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To: Mchristian who wrote (46021)8/28/2017 11:23:38 PM
From: P2V
   of 46079
 
HI ,
My first and probably totally ignorant thought is that you may have created a ground loop. between the two assemblies.
ground loops (twin ground connections make fine 60 hz hum pickups .Our surroundings are saturated with 60 HZ sine waves.

going back to audio days .... such problems were eliminated by connecting all device grounds to one common point.(ground) or earth

I once made the mistake of looping a ground from one device to another (in a string of devices)
Believe it or not it happened to be an old IBM Selectric printer (flying ball) to which I affixed a printed circuit board of my own making.

Nothing worked , as stray pulses, as detected with a hand held pulse detecting tool, abounded at all points on my ground wires


A quick look at an Arduino controller + 3 phase servo /motor ... shows that the common point of the 3 coils ,
is completely isolated from the controller's ground..(external earth connection)

Am not a software guy but I date back to machine language routines,
but I would guess that if your software routines worked OK before, they should be working OK now

Hope this is not totally off the wall

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To: Mchristian who wrote (46023)8/29/2017 9:27:13 AM
From: P2V
   of 46079
 
BTW have you looked at: WWW.ELABZ.COM/BRUSHLESS-DC-BLDC-MOTOR-WITH-ARDUINO/ ??

(either directly into your browser of google)

I would look at part two.... circuits and software.

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From: elmatador9/5/2017 6:53:34 AM
1 Recommendation   of 46079
 
We do for retailing what Amazon cannot do


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From: ftth9/5/2017 3:22:20 PM
1 Recommendation   of 46079
 
Voyager 1, Humanity's Farthest Spacecraft, Marks 40 Years in Space

: Article

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From: axial9/6/2017 12:04:34 PM
1 Recommendation   of 46079
 
Sun Unleashes Monster Solar Flare, Strongest in a Decade



'Early this morning (Sept. 6), the sun released two powerful solar flares — the second was the most powerful in more than a decade.

At 5:10 a.m. EDT (0910 GMT), an X-class solar flare — the most powerful sun-storm category — blasted from a large sunspot on the sun's surface. That flare was the strongest since 2015, at X2.2, but it was dwarfed just 3 hours later, at 8:02 a.m. EDT (1202 GMT), by an X9.3 flare, according to the National Oceanic and Atmospheric Administration's Space Weather Prediction Center (SWPC). The last X9 flare occurred in 2006 (coming in at X9.0).

According to SWPC, the flares resulted in radio blackouts: high-frequency radio experienced a "wide area of blackouts, loss of contact for up to an hour over [the] sunlit side of Earth," and low frequency communication, used in navigation, was degraded for an hour. [ The Sun's Wrath: Worst Solar Storms in History]'

Jim

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To: axial who wrote (46030)9/6/2017 5:42:36 PM
From: ftth
1 Recommendation   of 46079
 
Thanks for posting. Here's a time-sequence animation from still pics:
LINK


Probably caused by North Korea ;o)


Difference between solar flares and coronal mass ejections (CME): LINK

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To: axial who wrote (44934)9/7/2017 1:24:00 PM
From: axial
1 Recommendation   of 46079
 
Hurricane Irma boosts downloads of walkie-talkie app Zello

Does Zello Work Without Internet?
— The Zello app can be useful in an emergency situation, it still requires the internet to function.

Jim

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To: axial who wrote (46032)9/7/2017 10:13:58 PM
From: Frank A. Coluccio
   of 46079
 
I've been meaning to post on the general topic of first responder communications during Harvey. Maybe I'm just not looking in the right places, but there seem to have been scant little discussion in the trades and blogosphere, compared to the furor that arose after 9/11/2001, and then Katrina. Does anyone have a handle on this subject who'd like to share it with the board? What will be the main mode of communication during Irma? During Irma's early trail of devastation, as it knocked off one island after another, the main fallback has been satellite phones, as the bulk of cellular towers have crumbled to the ground.

------

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To: Frank A. Coluccio who wrote (46033)9/8/2017 1:16:10 AM
From: Elsewhere
1 Recommendation   of 46079
 
Richard Branson uses a sat phone on the British Virgin Islands.
"I'm speaking these words from a satellite phone that is just about working, but all other communications are down."
virgin.com

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To: Frank A. Coluccio who wrote (46033)9/8/2017 5:24:06 AM
From: axial
1 Recommendation   of 46079
 
1 — Harvey Shows Progress on Emergency Communications Since Katrina

'One comparison offers a glimmer of hope amid the devastation: Communications networks have held much better. While connectivity was almost completely lost in Rockport, Texas, which was hit hardest by the storm, the Federal Communications Commission says just 4 percent of the 7,804 cell sites in Harvey’s path were wiped out, affecting 148,565 people. By contrast, more than 1,000 cell sites were knocked out during Katrina, preventing millions of calls from going through, according to a post-Katrina FCC report. Now, Texas’s 9-1-1 system has been overloaded with calls, but “those calls are going through,” says Adm. Jamie Barnett, former chief of public safety and homeland security at the FCC. “By and large we’re hearing that the cellular networks stood up. That means there’s been some learning.” '

2 — Hurricane Irma: Prepare your smartphone for catastrophic conditions

3 — And of course, Old Faithful — HARVEY AFTERMATH: Ham Radio activated for emergency communication

With Harvey wind was an early but transient issue. The longer-term problem was rain, not so destructive to towers. Irma's +200 kph winds will probably tell a different story.

As noted a few years ago, first responders have their own dedicated channels and protocols, which will be tested. As long as there's non-tower internet connectivity WiFi remains usable for the great unwashed.

Jim

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