@ThePhoton thanks for your advice. And thanks to @Asmyldof too! Your wisdom, freely provided, is worth a lot to me

I just realized that i have 0.05" pitch connectors, and this makes the ribbon half of that. 0.025" pitch. Anyway I have re-scoped all my signals and I see much more realistic square waves, no ringing is going on. In fact they do look a little rounded already.

due to capacitance I assume

Could be. Could also be the probes are detuned

it has a cool self-tuning sequence, its probably about time i did that actually

@KyranF Those are either very fancy probes, or you mean the device itself. Probes often have a tuning pot in the probe or connector.

Bah

@Asmyldof the device itself can self-calibrate. its not super accurate or anything, and wouldn't be anything near a high quality scope in any case. it's a $300 "DSO Quad" pocket oscilloscope with mini-probes

the probes it comes with (plus the sampling circuit) turn out to have seriously low impedance and high capacitance - all the worst traits for low drive strength circuits

@KyranF o.O

I'm not going to offer to lend you some, or within a week I'll have no HP probes left

@Asmyldof Got the mat cut to size/shape and ground wire attached.

I have a BK Precision 2190D with x10 probes and that was able to help me diagnose my circuit and work out that my pocket DSO is a load of garbage

@KyranF So the pocket DSO would be a "Schätzeisen." Like a shooting iron except you use it to make quick guesstimates instead of quick draws.

@JRE that looks a bit like a kitchen table... And a nice modern scope... Does it have triggers? ^^

@KyranF surprise

@JRE Looks like a job well done!

@PlasmaHH That used to be our kitchen table. Yes, the scope has triggers. Don't make fun of it being old. It is exactly as young as my wife.

@JRE keep a few of the cut-offs in case you ever want to make conductive (black side) or dissipative (green side) trays for things

That's what I'm planning to do with my PnP project, make vibration trays with pieces of matting laying on a contact grid, so I can tip in un-taped components and have it place them anyway

@JRE I feel a bit guilty about sending newer/younger spare parts for the scope now. Afraid of what it might insinuate

@Asmyldof The table has a rail along the left side that was used to join it to the cabinet when it was still in the kitchen. I took it off, and soldered brass washers to the ground wire and to the connection for the grounding strap, then screwed the rail back down with the washers around the screws between the mat and the table. I think the connections that way are a little more solid than the crimp on snap connectors. I also put a banana jack in the rail for the ground strap.

@JRE As far as I could measure the snap connectors have <20Ohm connection to the black rubber if you fold the tips inward. Compared to the 20~50MOhm per square, that's fine :-)

But better is, as the word suggests, better

The strap (at least the 5 I tested) has the appropriate 1M resistor which doesn't spark up to 400VDC AFAICT (...Could Test)

@JRE at least you have a nice three phase connection near the table, mine is three floors away

@Asmyldof Don't feel guilty. Both take a bit of upkeep. And (as you can see from the scope) I'm not big on replacing things.

@Asmyldof Electrically there probably isn't much difference. Mechanically, I feel better with things screwed down tight.

@JRE Fair enough :-)

@PlasmaHH 3x64A cable can't be that expensive, not even in Germany

Else I could have added 25mm2 single conductor wire to the package....

@Asmyldof no, but the wife screaming could be a problem

Surely you have a day off that the wife hasn't? If you do a decent job of drilling it through 3 floors in a corner, she'll never know!

@PlasmaHH That's the back door behind the brown curtain. The 3-Phase is there so I can run a cement mixer, or heavy saw, or welder on the patio behind the house.

Going home now. Getting hungry

@Asmyldof That ought to be fun.

if anyone is interested in how I measure duty cycle in ltspice, or has a suggestion on how to do it better: pastebin.com/0aV9wAQi

@JRE Hope it will be.

@JRE @PlasmaHH While paying for dinner, I saw both transfers have arrived safely

@Asmyldof Good. I'd hate to think I carved up a piece of antistatic mat that still belonged to somebody else.

hmpf, I seem to be too stupid to build a simple 555 circuit that I already built thousands of times...

@JRE :)

ok, now that is funny, I once ordered a cheap bag of 1n4148 diodes... turns out, its a bag full of 2.7V zeners...

In other news. The local Sushi Place is serious about their business. Delivery 11-24 Mo through Sun

@Asmyldof Never had pickled herring sushi before

@ThePhoton We could ask @Asmyldof and @Jippie to send is some pickled herring, then we take it to Sushi Tomi in Mountain View, see what they can do with that.

If it works out, they might come up with a cute name for it... EE roll... Netherlands roll... Atlantic roll...

@Asmyldof is the bubble wrap just green or antistatic too?

@PlasmaHH Just green

Recycled plastic

@NickAlexeev @ThePhoton probably better as a cleanser like pickled radish

@Asmyldof Banchan!

this day is used, I want to give it back...

I remember very well receiving some thermal putty stuff in a certain package, and there should be plenty left, but I cant find it...

@PlasmaHH Or ga ni sa tion

I heard of that thing, its pretty new, I should wait if it will stick around

@PlasmaHH Never visit

:-P

Folks, can anyone recommend thermally conductive underfill material for flip-chip? (The chip is 6 x 6 mm, if it matters.)

No experience with requiring that myself

Other than to ask if you have an estimate of the exact thermal conductivity you need?

@NickAlexeev Ask your assembly shop? Vendors I've heard of are Abelstik and Hysol (IIRC).

I want six PWM pins to operate at 20Khz frequency, any idea how can I get that with Intel Edison? is there a way to possible increase the number of PWM pins at this frequency ?

Datasheet?

cdn-shop.adafruit.com/datasheets/EdisonDatasheet.pdf

Yes, but I want 6 PWM pins

at 20Khz

to drive six motors

You'll have to do it in software then

Are you aware of any alternative to Intel edison that has good wifi connectivity with this amount of PWM pins ?

No

Why is it always that more powerful devices like Intel Edison and many others, have less GPIOs and PWM pins than regular MCUs. It is very handy for prototyping :(

@codinginsane Can you reduce frequency and bang the PWM in software?

You could look for controllers that can take high level commands and do the PWMing. You might be able to find controllers that integrate the power FETs and other useful things.

The people who invented the "Direct-Attach Cable" should have thought about whether their acronym was already taken before they called it that.

@NickAlexeev what keywords can I use to look this up?

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