Electrical Engineering

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W5VO

2:08 AM

I've also seen holes ripped through metal plate because a capacitor bank found a short.

12 hours later…

EwokNightmares

1:52 PM

@W5VO ok but how does this happen? what is the nature of the force sending them flying???

is it an arc blast pressure?

placeholder

2:35 PM

Morning all

3 hours later…

Salehen Rahman

5:14 PM

I just want to double check: is it possible to reconstruct a time domain "signal" from a frequency domain "spectrum"?

Even though it's stupid (I really should be using an FFT and an inverse FFT for this), but what I'm asking is, is it possible to just look at the output of a DFT, and reconstruct the original signal, just by summing the manny sine waves represented in the frequency domain spectrum?

The Photon

@SalehenRahman That is essentially what an IFFT does.

One thing --- you must have both amplitude and phase information in your spectrum.

Salehen Rahman

@ThePhoton thanks!

4 hours later…

W5VO

9:01 PM

@EwokNightmares Rapid vaporization of metal?

I'm really getting frustrated with picking magnetics... I feel like all the datasheets are telling me is that I'm getting a piece of ferrite wrapped with a certain length of wire... and nothing else.

The Photon

@W5VO C'mon, they also give you an Isat, don't they?

Is this for power or for RF?

'cause choosing magnetics for rf is the worst. They still just give you L, Isat, and a bullet point like "designed for high frequencies".

W5VO

@ThePhoton PoE magnetics, and transformers for SMPS

The Photon

You're lucky if they give you any idea what they mean by "high"frequencies. 10 MHz? 100 kHz?

W5VO

especially because I'm wanting more power than the PoE spec allows

The Photon

@W5VO Well, then at least you'll get a bullet point like "designed for PoE".

W5VO

9:14 PM

@ThePhoton "High Frequency" means that it looks good on their 1kHz LCR meter

I'm not bitter at all

The Photon

@W5VO Gonna find out how many amps 28-guage wire can carry?

W5VO

@ThePhoton If I can get up to 400mA then I'm pretty good

but that takes CAT6, and the system needs to be designed for it. Not a problem for me, but it's harder to find solutions

I think it's 24AWG for CAT5, and 23AWG for CAT6

but the pulse transformers for Ethernet have very few current ratings

and how do you even pick SMPS transformers with the tiny bits of info they give you?

The Photon

I shouldn't joke about this. The datasheets that come from my organization are more of an invitation to call us if you want to buy more than 1000 units/month --- we'll send an FAE right over. Otherwise, be glad we told you the name of each pin and how many parts we ship on a reel.

W5VO

@ThePhoton ...mumble... it'd be cheaper to spend 20 minutes on the datasheet than a full-time FAE... mumble...

The Photon

I'm shopping for FPGAs. For the price of a new car you can get an FPGA with 28 Gbps i/o's.

W5VO

9:29 PM

Is that the one with the direct fiber interface to the top of the chip?

The Photon

@W5VO I'm told that one was a bit of a kludge.

Clever demo though