Standard Resistor Values: Why not a true geometric series?

Bullshit. You can buy spark gaps at various breakdown voltages.

I can see it now... setting up a ten ton die press to punch out holes in PCBs, nearly all of which are different from each other.

Whereas a CNC drill head can dance around any plane, popping holes at will for one tenth the cost.

The press can punch the entire pcb - all the holes and the outline - in a single hit, maybe a board a second. For a small breakaway array, one whack can bunch dozens of boards in one second.

It has to drill a hole at a time. 100 holes may take a full minute to drill. And then you still have to route or punch the outline.

John

But those are gas-filled. Got a link to anybody who sells vacuum gaps with defined breakdown?

John

Do you know how much it costs to machine a press die?

Do you know how little it costs to program a drill routine, and then let it run?

Also, if the press can gang punch a hole, the drill can certainly do so as well.

As Spock would say, "Kahn's behavior appears as if he thinks in only two dimensions..."

You need to add the Z dimension to your thinking, Dingus Con.

In , ChairmanOfTheBored said in part:

I do consider this true, and a rare moment when the "gentleman" (??? at best) says somethjing worthwhile and true.

I even have found some web search traces of 30 milliamp neon sign transformers achieving a bit of a body count!

Most references for amount of current to cause electrocution in an arm-to-arm shock tend to say 100 mA to 1 amp for AC of 50-60 Hz. However, that appears to me to be a fairly wide band, and lesser but still-above-zero chance of electrocution via ventricular fibrillation exists for a substantial range of current outside the 100-1000 mA range (for arm-to-arm shock at 50-60 Hz).

For that matter, a few references say that the danger of electrocution gets high at 50 mA.

To go further, I do want to say that lesser but nonzero to maybe significant chance of electrocution exists at much lower current, and in the past 26 years I have seen a bit saying that there is a bit of a chance for someone to get fatally shocked at about 5 mA, without resorting to penetrating the skin with electrodes.

To temporarily digress to efects of high current (above half an amp to an amp or so) - probability of the deadly ventricular fibrillation is less than at 100-500 mA or 100-1,000 mA or whatever, but higher current does give some chance of outright cardiac arrest - also lethal!

Another item notable: Various actual causes of death for those executed in the "Electric Chair". The amount of current gets on the high side for higher chance of ventricular fibrillation. There is sufficient unreliability in electrocution for "capital punishment" by electric shock to mostly be done with such high voltage and such high current that the "comdemned" has heart and/or breathing muscles paralyzed long enough to deprive the brain from oxygen long enough to impair recovery of both breathing and heartbeat. Beyond that, the "Electric Chair" resorts to outright cooking of vital organs!

On an extreme note, I have seen bits of some chance of electrocution in extreme bad cases from 5-6 mA without skin penetration, and from AC of 60 or 50-60 Hz!

As unreliable as electrocution is, lack of electrocution from a marginal to "safe by a smaller margin" shock is similarly unreliable!

How people can get killed by electricity and by how much current trumps need to disagree with a chronic pest!

- Don Klipstein ( snipped-for-privacy@misty.com)

Sure, I punch my own current shunts out of sheet manganin, using an EDM-machined punch/die set. But it's a lot cheaper in asia, and just an array of holes is an easy punch/die set. A Spehro says, warmed phenolic is soft and easy to punch.

If you're going to do a million boards, the punch/die set becomes worthwhile.

How do you gang drill a hundred holes?

And you need to stop trashing all the things you obviously know nothing about. Hell, you might accidentally learn something.

John

Surely. Even for one or two orders of magnitude fewer, depending.

The Excellon-style drills handle a number of holes at once (in different panels), but I`ve never seen a PCB drill that drilled more than one hole in a single panel at once. It`s done for automated machining setups (hard tooling), but the hole-to-hole distance has to be large enough for the collet or whatever holds the drill and, more importantly, the spindle bearing OD.

Best regards, Spehro Pefhany

Stack 20 PCBs together and drill 5 holes.

Come on, Dimmie's only off 2-1/2 orders of magnitude.

Not only is Dimbulb number-phobic but it's clear he doesn't even know Ohm's law. Some engineer! LOL!

ChairmanOfTheBored snipped-for-privacy@crackasmile.org posted to sci.electronics.design:

That is way past normally optimistic on registration.

krw snipped-for-privacy@att.bizzzz posted to sci.electronics.design:

Actually, based on his track record, i rather suspect that he is the janitor where these activities have gone on. He can learn almost enough to spout the jargon and impress the other janitors, but nowhere enough to con any regulars here. All readers stand by for a raging, cussing streak.

Bullshit. Machined stacks of sheet media are regularly machined, including drilling operations to sub-thousandth tolerances.

You are both absolute retards.

The KeithTard cannot even spell the word "brewing" and you cannot even capitalize words which are supposed to be capitalized. You are both idiots.

Put that in your mop buckets and slop it around.