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5:03 AM
@TonyStewartSunnyskyguyEE75 I was thinking force in pounds not so much magnetic flux density. The magnetic flux density changes that force in pounds relative to the distance and shape of the field produced. The weight, or in this type of case pressure, sometimes called tension can become a factor in solving heating problems.
@TonyStewartSunnyskyguyEE75 Do you have the maximum threshold force for the coil you're wanting to use? The maximum Tesla measurement for the highest magnetic flux points? How long is the hand held paddle going to be used for? (I'm looking for ontime in minutes)
@TonyStewartSunnyskyguyEE75 At this point I want to help you and make this an oppertunity for me to learn more about the pulsed system you're wanting to use. Right now I don't have very much information to go off of to help you much farther. The answers to the questions I asked you will help me understand more about what you want to make. So I can help you more with what you want to make.
@TonyStewartSunnyskyguyEE75 I'll give you my business email so you can give me the whole picture of what you're wanting to make. You can contact me here: scientistsmithyt@gmail.com I usually respond within an hour.
 
 
10 hours later…
2:55 PM
Is 6000 W per day reasonable for an Arduino and some sensors?
 
eBay search sucks.... just sayin'.
 
@adamaero units don't make sense
in general, 6kW is a a ton of power, 1W max is more typical for sensor setups (and you can probably go much lower)
 
Ya, I realize in retrospect a J/second per day doesn't make sense
 
@TonyStewartSunnyskyguyEE75 Well, not a magnetic guru per se, but I do see a lot of shoot-through current through the "off" device. You may be better served by a NFET H-bridge with suitable drivers.
or a single half-bridge pair if you keep the differential supplies
 
Yes of course . That was just trying to emulate the standard SINUS PULSE at 1kW or more
using a split half -bridge
 
3:04 PM
ahh, cool. It wasn't clear where the thermal issue was.
 
If you wave over the FET the kW levels were too high
even with low RdsOn
at 100A
I need > 1 Tesla into 10uH?
how much current and turns air core. hmmm
That level will cause axons to reach Activation threshold and contract muscles which I need to heal crushed nerve bundle in my arm
after surgery
 
ouch, that's terrible!
 
The HW exist already and was developed in EU in Slovenia... Look it up... TESLA STYM
so I have 3 dead fingers
after 2mos post op with a plastic sealing rise time of 3 mos breaking off nerve communication
So I discovered this tesla
but yet not here ...in Canada or USA?
33 Hz seems to be sweet spot for excitation
 
Is it something where you're shooting for an exact field, or a precise field - time relationship?
 
yes to duplicate Central Nervous pulss
but magnetically stimulated withoput electrol-stimulous pain
pain free BH pulse not E Field
the ESP looks like a cattle prod to do the same but patient resistance is high to electrcution
this is a game changer for nerve therapy
if not too badly severed or crushed
 
3:13 PM
Every time I hear someone link their research with Tesla, I worry - Tesla was a genius, but a lot of his ideas didn't pan out, and a lot of people try to ride on his coat-tails.
 
SO after my arm bypass and thrombectemies ( roto Rooter) My Plumbing is perfect 93% Blood pressure to finger tips but median nerve bundle to 1st3 fingers is 99% dead
Dozens of therapy sites use in EU, and like MRI its magnetic
so its ironic I have an electrical problem in my arm that took months to grow or years then triggered with no pulse 9 weeks ago
now great pulse but dead fingers,, numb sore , weak
but I have a plan.. and I will restore it
 
So the thermal issue is with the MOSFETs, right?
 
but 3mos is the healing window ... afterthat 2 yrs maybe but very slow with alot ofg physio
yes
I think I need to go much lower pulse width alternating pulses rather than 50% PWM
but retain SINUS current shape
 
So looking at the waveforms, you're always running them in saturation, beyond 100's of amps.
 
yes
but notquite
need to fix shoot thru bias
 
3:18 PM
and that's a big issue as well, once the pulse diminishes
100+A because the source node is floating around.
 
do you need it in a Helmholtz coil arrangement to maintain a uniform field?
 
thats the unit .. just a small fan on paddle
small spiral large coil
cup size
non uniform focal centre
maybe air gapped??
2.5 T
 
I wonder if it's a "spec sheet half-truths" thing, where you might only be able to get 2.5T at the minimum repetition rate (1Hz)
Does it need to be bipolar current pulses?
I'm not sure you can get that kind of field with 10uH... (and practical currents)
 
3:45 PM
Wikipedia has good formulas for solenoid magnetic fields ( en.wikipedia.org/wiki/Solenoid ). I think if you wanted to concentrate the magnetic field, you may be able to make a gapped core that you can fit the affected area in, but getting those kinds of rise/fall times will be hard
you may need to have a full H-bridge circuit driving just the inductor (that shorts out the capacitor, or floats it).
The L(di/dt) parameters will be difficult, because you probably have an upper limit of 1mH to get similar rise times, and the voltage could easily be another knob to get you another order of magnitude.
I've got some ideas to get you on the right track with the electronics if you're interested, but I don't have the time to go through the magnetics equations and optimize those for your needs.
@TonyStewartSunnyskyguyEE75 Best wishes, feel free to drop by with updates
 
4:32 PM
TY @W5VO. The LV resonance is ~ 300 Hz Q= 0.5
LC
To 400 Hz
 
A 14 Ah battery at 0.01A will reach 0 V or 10.5 V after 1400 hours?
Never mind.
 
5:03 PM
Amps X Volts = Watts

200 amps X 12 Volts = 2400 Watts

Five (5) 100 watt solar panels will produce 500 watts in an hour

In 5 hours you will have 2500 watts - more than enough to fully charge

Right?
 
 
1 hour later…
JRE
6:23 PM
@adamaero Five 100 hundred watt solar panels will produce 500 watts. If you leave them in the sun, producing 500 watts for one hour, then they produce 500 watt hours of energy.
If you leave them operating for five hours, you will get 2500 watt hours of energy.
 
 
1 hour later…
7:52 PM
Any recommendations for cool international radio frequencies to listen to?
 
8:02 PM
Maybe any satellites that are easy to pick with a ~2m dipole?
 
 
1 hour later…
9:03 PM
@W5VO Wait wait, what about 250 Watt-hours/day?
6000/24 hours = 250 W-hr/day
 
9:27 PM
So ~6000 Watt-seconds → 250 Watt-hours/day
(The "6113 W" should be 6113 W-s.)
 
10:04 PM
@JRE A guy I used to work with would ask "What's the difference between power and energy?" as an interview question.
Many candidates, with BS or advanced degrees, would not be able to explain it.
Engineering candidates.
I asked it a lot for new-college hires or internship hires, and my candidates maybe got it right 50% of the time.
 
But that's true for like every discipline.
 

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