Personal Safety From Google

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yogi
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Re: Personal Safety From Google

Post by yogi »

The power supply sounds like a likely source of RFI. Any switching that creates square waves will generate harmonics. But it's hard to believe that the harmonics would be strong enough to measure all the way up at 433MHz. I have a 650 watt power supply in the tower and it has a fan as do most others. However, this PS is smart, so they say. The fan only turns on when sufficient current is being drawn to heat things up. Of all the times I looked at that fan, I've never seen it on. This design is geared toward quiet, which was a criteria when I built it. So, if the fan is PWM (pulse width modulated) then that cannot be the source of the RFI because, well, it's never running. However, I do have four other fans mounted in the cabinet also PWM. They never turn off, although I have the option to do so manually. In that case the RFI would always be generated.

Further use of the lightning detector revealed that the false readings and the interference signals only appear when there is lightning in the area. It's been calm for a couple days now with no interference signal, and no false lightning indicators. I must conclude it's the sensor that is malfunctioning and not my RFI filled room causing a problem. And, by the way, I only can attach three sensors to my AccuRite. The setup display tells me which device is assigned which channel.

In about two hours I'll be attending a wedding over the Zoom network. In my case it will be via an extension added to FireFox in conjunction with Google Canendar app. I have no idea how this is going to work but I did do the necessary setup. The kids use an app on their smartphones. If all else fails that's what I'll do. Stand by for future developments.
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Re: Personal Safety From Google

Post by Kellemora »

When I used to work on video games, the large coin operated type, after they came out with switching types we often had to put the power supply in the bottom of the cabinet and place a metal box over it. They played havoc with the games, hi hi. Not the newer games that came with switching power supplies, but the older games where we had to replace the power unit with switching type.

I had one computer eons ago, back when I was doing a lot of Ham work, that put out a very strong signal around 17 to 20 meters. There's basically nothing in a computer that should hit around that frequency that I know of. But boy this old computer really did and big time. I had to turn it off if I wanted to use 17 or 20 meters, but it didn't bother anything else. One would think if it messed up 20 it would also mess up 40 and 80 too, but nada, perfectly quiet up there.

I've never loaded zoom, don't really see why I would need it. At least not yet!
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yogi
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Re: Personal Safety From Google

Post by yogi »

Computers have a lot of potential for creating RFI. The greatest source would be them there square waves used for data and those supplies which get their power from switching (square waves). Why they might be tuned to a certain band is the mystery. It would be interesting to get a field strength meter and an rf spectrum analyzer to see exactly what is going on. But that interest could be very expensive so I probably will never know. :lol:

Zoom is simply a way to get a crowd all on the same video channel. It's done in "meeting" format. That means one person initiates the session and all the other attendees sign in using a phone number and password. This is what my daughter, the teacher, has been and will be doing this school year. She teaches 5th grade and all her students are well versed in how to use the app. She custom designed a front end (must be simple because she is not webmaster literate) for the students to log in and do the class work. It's a pretty darn spiffy way to run a school session and I think the only reason it's not more popular is the teachers being unwilling to learn something new. With this kind of technology available, I don't see a reason for kids physically being in a class.

As far as weddings go, the one I attended was run by amateurs. LOL The Zoom session attendees can gather ahead of the event. Thus all the relatives were there before the 4:00 PM ceremony. That part was kind of like the traditional weddings. When I tried to download the Zoom software the choices were overwhelming even for a geeky type as myself. I chose to do it all in a browser figuring that would be the most simple and least invasive way to do it. This method required setting up a Zoom Event in Google's Calendar app. There were no further instructions other than to be sure to have the Zoom extension installed.

Before the big ceremony I chatted with my daughters and they never heard of what I was doing. LOL They both have the app on their smartphones and my school teacher daughter had it on her laptop too. So they sent me the link to install it on the phone, but I didn't want to do it given I have no feel for the security risks. I know the session is not secured but the after effects is what I was concerned about.

About 15 minutes before show time I tried to get the FireFox session gong. Nada. Nothing was happening there no matter what I did. Wife was busy trying to install it on her iPhone but never succeeded. It seems Zoom requires Google Play app to work on an iPhone and Apple is very dissatisfied with anybody trying to use Google software on their equipment. The same guys who told me it could be done in a browser also say it can be done on OSX. Sure. Right.

As the appointed hour approached it looked like disaster was looming. So, I bit the bullet and installed Zoom on my clever phone. No problem. No set up required or anything. Download it and we were into the session as quickly as I could enter the number and password. Google sure has it's act together with this app in spite of the fact it is not Android based to begin with. There had to be about two dozen windows. Each one had a live view of the guests attending this event. We browsed through them all and waved back and forth at the people we knew, but there was no audio. Seems like you must pay Zoom if you want to hear anything. It was 5-10 minutes into the ceremony when we began to wonder when the show will start. Apparently it started on time in some other window. There was no notification or announcement that the event began. We were expected to know that and know how to find it among all those sub screens. Well, we did find it by luck. We missed the first ten minutes but got the full last ten minutes. Then the person with the camera who started all this closed the session. That was the end of that.

What we saw was beautiful. It was an outdoor wedding in some garden in some resort in Illinois. Truthfully it was anticlimatic. The ceremony must have been awesome, but we missed half of it. Apparently no video of the full proceedings is available. I suppose it was nicer than not being there at all, but something more was needed to make this event a celebration of the caliber it deserves. As far as Zoom the software goes, it's way too flexible. It's optimized for smartphones and works really well. If you want to go beyond what you get with the free air time, it will cost you $16/month. It might be worth it if you enjoy video calls to people you know, or if you participate in staff meetings while not being in the office. I think this is a fantastic way to do remote meetings. Doing weddings this way needs something in addition to the default package.
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Re: Personal Safety From Google

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Based on everything you said above, it really sounds like something I don't want at all.
The first is, you have to use a phone number, which probably means a cell phone number not a landline number.
Let me know how much spam you end up getting from giving out your phone number.
Then you ended with, if you want audio you have to pay 16 bucks a month.

So my question here is, why not just use IRC actually ViRC2 for video and audio? Maybe it's not around anymore? Maybe it doesn't work with groups? I used IRC to chat with Debi back when we were long-distance dating, hi hi.

Sorry you missed half of the wedding because of all the screens they put up!
But glad you had the opportunity to be there virtually!.
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yogi
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Re: Personal Safety From Google

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The phone number isn't a problem. I'm not sure how that is generated, but it's a number specific to the Zoom app. I know that Skype and Google do the same thing. They give you a phone number that they invent and can only be used on their network. That number acts as a unique identification on the network and I don't think you can use it outside the app.

Zoom provides its service free for one on one contacts. When you do group meetings they limit the free time to 45 minutes, or something like that. And, to be perfectly honest, I don't know how the audio works. I only know we did not hear anything and there was a button to enable it, but I didn't have time to try and figure out what was needed. The fee I mentioned is real and will give you everything they got for a month.

Nobody but you and three guys in Siberia know what "IRC actually ViRC2" is. LOL That's even older than ancient and before technology was invented. Zoom is pure 21st century and designed for the millennial mindset. It's really not much different than those virtual doctor's office visits. The medical practice is paying the fee if there is any. Most do because you get the security that way, but some, I understand, use anything you have access to regardless of it's security level. It's for that reason I opted out of the virtual visit a couple weeks ago.
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Re: Personal Safety From Google

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Both of my doctors do virtual visits and probably get paid the same as for a real visit, hi hi.

My GP doctor I only have to go to their website and click that I'm on in the box for virtual appointment.
I do have to plug in a microphone to do that, and make sure my mike is turned on ahead of time.
The box that pops up warns that my mike is not connected or not turned on, hi hi.
But I don't have a video feed of me due to no camera, but I see the doc in the box, usually the nurse first.
Besides talking, I can also type back and usually have things ready to cut n paste, like my Blood Pressure, Temp, O2 level, and the list of Blood Glucose readings since the last visit which is actually sent via e-mail later, only last nights blood glucose is sent on the cut n paste I do, which she copies to my chart as we speak.

My Specialist heart doctor I can also do on-line, but it is entirely different in how they do it.
It is more like a form I fill out, but I have to do everything on the form a day ahead of time.
I have a copy of the form, so on my exercise day, I check everything while I'm doing each exercise.
The only thing is, I need oxygen when I exercise now, so I have to start exercising without the O2 and use a timer, when my O2 drops to 89, he wants to know my heart rate, length of time it took to drop, and of course my starting heart rate and O2 level. Once I drop down to 89 then I'm supposed to go back on O2 and complete that exercise without actually stopping, which makes it take much longer for my O2 to get back up again, and it makes me more tired than usual too.
In order to fill out the form on-line it takes me to another secure and encrypted website where I enter the data. Then when I finish that, it pops me back to the first website where I have to wait for a comment from nurse or doctor.
But all I get is a checkbox that asks if I received and read the comment. The second I click the checkbox it goes away and I'm logged out. I also send my heart doctor a copy of my readings I give to the my GP doc. Not the whole thing, just from the last time I gave him a copy. I also always bring all of my doctors a paper printout from the last time I was on a real visit.

All that typing and I've only done three with my GP and two with my Heart Doc.
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yogi
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Re: Personal Safety From Google

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I too have wondered if the doctor gets paid the same for both in person and virtual visits. Medicare sends me e-mails all the time and lately they say they fully support, and encourage, virtual office visits. I've not read beyond that to see if the fee is the same. Regardless the fee is covered.

You do a lot of the vital statistics measuring on your own time. I don't think that part is much different. Even though I do a walk-in visit with my doctor there are several forms I must complete on line. It's all stuff the nurse used to do ahead of the doctor's visit. I don't mind doing it this way because it saves time when I'm in the office. The less time I spend there the better I feel. A normal visit typically includes the doctor listening to what's going on in my chest. I guess they simply forego that part when it's virtual. Same for temperature and blood pressure. However, I can do my own BP measurements because I have the machine. Now that I think about it, I should test it out to see if it still works. I've not used it in many months. My last visit to the doctor's office had a BP reading that was excellent. Much better than it's been in years. I guess those pills I'm taking are doing something.

I see something like a telephone booth in every Walgreens in the not too distant future. You will step inside and the door will close and you will hear a faint humming sound. Some bluish light will glow around you and then a sweet sounding voice will announce you are healthy. That will be it for check ups in the future. If you are not healthy the floor drops out and you are immediately transported to the nearest ER where the robot on duty decides if they need to call the coroner or not. LOL
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Re: Personal Safety From Google

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My good BP machine finally gave up the ghost so I bought a new one that was junk.
Went back and got another good one, but none of them are as good as they used to be.
My new one works on my upper arm so is fairly accurate, but still cheaply made.

I have to keep a daily running list of my glucose levels anyhow, so I just go ahead and add the other vitals along with it.
Doing that and turning it in, lets the doc see how I'm declining. It also lets him order a test to see about my getting things like being put on oxygen overnight, after an overnight reading test. And now portable oxygen tanks since exertion, even walking pulls by O2 way down. I'm sure it won't be long before I'm on O2 24/7.

I had a doctor once who used some type of blue light on my hands. Whatever it was or did, it seemed to help slow down my arthritis in my finger joints. It didn't hurt or feel hot or anything, but it did cause a slight buzz feeling, but not exactly a tingle feeling. I mentioned it to my doctor down here, and he said it was a fad that never proved successful to move on beyond the cities it was experimented in. Besides they can do the same thing using ultra-sound devices.
I don't believe him of course!
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yogi
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Re: Personal Safety From Google

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Heat is known to help arthritic joints. Blue light, however, is at the opposite end of the spectrum where the infra red heat frequencies reside. I guess when you go to one of those tanning salons you lay under a blue light so that the UV must have some effect on the skin. As far as penetrating down to the joints, well, it seems unlikely. However, if it made you feel better, who cares what the theory is? Doctors were at one time dead set against alternative medicine. It was not even legal for them to discuss it. That has changed now and some places will even recommend unproven treatments be pursued on your own, relieving them of any responsibilities of course. Doctors are just as biased as us street folks and they have preferences for the way they treat people. Thus, even if the blue light worked for you, it might not have been part of the normal regimen for your regular doctor.

The BP machine I have was ordered online and I am certain it was slightly more than $100. I thought it was the best of all the ones I've seen and used previously but didn't think it was of professional quality. Then, one day while accompanying my wife to her doctor, they used the identical machine to measure her BP. My own doctor's assistant used something similar. So, they might be made of plastic and look cheap, but at least some doctors think they are good enough. I have seen the professional equipment in the catalog of a place I deal with in New York. It's hospital grade stuff all around. I believe one of those automated BP machines was going for nearly $700. It certainly was well made and would last longer than my heart, but I don't think it is worth the price for what I do.
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Re: Personal Safety From Google

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The blue light I talked about was not like the blue in the tanning beds I've seen. It was almost like a dark purplish blue, and it flashed on and off faster than we could detect with our eyes. No heat per se, but it did make your hands buzz. However it worked it did keep my hands from getting so bad and may have halted the progression as well. I do wish my thumbs joints were hit more though, as it is my upper thumb joint that hurts the most now. And no doctor down here even knows what that doc may have used on me.

Many years ago, for my late wife, I bought a recording on paper discs, a used Pulse Oximeter, and it was hospital grade. Her doctor loved to see those discs when she came in. This, plus some tests he did is how she managed to get liquid oxygen.
Also, from Walgreens, I bought their old blood pressure station, not the whole chair and mounting table for it. Just the unit itself which came with the L-shaped arm board you slipped your whole arm into. They were nice enough to add a new cuff and hose to it right before they sold it to me for only 250 bucks. It was perfectly accurate up until the day it died with a loud pop, hi hi. But by then we also had a small one like we have today.

And you can laugh at this. When they were rebuilding the ER at St. John's Hospital, I managed to buy a Post-Glover Line Isolation Transformer. They were mounted in the wall in the old ER rooms. Big heavy sucker! I built a wooden box to house it in, on rollers, for use in my Ham Shack. Ironically, I only paid like 100 bucks for it, and of all the things that sold at my auction for super cheap, the auctioneer managed to get like 280 bucks for it, along with some other loose medical equipment I still had laying around. Like a tall O2 tank, still full, I had as backup, and two regulators. I kept one regulator that fit the smaller size tanks, and I'm actually using it in my office on that O2 tank.

I did bid on one of those big lights they have ceiling mounted over operating tables, but I was outbid by a long way on all of them. I didn't want it for my house, I wanted it for workshop. But in a way I'm glad I didn't get it. I probably never would have had it put up after I bought these super power groove 8 foot long 4 light fluorescent fixtures for next to nothing. Now those I put up right away!
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Re: Personal Safety From Google

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I know of lights that are predominantly ultra violet. That's the kind they likely use in tanning salons. There is also what I have heard called black light which seems like a deeper shade of blue than the UV light. I've not heard about either of them causing a buzz in the hands. LOL It's too bad you didn't find out exactly what that light was all about. No doubt you could have duplicated it because you seem to have a lot of interesting resources. You dealt with auctions a lot and I suspect there are many interesting things to be acquired that way, more so than what you could find at a flea market. I am not laughing about the purchase of a $100 hospital grade isolation transformer, but I am scratching my head wondering why you would need such a thing.

Those surgical lamps are amazing. It would be wonderful to have one over my workbench. Then again, there isn't much to do around here so that the bench and light would not get used very much. I still would like one.
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Re: Personal Safety From Google

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The Line Isolation Transformer was for my Ham Radio Shack. When you have over a dozen different electronic devices all in metal cases, and some of them made before polarized plugs, you can get a nasty shock.
FWIW: Every pinball machine, video game, Juke box, and casino game has a line isolation transformer in each one. Basically any machine, including most restaurant machines. It is a safety feature.
Now I'll admit the HUGE hospital grade was gross overkill, I probably used less than 10% of its capacity at any time.
But on the bright side, when my tower took that lightning hit that knocked it down, I lost no electronics in my Ham Shack, even though sparks flew all around the room from a rotor cable.
Can't say the same for the clock radios in the bedroom or the TV in the den.
But the strike there was nothing in comparison to the hit we took here a few years ago that killed nearly everything.

They do look and work neat!
I'm wondering if I should have any concerns over these LED lights?
I replaced the four lamps in the ceiling fan in our bedroom. I bought those fancy Edison looking lamps, which are dimable and were only supposed to be 40 watt equivalent. What I liked about them is they looked like a real lamp bulb, no big transformer box with it. The power is reduced through a tiny circuit board about the size of a penny in the bottom of the lamp.
However, they are putting out light equivalent to 75 to 100 watt bulbs, not equivalent to 40 watt bulbs. We have to be careful not to turn the lights up too bright else they will blind you, hi hi.
But my concern is not about the brightness, but about the high frequency emissions LEDs produce.
Most of them turn on and off at a high frequency much greater than the 60 cycles per second we are used to.
An incandescent bulb you will not notice the 60 cycle flicker because they don't cool down fast enough.
But an LED powered by a voltage reducing transformer will flash at 60 cycles, which is very noticable.
I suppose this is why they use switching power supplies and high frequencies to run them.

I read this not too long ago:
The AMA says that life-long exposure of the retina and lens to blue peaks from LEDs can increase the risk of cataract and age-related macular degeneration. Studies also reveal that light emitted by LEDs can cause retinal changes, if there is high exposure for even a short period of time.
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Re: Personal Safety From Google

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I know the theory that makes isolation transformers safe from death by touching a ground wire. LOL It's just a regular transformer that is not connected to ground in any way. Safety is a primary concern for hospitals. I'm guessing you were very lucky not to blow up your radio station when the rest of the house was hit by lightning. I don't understand why that worked so well because any high voltage on the primary side of the transformer would get transferred over to the secondary by design. Most of the isolation transformers I've heard about are wound at a 1:1 ratio so that if you have a million volts input you will see a million volts output. The only difference is that the output side is not tied to earth ground. Which brings up a paradox of sorts. It's been a dozen years since I've seen the inside of a hospital room, but back then all the equipment had a third wire for grounding. Seems like that would defeat the purpose of isolation. But then I am easily confused.

Also, I figured LED's were DC devices. At least that is what my past experience has been in the radiotelephone industry. I suppose those that you put into your living room lamp have an a/c to d/c converter in their base, but how that gets translated to flickering LED's escapes my understanding. I'm also certain light can affect retinal function. To be honest I don't recall reading any warnings about it. I don't watch television so that I'm safe in that regard, and my PC monitor is made of LCD's. I don't know of any ill effects I might have suffered dealing with all these things in my professional life, but I suppose it's possible.
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Re: Personal Safety From Google

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Oh no Yogi - A line isolation transformer is insulated between the input winding and output winding.
Also - The isolation transformers significantly block the voltage spikes, switching transients and noise that originate in the supply side from being getting transferred to the load side.
If the coils are large enough, they can also balance out a rapidly fluctuating input voltage to smoothen out the ripples.

Actually, hmm, how do I explain this one. OK, firstly, yes LEDs are DC devices, but not really.
The D in LED stands for DIODE. Now what does a Diode Do? It allows electric to flow in only one direction.
A Diode is used on an AC circuit to produce a pulsating DC output.
Adding a Diode to each leg of the AC circuit produces two pulses opposite each other, which is how you get a square wave DC output.
A Diode Bridge is used to help smooth out the pulses, and then inductors are used to smoothen it up even more. Add some capacitors and you can get a smooth output.

Actually, the new way of making Lighting Fixtures using LEDs is to use a high frequency AC fed to the LED device. At high frequencies the flash is way to fast to ever be seen by the naked eye.
That being said, most of the transformer driven LEDs are using a reduced DC voltage to the LED to produce light.
Most use a switching power supply which does generate RFI, while the newer AC method does not do that so much.
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Re: Personal Safety From Google

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Something is being lost in the translation here. LOL

All transformers, regardless of their practical application, isolate the primary winding from the secondary winding. The energy in the primary gets transferred to the secondary via electromagnetic radiation, known as inductance. If the primary were connected to the secondary winding that dead short would kill the electromagnetic radiation and the AC would pass as if it were a simple coil of wire. Actually there still would be inductance due to the physical winding of the wires, but the transformer effect would be short circuited. The thing that makes an isolation transformer what it is has to do with the fact that the primary coil is generally connected to ground, or as you would know it the common wire. Thus if a human were standing on the ground and touched the input that human would become the common wire. The secondary winding of an isolation transformer has no such common wire. The ends of the coil float. There is no common conductor. Thus death by electrical shock is prevented.

As far as noise reduction and load management goes, that's a gray area for me. I don't know enough about the theory of transformers to understand how an isolation transformer on it's own can accomplish such things.

All I can add to the comments about LED's is is that they emit light while conducting. And, yes, they conduct in one direction only. I'm fairly certain the high frequency power supplies are used because physically smaller components can be used in the source when the frequencies are high. Smaller in this case translates to cheaper.
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Re: Personal Safety From Google

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Well, all I can say is they do suppress noise, voltage spikes, surge protection, and a whole list of things a normal step-down (or up) transformer does not do.
There is a LOT of noise on an AC power line, and next to none after going through a line isolation transformer.

Here is an example that might make sense:
Most of us Hams provide several turns of our coax outside of our house to bust static and repel voltage spikes during inclement weather conditions. I had a metal plate to ground with coaxial connectors on the outside of my wall, so no coax came directly into the house. On top of that, inside the house I had Gas Lightning protector bottles also grounded to earth ground.
The only thing I forgot to protect was the ribbon cable from the rotor to my controller box. Which is how the lightning got in and threw sparks all over my office and ham shack. That ribbon cable was fused to the back of my metal file cabinets.

Although LEDs are Diodes, they don't work very well when used in place of a diode in a circuit. Learned that the hard way. I was trying to be cute by using LEDs in place of diodes, figuring this way I could tell if one went bad, hi hi.

I did wire 25 five-volt LEDs in series, and plugged them straight into an electrical outlet. They ran for about 4 years before one burned out. I did figure out which one burned out and replaced it, but only ran another few months before it went dead again. After that I tossed it.
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Re: Personal Safety From Google

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As often happens, I think we are saying the same thing but in different languages. LOL My explanation of an isolation transformer was simple but in the real world it gets more complicated. That isolation of the primary from the secondary winding of the transformer is taken to extremes. Normally you would just have lacquer coated wires wrapped around a core to do the transformation. Isolation transformers go through a much greater extent of insulation and separation. I am guessing it's that additional insulation and a few other things that does the line conditioning. A transformer by itself is limited in what it can cancel as far as noise goes.

The coil of coax outside the shack is essentially a tuned circuit that filters out noise. The coax itself has a capacitor value and the coiled wire tunes it to a certain band. There is a vague, very vague, memory of such things buried in my brain. I don't think I did it myself but I'm pretty sure some of my buddies did. I suppose an isolation transformer can act the same way. Some day I might look into it in more detail. I make use of the opposite principle when using a long extension cord to run my garden equipment. I go through some trouble to be certain the 50 foot length of cord is not coiled anywhere. Coiling it can cause it to act like an autotransformer and in theory create equipment damaging line voltages.
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Re: Personal Safety From Google

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I was just thinking back to our Dynamo at the greenhouses. It was a massive generator to power our boilers and a few other things when the power was out. The oil to the boilers also had to be heated. And I remember this big iron coil that sat on one side of an asbestos panel, and another coil on the other side of the asbestos panel that went to the oil heaters.
The reason I remembered it was because I was amazed back then that it had no wires going to the one on the heater side, other than the two wires that went to the heating element connections.
Back then I thought, where is it getting the electric from? It was on a big concrete slab inside the oil heater room.
The night fireman told me the power comes through the wall. At the time I thought he was pulling my leg.
But then later as I studied electric and got my ham radio license, I figured out what was going on.

Today, you can have devices you just lay on the charger, and they work basically the same way. The base has a transformer that is powered, and the device has a transformer to pick up the magnetic cycles from the first transformer.

Yes, a coil in your extension cord could cause a problem if there were another coil laying across those wires to your device.
I had a retractable light with the coil hanging up on the ceiling. Rather than make it retract, I would just coil the wire and hang it on a hook on the side of my workbench. Big Mistake that was. Not when it was on, but when I turned off the power to the garage, if the pull down light was on, it would instantly burn out. So I figured, turning off the power caused built up voltage in the line to like double or triple and burn out that light. I solved that by turning off the pull down light first, then turn off the garage lights and outlets. I still think that may be what caused my switch in the lamp to go bad a couple of times too.

Mom had a pull down light over the kitchen table I had to fix for her many times too. But mostly it was because the double winding mechanism would break, often the pins that held the pulleys in place would wear out super fast. I eventually replaced those cheap pins with hardened steel pins and that part never broke again. About once every three or four years I had to replace the wires to appease mom. If she saw a frayed spot on that braided linen cover on the wires, she had me replace it. The last time I replaced it, I did so using the cord for an Iron. It cost nearly double per foot of wire, but that sucker never wore out after that, hi hi. I also replaced the plastic grommets the wire passed through with Nylon grommets, so they never broke or came out anymore either.

Wow, so many years have come and gone since then. It almost hurts looking back that many years from where I'm at now, hi hi.
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yogi
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Re: Personal Safety From Google

Post by yogi »

Funny that you should mention it, but my smart phone charges every day without attaching any cables to it. There is a wireless charger on my desk that is a flat white plastic oval on a stand so that when you lean the phone against it the phone is upright. This allows the phone to be used while charging. I don't know what the heck Google did but I can go from about a 25% charge to full charge in roughly a half hour. This is the ultimate application for an isolation transformer. LOL

Back about the time you were trying to figure out greenhouse dynamos, I lived in a house that was heated by a oil burning stove. I don't know why this stove worked as well as it did but it kept four rooms toasty warm in the winter; that is, if the fuel oil did not freeze. There was a 250 gallon tank outside my bedroom window and it was filled with fuel oil. A copper tube ran from the tank through the outer wall of the house, through my bedroom, and onto the stove. That baby worked well most of the time. However, when the temperatures got close to zero or below, which was rare in those days, paraffin would form in the fuel line and stop the flow of oil. We were all shocked that fuel oil does that, but the vendor told us it was normal for the grade of oil we were buying. If we paid more for a higher grade it would be good down to a lower temperature. I don't recall clearly how dad got that fuel line going again, but I'm thinking he used a propane torch to heat the line and get the oil flowing again. Sounds insane, but my dad is the one who had that crazy brother (my uncle) I talk about once in a while. :grin:

I had one of those coiled drop down lights in my garage. I saw the mechanics at the gas station using one when they repaired automobiles and figured it was a good deal. I used that lamp for many years without it causing a problem. In fact I still have it in my basement here, but never found a reason to use it.
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Kellemora
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Re: Personal Safety From Google

Post by Kellemora »

A normal transformer usually has an iron core, and a coil is placed on each leg.
An isolation transformer usually has the two coils separated from each other.
Just like your no-plug-in chargers!

Our cut flower shop was heated from oil to a furnace, the tank was outside. However, the lower half of the tank was insulated, and there was heat tape wrapped around the tubing that led into the building. We didn't have to worry about turning it on, because some type of bi-metal strip triggered the relay to send power to the heat tape below like 10 degrees I think it was, at least it had a 10 on the little metal box anyhow.
At my his dad's house and at his house, the oil tanks were down in the basement in the furnace room.
In grandpa's house, the oil furnace was in what was the coal bin at one time.
I remember the old coal furnace looked darn near like an octopus, hi hi.
Ironically, grandpa taught me how to bank a furnace, actually both grandpa's did.
That was something we didn't have to do in the coal boilers because they were manned 24/7 during the heating season.
I hated having to work in the boiler room, but it was required all of us kids learned that too, hi hi.

I had two small drop down lights, and the one big gas station style type. The newest of the small drop down light I had bought probably from Western Auto, and it used a flat ribbon cable, which I thought was neat at first, because it was a much longer cable. But then the problems of a ribbon cable reared their ugly head. They twist and kink real easily.

My brothers truck that he used to move pinball machines, video games, and vending equipment, had four winches mounted on a framing piece. Two at the top on each edge, and two on the middle stringer just in from each edge.
All four used flat straps. We also had this special dolly designed to lift and move pinball machines. The guy who thought that thing up needs to get a medal. At least the one we had anyhow, had every feature you could want on one.
It had fairly large wheels so you didn't have a problem getting over thresholds or bumps.
You simply slid it under the pinball machine from the front. Laid the pinball head down over a tarp on the glass. Tapped on a foot pedal to lift the machine so the legs were about 4 inches above the floor. Rolled it out to the truck, took the four legs off the machine, then stepped on another pedal that would raise roller bars to lift the machine a tad higher so you could roll it off the dolly and onto the truck, which also had roller bars on the floor. If not then we had two small corner dolly's we would set under the front corner of each machine to roll it onto a truck. The lift itself would raise up to the height of pickup trucks, vans, even box vans but now quite as high a tractor trailer trailer.
I've seen others that were only a lift, no where near as great as ours was, and sadly they cost more than we paid for our fancy one.
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