Dan,
I've run into that on some metric sized equipment, you look at a weird dimension and wonder why the value is such a strange number and then you realize it is a fractional inch equivalent! Been there done that.
I've run into that on some metric sized equipment, you look at a weird dimension and wonder why the value is such a strange number and then you realize it is a fractional inch equivalent! Been there done that.
Sy,
Is that the same as one liter=61.0237 cubic inches! Yes a good thing to know when working on box size and such.
TBH, I can't think of anything where I use cubic inches.
Jan,
First thing I have to do when doing a CAD drawing is set the type of dimensional units, nothing worse than doing a drawing and finding out you did it with absolute dimensions and they are in the wrong value, a real mess to fix.
Yes but I have to switch now and then, parts and pads are often in imperial and board size, mounting holes etc in metric...
Jan
Hi Ed
Reversing the connection of a coaxial cable (center conductor to ground, shield to signal) always makes for increased noise pick-up for me, especially when more than one instruments are connected in the set-up.
The following screen shots are from noise pick-up tests in my workshop. A very simple (no loops) setup.
A cable connected at the 1Mohm Input of a signal analyzer (10kHz to 200MHz span, linear horizontal scale 20MHz/div)
George
George,
Why don't you try the coaxial cable terminated with 50 ohms and then turn it around so it is still center to center but the connector that was going to the termination resistor goes to the input and the one that was going to the input switched to the dummy load?
Sy,
Most common place is woodworking here in the USA. Just try and give metric dimensions to a carpenter and see what you get. Like my friend a contractor who told me the 3,4,5 rule for seeing if something was square and I said oh you mean A^2 +B^2 = C^2 and he looked at me so funny. What do those guys do when they have to do an angle?
Jan,
Yes I understand that we often have to integrate both value systems, no real way around it but to convert one value or the other. One day we'll all go metric here in the US but I haven't seen any real push to do it outside technical fields.
Most common place is woodworking here in the USA. Just try and give metric dimensions to a carpenter and see what you get. Like my friend a contractor who told me the 3,4,5 rule for seeing if something was square and I said oh you mean A^2 +B^2 = C^2 and he looked at me so funny. What do those guys do when they have to do an angle?
Jan,
Yes I understand that we often have to integrate both value systems, no real way around it but to convert one value or the other. One day we'll all go metric here in the US but I haven't seen any real push to do it outside technical fields.
Last edited:
Ed
I can’t understand what you propose. Please make a drawing.
I was seven hours in the hot workshop (35 + d.C ) collecting data for your setup.
Time for some drink now

George
I can’t understand what you propose. Please make a drawing.
I was seven hours in the hot workshop (35 + d.C ) collecting data for your setup.
Time for some drink now

George
Sy,
Most of them can't count that high! Square footage or cubic footage for say a storage shed or something, but they usually don't do the plans so just follow a drawing.
Most of them can't count that high! Square footage or cubic footage for say a storage shed or something, but they usually don't do the plans so just follow a drawing.
Ed
I can’t understand what you propose. Please make a drawing.
I was seven hours in the hot workshop (35 + d.C ) collecting data for your setup.
Time for some drink now
George
Did I miss your promotion? Congrats or condolences, not sure. 😀
And that's a lot of dedication to experimentation! Enjoy a brew or 3.
TBH, I can't think of anything where I use cubic inches.
Dunno for the US but here engines are rated in cm3 when the volume is below 1 Litre wich is 1000cm3, medical liquids are also rated with this unity.
Oh, we use cc all the time. But other than car salesmen, I can't think of where cu in might ever get used.
recently
(a proper gentleman would help a lady by offering to whip out a calibration tool)
I'm still trying to figure out why a 1/2" pipe isn't 1/2" and why a 2x4 isn't 2x4. In comparison, mental conversion between Imperial, cgs, and mks is trivial.
Hmmmm... is this troll bait?
But anyhow the 2 x 4 is 2x4 when rough cut - the stuff you buy in the store has been milled for finish... and besides they take liberties with them these days making them undersize, presumably to increase yields/profits.
Wacking your cables with either the pipe or the 2x4 will have no positive effects, fyi.
_-_-
But I'm not buying a 1.7 x 3.6 or whatever. They still call it a 2x4- and who the heck knows what size it really was earlier in the process?
As for the pipes, the links I gave speak for themselves.
As for the pipes, the links I gave speak for themselves.
Sy,
Throw in the difference between copper pipe and soft copper tubing and things get even more interesting. what a mess they made of all that.
Throw in the difference between copper pipe and soft copper tubing and things get even more interesting. what a mess they made of all that.
Ed
I can’t understand what you propose. Please make a drawing.
I was seven hours in the hot workshop (35 + d.C ) collecting data for your setup.
Time for some drink now
George
Thanks George. The issue is do cables work the same if you just turn them around. You went to the effort to turn them inside out. On a normal BNC cable we have two ends. Lets call one end "A" and the other "B." So the simplest test is to connect "A" to the analyzer and "B" to a 50 ohm termination. The Connect "B" to the analyzer and "A" to the 50 ohm termination.
The second step would be to use a signal generator about 3 dB above the noise level instead of the 50 ohm termination and try that feeding "B" and then swap it so it feeds "A." Look at this with as narrow a frequency band as possible.
Let me know what you are drinking and I'll send you a bottle!
Thanks for you efforts!
ES
BTY Do be careful I have a friend who ended his vacation in Greece with heatstroke.
Last edited:
When I gave a tour to the big guy from JPL, he didn't mention ego's, just the conversion error when I spoke to him. His brother told him he ""couldn't hit the broadside of a planet...no wait, you did, didn't you ?""As far as the Mars-metric/Imperial snafu: that had less to do with units and much more to do with egos.
Tough crowd, siblings...
Yah, all the IV bags, transfusion products, and syringes are milliliters.Dunno for the US but here engines are rated in cm3 when the volume is below 1 Litre wich is 1000cm3, medical liquids are also rated with this unity.
John
Oh, we use cc all the time. But other than car salesmen, I can't think of where cu in might ever get used.
One more time dunno for the US but here a bottle of whisky is marked either 0.75L or 750mL given that 1mL (milli Litre) = 1cm3, and so is every liquid that is less than 1 litre like aluminium packed coke wich has 330mL marked on the can.
The issue is do cables
…
and then swap it so it feeds "A." Look at this with as narrow a frequency band as possible.
Ah. OK Again in search for directivity clues .

Let me know what you are drinking and I'll send you a bottle!
It is a raki from Creta. They call it “tsikoudia” Good stuff!
E-mail me your address and I’ll send you a bottle.
BTY Do be careful I have a friend who ended his vacation in Greece with heatstroke.
Visitors are in danger of heatstroke. Locals suffer from wifestroke 😀
Thanks for you efforts!
I do it to satisfy my own curiosity.
I’ll post some photos.
Tomorrow I will arrange for the data
George
When I gave a tour to the big guy from JPL, he didn't mention ego's, just the conversion error when I spoke to him. His brother told him he ""couldn't hit the broadside of a planet...no wait, you did, didn't you ?""
Tough crowd, siblings...
There's a hilarious Far Side where it's an alien husband and wife at a back-country gas station (UFO and all) and the guy at the station is looking at their map saying "Man, I could understand a planet, but a whole solar system?"
The wife alien was giving that "if looks could kill" stare too. So funny.
- Status
- Not open for further replies.
- Home
- Member Areas
- The Lounge
- John Curl's Blowtorch preamplifier part II