Comments by "Scott Franco" (@scottfranco1962) on "Technology Connections" channel.

  1. Note: a big advantage of solid state/semiconductor relays is that they can switch an AC voltage at its zero point. That is, it can watch the line voltage reach zero in the cycle, and switch at the zero point, effectively breaking the circuit when there is no current whatsoever flowing.
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  2. The basic reason why heat pumps are more efficient is simple: it is easier (less energy) to MOVE heat than to MAKE heat. Also, the freezing problem has a simple answer. Place the outside coils underground where it does not freeze. This works everywhere from Arizona to the arctic, and has the added advantage that the outside unit needs no fan and makes no noise. Alas, this obvious solution while used, is not that popular because many local governments suffer from severe head-stuck-in-posterior disease and don't generally permit such installations because they don't want to encourage deep digging (you might hit something).
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  3.  @jacksons1010  " I was expecting Tesla to use open standards." when the other standards are inferior, you don't have to. Also, Tesla standards ARE open. Tesla shares the design.
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  4.  @jacksons1010  Why? Tesla has offered to give the technology free to other makers, and to share their charger network if the other makers will help pay for it. What more were you expecting?
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  5.  @jfbeam  Yea, semiconductors tend to fuse closed, unlike most circuit boards, which tend to fuse open, or, as you say, contacts, which tend to fuse closed. When I worked in ICs we had a failure analysis presentation that showed why, complete with photos. Silicon... well, it melts with enough current. It forms a nice runny, and very conductive, river of molten silicon for an instant. I imagine that is right before it forms a miniature explosion. You kids won't remember, but we used to have UV erasable EPROMs with little windows in them. If you plugged them in backwards, cause, you know, stupid, or on purpose, you got a nice little light show. This probably accounted for the fact that bad ones never got kept around. They were too much fun to plug in backwards.
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  6. The Canadians have power coming to each carport, because if you don't plug your car in up there, it's dead in the morning. The power is for the car heater. So obviously it can be done if people want to/need to.
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  7. "boiling point of water is arbitrary in Celsius"... Yes, it is. Its 64 in hex.
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  8. You didn't cover the principle problem with deploying GFCIs everywhere, like the main panel. Many motors trip them. The problem is the motor windings can absorb enough current to look like an imbalance for long enough to trip the GFCI.
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  9.  @TheBackyardChemist  Do tell. I know it changes the waveform around, but it still has a zero crossing?
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  10. Because it is a looser. Elon said it best, your car is not plugged in at home when you need the battery power, and anyways you would be taking charge from the car that you need to drive it. Better to have a dedicated battery for your house.
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  11. I have had a Tesla since 2018, and a Bolt since 2017. I have two chargers, one Tesla at 48 amps and one J1772 at 30 amps. They are on individual drops from the panel, so they can both be used at the same time. I rarely use the Tesla charger now, because I get a charge for free at work, so why not. I could do a bunch of calculation to get the best range, or I could do what I do, which is just drive fast and don't worry about it. There are Tesla chargers everywhere in California, so its rare I need to extend range. 275 Kw chargers are common here, and non-Tesla chargers are here at 350 Kw, yes, more than Tesla. You can get a charge in 15 minutes, but frankly I rarely do that. Even just stopping for coffee more than covers 20-30 minutes. Even at my wasteful use of power, it cost $20 for the trip I just made from San Francisco to LA. Try that with a gas car. The point is, charge fast, drive fast, be happy. EVs at WORST are far better than gas cars at their BEST. And everyone is going to be driving that way in their EVs very soon anyways.
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  12. Ground and neutral SHOULD NOT BE CONFUSED. Like ever. As in never.
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  13.  @giacintoboccia9386  Which is why many people confuse ground and neutral ("hey, they go to the same place right?"). Ground and neutral are connected at the main panel, but NOT subpanels. To discuss why ground and neutral are NOT the same would take a whole 'nuther video (hey there is a video suggestion for technology connections). The short answer is that neutral is the center tap of the transformer on the pole next to your house, and ground is, well, ground! As in there is a wire that attaches to a copper rod driven into the ground, or your cold water pipe if that goes underground for an appreciable length (in most modern houses it in fact does not anymore). Can you get shocked by a neutral? Why yes you can. In fact, getting shocked by a neutral is one way (the hard way) to find out that, surprise! Ground and neutral are not in fact the same thing.
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  14. So how do off-the-shelf LED lights work? I assumed that they are RGB combined LEDs, but you are saying that would look unnatural. So how do bright white consumer LED bulbs work?
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  15. I had a 100 amp panel with an outside breakered feed. I added another 100 amp subpanel, thus 200 amps total. Most homes can do this. So no issue.
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  16. The Ampex spiral recording method was one of the pure feats of genius in the postwar era. Bing crosby heard about it and invested huge amounts of his personal fortune in the technology, resulting in his becoming very wealthy.
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  17. Please go read a book before you answer next time.
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  18. Dude this is turning into your obsession. Relax, its over.
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  19. Sort of. You could have a simple plunger arm do the job if they could STANDARDIZE the placement of the port, or even better yet, come up from the ground and drive over it.
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  20. You realize that a generation growing up with only LCD screens is going to consider this to be an irrelevant artifact of history.
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  21. As another video went into, the air does not just come through the walls. Most or all homes are built with an expansion gap between the sheet rock on the walls and the framing/joists. It is there to prevent the sheetrock from cracking due to expansion. Those gaps add up - you probably have more than a square foot of total space that comes from the outside. But outside.... where? exactly? There is the rub. Most commonly the outside is the attic, and the pathway into the house is through the walls and into the rooms via the various electrical and other outlets. In fact on some houses you can even see a trail of dirt next to an outlet from years of such "negative pressure" ventilation. You are drawing air that is dirty and dust filled from your attic into the house.
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  22. I used GE circle lamps long before CFLs came around. The real problem is that the lamps were hard to find when they (inevitably) went bad. Plus we had lots of 4' fixtures built into the ceilings at my house. Now that is all LED, including the 8' lamps in the garage. Kindof a shame, since the new high frequency ballasts were way betterer, but now I have like 6 8' lamps in the garage and they are dead quiet, vs the buzzing noises of the old lamps.
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  23. Credit where credit is due. Edwin Armstrong invented the superhet, and David Sarnoff of RCA stole it. This is the same guy who shafted Farnsworth out of the invention of television. Armstrong later committed suicide over this.
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  24. Could also be read as "what are contractors... you'll find out shortly" :-)
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  25. I used one of these "nano fridges" on a consulting job where I only had a desk and very little space. The company was paying for the power, so ya know, didn't care. Kept my diet coffee creamer in it.
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  26. Dude, give up..... Phosphors are pixels.
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  27. Yea, its amazing how much LCDs simplified everything. Now we are getting to the point were everything is going to be a color LCD with touch whether it is needed or not simply because of economies of scale.
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  28. Color fully bit programmable LCDs are taking over the world. Using other types of displays were just to save a few pennies. As volume discounting has more and more effect, even using black and white programmable LCDs won't give you a price advantage. Why do I care? Because I have to program these things. When some idiot designer tells me they are saving 5 cents by picking a cheaper display, despite the fact that we have to spend more time programming around the quirks of a special display, I get annoyed.
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  29. "directional changy bit" I don't know... these talks are too technical for me...
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  30. The increased use of extenders and plug strips came about largely because of the explosion in the quantity of small electronic devices, which tend to be low current devices. Thus having extenders plugged into extenders and full plug strips is not dangerous. All the plug strips I buy are equipped with breakers, and I buy long extender cords with reasonable gauges. Should the USA adopt better standards? Yea, but then we should be metric as well. Americans have never been impressed by arguments that we should join the rest of the world.
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  31. I had that same walkman cassette tape player. It was built like a watch and barely bigger than the tapes it played. I used to show people by putting it into a cassette box. It finally died. I was very sad.
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  32. Sarnoff's main talent was taking credit for other people's work, stealing others inventions (like Farnsworth), and inventing imaginary accomplishments (like claiming he heard the Titanic sinking on radio). Do some digging, the history is all there.
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  33. Led on a stick......mmmmmmmm.
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  34. I remember mp3 cd players. I bought one. It was interesting for about... 5 minutes. Putting mp3 on a mini hard disk make it look like a toy format.
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  35. You're going to cross 1 million!
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  36. And I though you were going to demo it with a suicide cord in hand standing in a bathtub with water in it.
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  37. Just get a file and file down that bigger pin and "voila".... you can plug it in either way! Also works if you take a big pair of cutters and cut off the ground lug.
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  38. I think if TC man here made a video about dishwashers that you light on fire, that would have covered the subject matter for this year...
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  39. The last time I developed film I used highly advanced Walgreen technology. Geez, no wonder we dropped film tech like a hot rock.
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  40. Exabyte was founded to record digital data on videotape for backup in 1985. They went fairly rapidly to 8mm video cartridges, as opposed to full size VHS, in 1987 (dates according to Wikipedia). The 8mm format had been introduced in 1984. DAT tapes were a similar if slightly smaller format, and indeed Exabyte bought my company, R-Byte, which made a DAT tape drive, in 1992. None of that occurred in a vacuum. QIC tape drives were introduced by 3m in 1972 (again Wikipedia), and although they didn't store Exabyte level densities, they were from 20mb to 400mb in later versions. So video tape as data storage had a competitor. Tape storage, going back into the open reel computer days, was generally used as computer backup on bigger machines and didn't come to PCs until the QIC days. Writable CDs were supposed to take over as a backup medium, but what actually happened is disc drives became so cheap for unit of storage that it made more sense to just purchase more drives and use them as backup, hence NAS or network attached storage and data vaults. Now, companies are just as likely to ship backup data to cloud companies.
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  41. So they divorced color temperature from brightness.... that's a good thing. What you want is a color adjustable bulb.
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  42. The people who like these are the same ones who claim you can make the room cooler by turning off the lights. Enough said.
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  43. You are becoming a new version of "the secret life of machines".
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  44. Meh The signal for turning in the USA driving slow(er) and hugging the side of the lane whose direction you are going to turn.
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  45. Ooooohhhhh, thanks. I haven't seen Triclor for years, they outlawed it in California. Now I know where to find it. I used to be able to buy it by the gallon can in electronics store. Great electronics cleaner.
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  46. I agree with most of what you said, but in our area, and probably most areas of the USA, the temperature, even on 90 degree days, drops into the 60s. It makes no sense to run air conditioning when the outside is that cold. You get the same effect, including storing cold air in the house, simply by drawing the cold air outside into the house. For that I have a "whole house fan" that actually goes one better. It both draws cold air into the house at night, and expels hot air from the attic at the same time. The result is that the house is considerably cooler by morning, and then you shut the windows to keep it that way. In this way, I usually manage to keep the house in the 70s until about 3pm even on 90 degree days. But then I turn the A/C on.
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  47. Electric water heaters are the least efficient, followed by gas water heaters, then on demand heaters. Good luck finding an electric on demand heater of any size. The vast majority of them are small under sink units. The most efficient are heat pump water heaters, but then you are back to storing the energy in a big tank. The least cost heaters are solar, but not that much better, because you have to pay to operate the circulation pump. The energy storage capability of a tank of water is impressive. I worked in a building that had air conditioning from this principle in The San Fernando valley outside of LA. It gets over 100 degrees F every day all summer. The air conditioning worked by storing water in the basement, and sending it to a roof array every night to radiate off the heat in the water to the sky. Then the water was used to cool the building by day.
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  48. If you rode that, and didn't realize that you were in an elevator, might I suggest becoming a lawyer or a politician, some job where critical thinking is not needed.
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  49. The "apartment dwellers cannot charge" thing is a canard. Most apartments have assigned spots, and I have never lived in an apartment building that didn't have covered parking and a light above it, meaning that it has electrical runs to the space. In Canada and other cold weather places, you have to have a plug at each space for the simple reason that if you don't plug you car's engine heater in at night, your car will be dead in the morning. Cars can be charged from 110v, but 220v is obviously better. Although apartment owners will moan about the costs, running 220v drops to each space isn't going to break them. I'm amazed sometimes about how really useful a 220v/30 amp L2 charger really is. I have two long range cars, a Bolt at 238 miles and a Tesla M3 at 320 miles, and typically they charge up in 4 hours on a 6.6kW L2 charger, because I don't run them all the way to zero, nor is that a good idea. Both of my cars need charging perhaps once or twice a week even with my 40 mile round trip commute. Its not even necessary to purchase a $400 charger. My Tesla comes with a 220v charger free with the car, and its a reasonable cost with the Bolt. With that and a 220v outlet, you are there for at least a 3.3kW charge. I will say that 130kW supercharging is amazing on the road (Tesla). I typically think about charging when the miles left goes to 2 digits (<100), and I see the 100kW+ charge for only about 20 minutes. But that charger takes the Tesla from less than 100 to over 200 miles in that 20 minutes, which is rocket fast compared to other cars, and makes highway travel amazing.
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  50. The high tech description of how a motor works: "the electricity makes it go all spiny".
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