All Mechanical- a flaw in thinking.
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Ever hear an incoming call on your computer speakers?
Really annoying in an office environment
And I have a Ham Radio that you can bet can be "heard" on most consumer amplifiers close by, and it ain't the Ham Radio that is at fault. I can monitor my transmissions with an "unplugged" clock radio.
Most of the simple mosfet circuits I've seen on this forum do not have input ESD or EMI protection components other than a pull down resistor.
This thread is fun
Hah - good point. But actually, this is basic radio TRX (transceiver) engineering, and something that had to be addressed on Day 1 that a radio transmitter-receiver was invented.
Problem: when the transmitter fires up, the receiver gets instantly fried because (a) it's right next door, (b) it's designed to amplify 10 milliwatts not 100 Watts, and (c) it's listening on exactly the same frequency (let's forget about multiplexing here OK radio techies )
Solution: kill the RX circuit a microsecond before the TX fires up, then enable it as soon as the TX shuts off. And this is still used today in all radio transceivers (like for example cellphones) as it's the only way they can work.
Yes - this is a common belief - but incorrect. The level of RF energy induced by a transmitter very close by is so high that the frequency is not relevant. Chips in a circuit are sometimes there to amplify 10 microvolts, and a cellphone parked next to the electronics in question can induce a voltage of thousands of times that. This is why so many things have been zapped by cellphones. The number of such incidents has decreased over time, though, as (a) cellphone transmitter output power has dropped by a factor of ten or more, and (b) manufacturers of other widgets have learned they need to protect their stuff against the ubiquitous personal radio transceiver parked next to it.
When they first came out, those big old analog cellphones were lethal, they zapped lots of stuff. But the newer digital ones with a comparatively tiny transmit power are a lot safer.
Hah - good point. But actually, this is basic radio TRX (transceiver) engineering, and something that had to be addressed on Day 1 that a radio transmitter-receiver was invented.
Problem: when the transmitter fires up, the receiver gets instantly fried because (a) it's right next door, (b) it's designed to amplify 10 milliwatts not 100 Watts, and (c) it's listening on exactly the same frequency (let's forget about multiplexing here OK radio techies
)Solution: kill the RX circuit a microsecond before the TX fires up, then enable it as soon as the TX shuts off. And this is still used today in all radio transceivers (like for example cellphones) as it's the only way they can work.
Yes - this is a common belief - but incorrect. The level of RF energy induced by a transmitter very close by is so high that the frequency is not relevant. Chips in a circuit are sometimes there to amplify 10 microvolts, and a cellphone parked next to the electronics in question can induce a voltage of thousands of times that. This is why so many things have been zapped by cellphones. The number of such incidents has decreased over time, though, as (a) cellphone transmitter output power has dropped by a factor of ten or more, and (b) manufacturers of other widgets have learned they need to protect their stuff against the ubiquitous personal radio transceiver parked next to it.
When they first came out, those big old analog cellphones were lethal, they zapped lots of stuff. But the newer digital ones with a comparatively tiny transmit power are a lot safer.
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Ever wonder how long (electrically) a typical ecig is and what would be the free space resonant frequency? Or how close do you think an ecig is to a 1/4 wave at some cell frequencies? What is the chance that an unshielded antenna attached to the center post of an electronic cigarette could develop enough RF voltage to be damaging?
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have you ever actually dismantled a cell phone and looked at the build quality
i'm j-std class 3 solder certified, and work on microwave components for major military contractors. there are very few consumer electronics that are built for durability, hence the reason people are a bit wary of electronic failures.
a properly designed, properly build electronic mod will outlast a purely mechanical piece of equipment time and time again. But therein lies the problem. MOST consumer electronics are not properly designed and built, especially from china. They are build well enough to work, but not well enough to last.
Sometimes, problems that are deemed electrical in nature are often mechanical at root cause. For instance, poor wiring leads to a wire bundle rubbing against a chassis during operation, causing a short. The mechanical design flaw caused an electrical problem.
Just last week I finished repairing a returned unit that was originally built in the early 70's. It did not have a single failure until a few months ago.
Since building my latest mod that integrates a capacitive touch switch, I have not had a single problem with my mod. Previously, I was replacing mechanical switches every few months.
That being said, it is far easier to design and build a reliable mechanical piece of equipment than it is to build a reliable, durable electrical equivalent. As a general rule though, the less moving parts a piece of equipment has, the better.
But perhaps I am somewhat biased, being an ET for a defense contractor, and an electrical engineering student
careful with the RF theory, you're going to end up sending me on a tangent
dammit now you have me thinking about performing an experiment at work, as I have access to RF amps that transmit anywhere from 1-16000 watts
RF burns, anyone?
Using a cell phone in a Prius would send you on a tangent
(I stuck at 1000 watts. Wonder what a plastic carto picks up?)
(I stuck at 1000 watts. Wonder what a plastic carto picks up?)
Using a cell phone in a Prius would send you on a tangent
lol it has the potential to, and could be quite entertaining
Yes. I plug mine into my laptop when the GPS is running and I get to see at least one extra satellite with the increased RX capability (if I hold the ecig up so it can see the horizon).
j/k
j/k
Yes. I plug mine into my laptop when the GPS is running and I get to see at least one extra satellite with the increased RX capability (if I hold the ecig up so it can see the horizon).
j/k
i see a new mod in the future: GPS enabled ecig. Never get lost while vaping again!
Holding it up, love it (saw the ps).
I have a particular device I use to keep a certain step son of mine from constantly texting at family dinner (about $40).
The first time, on a Sunday evening, he got up from the table (no signal) and walked around holding his cell phone up in the air. Over by the door, each window. Never caught on I could hardly hold a straight face. So yeah, hold em up high.
I have a particular device I use to keep a certain step son of mine from constantly texting at family dinner (about $40).
The first time, on a Sunday evening, he got up from the table (no signal
) and walked around holding his cell phone up in the air. Over by the door, each window. Never caught on I could hardly hold a straight face. So yeah, hold em up high.
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Holing it up, love it (saw the ps).
I have a particular device I use to keep a certain step son of mine from constantly texting at family dinner (about $40).
The first time, on a Sunday evening, he got up from the table (no signal
where, exactly, did you find this? Inquiring minds need to know
Cellphone jammers are anti-social. It is unfairly restricting the human rights of the teenager to be constantly connected to their peer group, leading to anxiety and possible psychosis. And hissy fits.
isn't it the role of the parent to be as uncool as possible? Not a parent yet, but if my child thinks I'm the coolest parent in the world, and regards me as his/her best friend, i would consider myself a failure.
To his/her peers your being uncool will be good. When it comes down to brass tacks (what is the etymology?) being regarded as a best friend is a success.
most kids I know that consider their parents their best friend are spoiled brats who are going nowhere in life, relying on mommy/daddy for everything. Hence my reasoning.
Agreed. I meant behind closed doors for the BIG issues. Didn't mean any offense.
By best friend -- I meant the concept best friend -- trustworthy above all etc.
I think it depends on the kid myself. If he\she is a problem child, then of course you are going to have to play more of the bad guy role. Or maybe a mixture of good guy bad guy. My old man was hard as hell on me, which I thank him for now. But at the same time, he was the last guy I would have gone to for a "real" problem, because I knew the trouble I was going to be looking at. I want my son (and soon to be daughter) to be able to tell me anything.
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