra Racist
Re: What About The ISS?
« Reply #107 on: June 29, 2015, 05:49:14 PM »
Exactly piezo is what I am looking at currently with the N and P materials portion. 
http://www.news.gatech.edu/features/harvesting-worlds-mechanical-energy

Sok, I haven't looked into replacing the hardware on the door like that yet.  interesting option though, I will have to read that completely, I just skimmed it for a minute or so.
It doesn't say how to do it, they just supposedly have enough power from the door's movement to power a UV light.
ANNIHILATOR OF  SHIFTER

It's no slur if it's fact.

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Rayzor

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Re: What About The ISS?
« Reply #108 on: June 29, 2015, 05:53:06 PM »
Exactly piezo is what I am looking at currently with the N and P materials portion. 
http://www.news.gatech.edu/features/harvesting-worlds-mechanical-energy

Sok, I haven't looked into replacing the hardware on the door like that yet.  interesting option though, I will have to read that completely, I just skimmed it for a minute or so.

Interesting idea for a door handle,   could be a winner for hospitals and nursing homes and the like. 

TI have an energy harvesting kit,   http://au.mouser.com/applications/energy_harvesting_solar/     might give you some ideas about low light level solar panels.   You can get solar panels that will work with very low ambient light levels.
Stop gilding the pickle, you demisexual aromantic homoflexible snowflake.

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Mikey T.

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Re: What About The ISS?
« Reply #109 on: June 29, 2015, 05:58:22 PM »
Well, I did look into having the door's movement charge a capacitor over time, but if I could just get enough current off of just one door opening event, then I could just keep all the intrusion detection being done safely at the base station and the door or window device would not have to know whether or not it was armed or not.  Windows would be easier to a point using a small solar cell and a standard contact strip.  Excuse the pun, but I am stuck in the doorway area.

Re: What About The ISS?
« Reply #110 on: June 29, 2015, 06:01:38 PM »
JROA please stop their spamming.

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Rayzor

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Re: What About The ISS?
« Reply #111 on: June 29, 2015, 06:11:53 PM »
Well, I did look into having the door's movement charge a capacitor over time, but if I could just get enough current off of just one door opening event, then I could just keep all the intrusion detection being done safely at the base station and the door or window device would not have to know whether or not it was armed or not.  Windows would be easier to a point using a small solar cell and a standard contact strip.  Excuse the pun, but I am stuck in the doorway area.

I think it's going to be a case of build a few prototypes,  starting with the lowest power transmitter and microcontroller you can get away with,  and then coming up with the energy harvesting system that fits the product profile.    Just as an aside are you familiar with microchip's  keeloq product range?
Stop gilding the pickle, you demisexual aromantic homoflexible snowflake.

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Mikey T.

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Re: What About The ISS?
« Reply #112 on: June 29, 2015, 06:26:14 PM »
As for Keeloq, very little. 
I do have to have enough power to get beyond the noise, i.e. EMI and RFI that may be in the range of low power signals.  I also have to have an ID in the signal to be able to differentiate what access point has been triggered. 
Like I said, it is a work in progress, I have tried several different versions.

modestman, I am sorry if this is boring to you, or you cannot understand what we are talking about.  Yes we have diverged  a great deal from the OP.  So I will try to back out of the conversation.  This is just what is currently on my mind fairly heavily for while i am not at work.  It is nice to get others opinions too.

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Rayzor

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Re: What About The ISS?
« Reply #113 on: June 29, 2015, 06:30:15 PM »
As for Keeloq, very little. 
I do have to have enough power to get beyond the noise, i.e. EMI and RFI that may be in the range of low power signals.  I also have to have an ID in the signal to be able to differentiate what access point has been triggered. 
Like I said, it is a work in progress, I have tried several different versions.

modestman, I am sorry if this is boring to you, or you cannot understand what we are talking about.  Yes we have diverged  a great deal from the OP.  So I will try to back out of the conversation.  This is just what is currently on my mind fairly heavily for while i am not at work.  It is nice to get others opinions too.

modestman just wants to get back to insulting everyone.   I'd ignore him.

My current consulting work is the opposite end of the scale,  at least as far as power is concerned,  it's designing 10 KW off grid solar systems.   

Stop gilding the pickle, you demisexual aromantic homoflexible snowflake.

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guv

  • 1132
Re: What About The ISS?
« Reply #114 on: June 29, 2015, 08:17:29 PM »
As for Keeloq, very little. 
I do have to have enough power to get beyond the noise, i.e. EMI and RFI that may be in the range of low power signals.  I also have to have an ID in the signal to be able to differentiate what access point has been triggered. 
Like I said, it is a work in progress, I have tried several different versions.

modestman, I am sorry if this is boring to you, or you cannot understand what we are talking about.  Yes we have diverged  a great deal from the OP.  So I will try to back out of the conversation.  This is just what is currently on my mind fairly heavily for while i am not at work.  It is nice to get others opinions too.

modestman just wants to get back to insulting everyone.   I'd ignore him.

My current consulting work is the opposite end of the scale,  at least as far as power is concerned,  it's designing 10 KW off grid solar systems.


Don't tell Tony Rabbit you do solar. Want an offsider?.

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Yendor

  • 1676
Re: What About The ISS?
« Reply #115 on: June 30, 2015, 08:02:56 AM »
Since we are talking all nice to each other, I will give you a hint as to my current roadblock on one of my designs.  I am trying to initiate a large enough current from a door opening as to send a signal to a base station without the use of a battery or power supply.  I have tried high rated capacitors, I am just having some issues with the inductive charge of a magnetic strip moving against another one to form enough charge.  I am looking at using two semiconductors an N and a P with them making contact when the door is closed but when it is open the charge should build due to the gap between them.  However, if I could use the door being closed in a way to keep an air gap between the two then they make momentary contact as the door opens, I can create a larger charge to be sent from the N material to the cap and thus enough charge to send a signal burst out to the base unit. 
I would rather keep it in the magnetic induction type model as the lifetime of the device would increase and my costs would go down.  Much better compromise, but as of yet I have not been able to get enough charge to initiate the signal in a way that can be picked up at the base unit.

Mikey T.

Why not use the same kind of device they use for tool roads. In my are it called EZPass. The device in the car has no battery. The device sends out an RF signal that turns on the device in the car and then the device transmits a digital signal over an RF carrier that transmits the persons info to the control center. The distance these devices work is pretty far. In fact you can wire an entire factory using this method. If this won't work, give me more information of your requirement.

Yendor
"During times of universal deceit, telling the truth becomes a revolutionary act."
                              George Orwell

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Yendor

  • 1676
Re: What About The ISS?
« Reply #116 on: June 30, 2015, 08:17:45 AM »

Yendor, 

I'm still waiting for you to tell me what part of the solar panel the astronaut would get a shock from.   Also waiting on a citation for the 1ma can kill claim. 
When you've answered those questions,  you can tell me why you think the ISS is fake,   but I want to see evidence to support your belief.
[/quote]


Rayzor,

Jimmy,

If a body resistance is low enough and 1mA could pass through his heart a person could die. Especially those with weak hearts. I never said,"if you get shocked for 1 second 1mA would kill you". I simply said, "1ma for one second can kill". A bright guy like yourself should have figured that out.

Have you read were solar panels produce voltage yet? If it is true you work around solar panels on do something with them, You should realize if you touch the negative and positive lead of a high wattage solar panel you could get shocked. If I'm wrong please explain why. I only expect it to happen. I've never worked with them at all.

Yendor

Yendor
"During times of universal deceit, telling the truth becomes a revolutionary act."
                              George Orwell

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Mikey T.

  • 3545
Re: What About The ISS?
« Reply #117 on: June 30, 2015, 08:19:00 AM »
Well, I could look into RFID tags like that, but it needs to be initiated from the door opening, I wasn't thinking about having the base station constantly polling the access points for updates.  I will look into it a bit more.  I did some research on RFID readers for another project during my senior year of college.  I designed a wall avoidance system for a quadcopter and the construction engineering guys wanted to add an RFID reader payload to it to present it as a cost effective inspection platform for large buildings, specifically concrete structures and their RFID tags attached to strain gauges inside the concrete and rebar.

Since you can use them to transmit data from sensors, I guess I could try to have it change its ID based on the status of the door/window.   But that means the base station would be polling constantly.  Gonna reduce the lifetime of my zigbee.

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Yendor

  • 1676
Re: What About The ISS?
« Reply #118 on: June 30, 2015, 04:49:08 PM »
Well, I could look into RFID tags like that, but it needs to be initiated from the door opening, I wasn't thinking about having the base station constantly polling the access points for updates.  I will look into it a bit more.  I did some research on RFID readers for another project during my senior year of college.  I designed a wall avoidance system for a quadcopter and the construction engineering guys wanted to add an RFID reader payload to it to present it as a cost effective inspection platform for large buildings, specifically concrete structures and their RFID tags attached to strain gauges inside the concrete and rebar.

Since you can use them to transmit data from sensors, I guess I could try to have it change its ID based on the status of the door/window.   But that means the base station would be polling constantly.  Gonna reduce the lifetime of my zigbee.

Mikey T.

Can you use a magnet and a NC reed switch that would open the reed when the door opens allowing a line to be pulled up via a pull up resistor. Use a large enough value resistor so you aren't drawing too much current across it. This would generate an interrupt to the processor. Then the NO side of the reed switch would complete the circuit for the RFID device. Then the processor would poll all the RFID devices to see which one generated the interrupt and will communicate. I guess you would only need one wire for ground. Is this any help?

Yendor
"During times of universal deceit, telling the truth becomes a revolutionary act."
                              George Orwell

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Mikey T.

  • 3545
Re: What About The ISS?
« Reply #119 on: June 30, 2015, 06:17:44 PM »
True, but I still would like to get it to being two little pieces that you could attach to the door and doorframe to make it as easy as possible for a person to install for themselves.  I will look into some of the suggestions I have received here, and thank you all for your input.