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Crowd Funded Projects / Re: Electromagnetic Interference Theory
« Last post by cleaningOut on Today at 06:33:27 PM »
It's not that he's crazy or a crackpot. He's just incredibly stupid. Maybe reading a textbook would help him.
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Crowd Funded Projects / Re: Electromagnetic Interference Theory
« Last post by Simon on Today at 06:30:45 PM »
oh this is hilarious, I could not even figure out what he was on about in that childs scrap book. Look mate I'll leave this thread for now for entertainment value, start another one and your banned!
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Beginners / Re: AC power in a multicore cable
« Last post by Brumby on Today at 06:27:24 PM »
Multicores tend to be somewhat longer than a metre.
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I am in the market to buy a new car right now.

I am a technology person and would like to buy a full electric vehicle, but as much as I like them, the technology is just not there yet.  They are a burden to own compared to a gas car.

They require you to think and plan and work around them, whereas a gas car does not.  I am actually not convinced that battery EV's are ever going to succeed until we have a revolutionary battery technology come along.  What we have now isn't it.  Even with supercharging, I don't want to sit for a half hour to charge when I can fill up with gas in 2-3 minutes. 

There is always a knee of the curve, a killer app, a price point, or a threshold that needs to be met before a technology really catches on.  VCR's could do time-shifting for years, but only when digital storage made it really easy did it take off.  And only when EV's are as convenient as ICE cars will they take off.

Until then, they will be bought by tech savvy early adopters willing to live with the (severe) shortcomings and by people who like getting $10k of their fellow taxpayers money for their luxury car.

like most people you are not being imaginative and expect a like for like replacement. So where do you work? does your employer have roof space to put solar panels on so that you can charge your car while at work? there are cars capable of 200-250 miles. If my employer made at work car charging a thing I'd buy a second hand electric tomottow aqnd travel for 1/10 the cost I do now plus have juice to plug the car into the house and run the house for free..........
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Metrology / Re: Low ohm precision resistor standard and testing
« Last post by Micke on Today at 06:22:27 PM »
...
Will put it in an aluminum box with four binding posts, high current binding posts will be 63A rated, Kelvin output will be a dual gold plated 19mm spaced version  :)

Thanks for the heads up on the 300 gramm weight, I did not see that.

I ordered two of these Isabellenhütte resistors, too good of a deal to not take advantage of.
And I also wanted to put one in a box with binding posts and separate Kelvin output to good quality binding posts.
What gold plated bindings posts will you be using?

But why are you planning to have a "dual" output?
May be something to consider?


I wrote a little bit confusing I realize now... I will only have one output, a couple of years when ELFA had a big sale, I bought very nice gold plated double binding posts very cheap (think they are USA made) 
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RF, Microwave, HAM Radio / Re: FT-817ND cost down?
« Last post by Diabolo on Today at 06:02:08 PM »
Hello,

Here is where to buy 1 TCXO-9 for Yaesu.
- https://www.ebay.fr/itm/Compensated-Crystal-Components-Module-for-YAESU-FT-817-857-897-TCXO-9-22-625MHZ/142288127481?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

For example, Yaesu filters can be found on Ebay.
- https://www.ebay.fr/itm/YAESU-YF-122S-2-3KHz-COLLINS-S-S-B-MECHANICAL-FILTER-FOR-FT897-857-817-RANGE/322897702800?hash=item4b2e33ef90:g:gUoAAOSwTM5Y22j3
----
FYI, I installed 1 TCXO-9 in an FT847.
To feed correctly this TCXO I built in smd 1 stabilsée power supply with filter starting from 8V general: 10uf tantalum, 100 nf ceramic, regulator 3,3V smd, self of 10uH, 10 uf tantalum and 100 nF ceramic.
I also built in smd a 22.625 mhz output filter: R10 K, 18 pf, self 4.7 uH, 15 pf.
The whole thing (3.3v power supply and 22.625 mhz filter) is wired under the TCXO-9 board which I "etched" with a fine dentist's cutter.
To have room I replaced a capacitor cms 10uF Yaesu that did not generate a smd 10uF tantalum.
The TCXO board is 6 mm above the Yaesu Control Unit main board, and the 2 (V+ and F out) connections do not exceed 1 cm in length.
Of course I deleted R1111 (2k2) and R1109 (100 ohms).
I have also made all the existing modifications for the Yaesu FT847 to improve it.



73's
Diabolo
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Repair / Re: Low noise fan for HP 3458A ?
« Last post by TheSteve on Today at 06:00:37 PM »
A week ago I swapped out the Papst 622L for the Noctua NF-A6x25 in both of my 3458A's. The noise of the Papst fans was just too annoying in my house. They had a bit of a "whir" sound to them that I could hear a long distance away. The Papst fans are only a year old or so and are the proper spec'd fan however I am pleased with the Noctua fans so far. They have only a nice "shhh" sound to them. The 3458A's internal temp sensor does report temps 3 to 3.5 degrees C warmer with the Noctua fans so they clearly move less air. During a bench test they also drew more power then the Papst fans. My ambient temp is usually around 20 degree C so temp isn't an issue at all, if you are in a hotter area you might want to stick with the Papst fans.
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General Chat / Re: New LED bulbs pulsing when off!!!
« Last post by Falcon69 on Today at 05:59:24 PM »
to the OP

This is so funny that you say they are pulsing, and seems those are house bulbs.

I just bought some LED bulbs for my truck. When I turn the lights off, they pulse and flicker as well. It's weird sometimes. Almost like the strobing of police lights. I wonder if it has something to do with the automatic light function of the truck (turns on when it starts getting dusk outside).

I even tried manually turning them on and then turning off when I turn the key to the off position. They still flicker.
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Projects, Designs, and Technical Stuff / Re: The uBeam FAQ
« Last post by amspire on Today at 05:56:15 PM »
It make me angry. I have had to recently deal with some old people who are loosing their eyesight with things like macular degeneration and diabetes.

Hearing becomes everything. You would hope that if uBeam becomes anywhere near to implementation, rules limiting continuous ultrasound levels in home/office/public situations to 80dB would be implemented.

Where is the due diligence from the investors? I hope the only future uBeam lawsuits will be from mislead investors, and not from damaged people.

The only good news is that uBeam promises become more and more feeble with each round of fundraising. 0.6W at 1 meter? Have you got to keep the phone pointing to the transmitter at a distance of 1 meter to just maintain charge? In what way is that "freedom of movement"?
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Beginners / Re: Modifying PSU to provice 5V output
« Last post by ogden on Today at 05:53:52 PM »
You can get DC-DC converter modules based on LM2596 assembled, tested and shipped for $0.78 on eBay. Worth to reconsider building such. Better make some really exciting stuff.
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