Yes George slip is very important not just in generators but also in lift motors. I had an arena cluster that was lifted by eight hoist motors. In the design I included strain gauges to monitor the load on each motor. What I learned is that if a motor ran a bit faster than the others, the load on it increased. This caused it to slip a bit more and slow down sharing the load better. In this country with 60 hertz AC power a motor should of course run at 1800 RPM. Most are actually 1725 RPM due to slippage, some 1750 others 1700. The hoist motors were rated 1680! So the hoist guys clearly knew what they were doing. Efficiency was not much of an issue with the infrequent use, but load sharing played a big part.
Yes I have played a bit with generators. One of the issues is that they do not produce pure sine waves as there must be a gap in the magnetic material in order to get the windings on!
Now what I find interesting is the mis-application of the maximum power transfer bit. There really was an audio consultant who used build out resistors to make sure all his sources actually were 600 ohms and then termination resistors to make all the inputs became 600 ohms.
As most sources are around 100 ohms this placed 510 ohms in series with most gizmos. Input impedances are almost always 10,000 ohms so a 620 ohm resistor went across these. He in his entire career never got it that he did not have maximum signal to noise with these "improvements." He "Knew" that maximum power transfer occurred with matched source and load impedances.
In AC power generation and distribution the goal is less than 5% loss and never more than 10%. Certainly not possible with matched impedances.
I recall I preferred 10 percent remuneration fee on the first, on taxi rides to the airport, on 'night club' and casino clients, and 20 percent on 250-500 buck/hr escort hookers
(male/female/inbetween/mix, per each hour. my personal record is 800 for a single John phone call investment of under 15 minutes)
The 2nd, I personally delivered for 2.5 times the retail bottle, whichever the content.
A commercial mind is open front and back on all hours.
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But most of the protaganists on this thread are well capable of measuring incidental rf effects, and let's face it they are rare, especially 50kW local transmitters.....
I'd hardly call rf events rare: how about a cell phone in close proximity to your home electronics?
50 kW close by and the dielectric loss known as you becomes a big deal (simple heating).
(Much of it should be well attenuated by everything in between you and it, though)Jacco, I don't know the dielectric loss factor of rockwool to cell phone frequencies, but it might be fairly significant, especially if it's humid (the rockwool will have a lot of -OH to adsorb a thin layer of water).
https://www.youtube.com/watch?v=8oFX7IgLlDk
RH in my home is monitored 24/7 (for a reason)
The Rockwool is only in the ceiling and floor, both wood, 8''x3'' beams.
The Hawaphon is in/on all six surfaces, two layers in the door to the hall.
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Well designed audio components with well designed interconnecting system must pass this test without any audible effect in the speakers. If not, something was done wrong
Well GSM is on the way out in many countries so the 217Hz frame rate is not heard as much. And as said anything that picks it up is failing EMC. Filtering RF at the levels I would want to be in the same room as for long periods is not hard to audio noise floor levels.
Well in a country where the roads go under the canals high humidity could be seen as a bad thing
Well designed audio components with well designed interconnecting system must pass this test without any audible effect in the speakers. If not, something was done wrong
100% agreement. It's, if anything, a frustration of mine to see people eliminate RF filters from the ends of schematics to "simplify" the diagram. I wonder how many times they're left off entirely in ignorance.
It's more important now than ever to manage RF around your electronics--scads of signal hanging out up there (although probably better managed now than before).
Extremely cost-challenged products used to just put up with cellphone interference. I may have told the story about a Harman three-piece powered speaker system which was immune, through no fault of mine
. It had discrete bipolars in the pseudo-surround processing and front end, which normally would have been efficiently rectifying the RF. But probably owing to the high quiescent currents and possibly some fortuitous board layout details, it was actually immune without common-mode chokes or shielding.
After 1993 it should have been tested for CE (sorry poor taste joke there*) or relevant FCC stamp? Anything made pre 90 was fair game for the boop-de-doop of a phone.
* Yes CE is a joke. If risk of sue=low, just slap the logo on.
Looking at the construction of this might give you some hints about why you're losing cell coverage.
Upside, no one will distract you now!
My home has several cellars, reinforced concrete walls of 8'' thickness, integrated with the ring foundation and concrete floors inside.
2 of them are former coal cellars, below what used to be the kitchens at the back of the house.
Each sizes about 10' x 14' with ~6ft height, 20''x24'' drop-opening with a metal hatch on the exterior.
Coal dust turned the concrete of the walls rather gloomy over the decades.
I've flooded them twice to pump the slurry out with a submersible dirty water pump, afraid the walls require a hot high-pressure cleaning to look more presentable.
Not much more suitable for recreational purposes ? Need a pic ?
(there are bedrooms above my auditing room. kids and wooden floors, you know)
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