Re: Instead scopes

On 31/08/2024 12:13 am, john larkin wrote:

On Fri, 30 Aug 2024 06:47:54 GMT, Jan Panteltje <alien@comet.invalid>
wrote:
 

On a sunny day (Thu, 29 Aug 2024 11:47:42 -0700) it happened john larkin
<jl@650pot.com> wrote in <pcg1djt6otqheh6vgi9len892jd21g1sn0@4ax.com>:
>

On Thu, 29 Aug 2024 16:21:21 GMT, Jan Panteltje <alien@comet.invalid>
wrote:
>

On a sunny day (Fri, 30 Aug 2024 00:43:39 +1000) it happened Bill Sloman
<bill.sloman@ieee.org> wrote in <vaq1f2$jdj$1@dont-email.me>:
>

It's lot easier and quicker to bread-board a circuit in LTSpice than it
is to wire up a test circuit, but what that means is that you need to
make fewer real circuits and they are a lot more likely to work when tested.
>
That, on it's own, is enough to explain why labs look different today
than they did in the dark ages.

>
All it explains is boeings falling apart and astronuts ending up stuck at the ISS
and no moonlanding from the US, not even a probe.

>
The ISS and moon landings are super-expensive theatre. Neither
accomplishes anything.
>
Boeing and Microsoft have the same problem, bean counter money-mongers
have taken over from engineers.
>

Slimulations are _not_ realty and never will be.

>
Spice can be very handy. As Mike says, LT Spice's real function is to
train your instincts.

>
I dunno, much I learned from working with tubes and transistors was by building small circuits and measuring what happened.
Sure spice is great for math intensive stuff such as filters.. but you still need to know the basics.
These days with chips doing much of the work and limited knowledge what is actually _in_ those chips
it is hard to tell if a real circuit will behave like spice tells you
You will still need real testing.

 Sure, but if I wake up at 3AM in Truckee, I can Spice an idea and go
back to bed.
 https://www.youtube.com/watch?v=x6TrbD7-IwU&list=PLlD2eDv5CIe9u7jbKUkZ5xrLLSCrn0z_e
 Actually, I have designed useful circuits by randomly fiddling with
Spice, stupid topologies that turn out to work.

What a creationist would call intelligent design. The rest of us call it evolving your circuits, rather than designing them, and you have described that as insanely inefficient.

Maybe boeing just spiced their thrusters :-)

 SpaceX is having trouble with helium leaks too. Helium is the chemical
equivalent of slippery eels. It will leak though almost anything, even
solid metals. If they need an inert gas, why don't they use argon or
neon or nitrogen?

Argon and neon aren't all that inert, nitrogen even less so. For thrusters, helium's low molecular weight is a real advantage. Hydrogen would be about the same, but it is anything but inert, and leaks almost as fast a helium, and atomic hydrogen can produce hydrogen embrittlement.
https://en.wikipedia.org/wiki/Hydrogen_embrittlement
--
Bill Sloman, Sydney