I'm playing with a program from Power Integrations that designs simple flyback power supplies. I'd like to understand how it comes up with the EMI filter (between the 115/230 VAC input and the primary leg of the transformer). As a general question, what do you use for the impedance of the...
I just put together a switching PS designed with the help (actually it did almost all the design) of Power Integrations PI Expert. It's a 4 W, 24 VDC output, 115 VAC input supply. So far it is working well with our product. I'm running it at elevated temperature right now. I'm wondering what...
I've got a nice brochure from Magnet Applications that talks about making permanent magnets. I need some clarification about how they work in a magnetic circuit. The brochure shows the magnetization curve and states that permanent magnets operate in the 2nd quadrant. I see there is a...
If you took a Belleville style washer (simply supported on the ID) and applied a load to it till it was flat and then increased the load a small amount would the washer "buckle" in the other direction? I think it would but I'm not sure of the internal stresses that would cause it. I'm guessing...
I've got a small shaft that is broken and I'd like to learn a bit about looking at the fractured surfaces and trying to figure out what happened. Are there any good books (with pictures) you can recommend?
Given an BH curve for a material, like low carbon steel, is it possible to predict how far into saturation you would need to go to produce a particular amount of residual flux density?
I'm trying create a gear. It would be nice if I could actually make an involute curve. Is it something that has to be done with VBA? Or could I use a spreadsheet and import it into Inventor?
Chevy says it can go about 40 miles on batteries alone but can go another 200 or so miles using a small IC engine that recharges the batteries. So, in effect, the "small" IC engine is moving the car. I'm assuming that performance (acceleration and top speed) are drastically reduced when...
Is B measured directly or indirectly? To measure directly using, say, a hall effect type probe you would have to modify the sample to accept the probe. The probe then would only measure the B in the modified area (filled with air, not the sample material). So I'm guessing it must be measured...
I know lasers are used to check how perpendicular the movement is for 2 axes on machine tools. I just don't know how you set the laser up to measure this. I understand how interferometry is used to measure a linear distance. How do you use it to measure a perpendicular movement?
I'd like to access my work computer from home. Both are connected to the internet via cable. Both have the cable modem and a wireless router. The only thing I need to do is transfer files. I've read a bit about port forwarding but that looks to be more for playing games on remote computers...
Sorry for such a basic question but I never really thought about waht keeps a satelite at a constant height. You've got gravity trying to pull it towards the earth and centrifigal force trying to push it away from earth. It seems like that is very unstable - a little deviation either way would...
I've only worked with simple freeware FEA programs. I'm looking at purchasing a more powerful package. One thing I'd like to do is see what effect misalignment of mating parts has on stresses. In particular, a vendor of ours made some shafts where the keyway slot was off the centerline by...
The driver won't install for my new wireless PC card network adapter. I suspect something in the .inf file is wrong. Can a driver be installed directly in Windows 2000 without going through the Windows wizards?
I can't get the TF (Transfer Function) analysis to operate properly. It seems to run - a screen pops up briefly (too brief to read) and there are no errors listed. The problem is there is no output graph when finished. AC analysis of the same circuit works fine (a graph appears). I've...
While recently riding on the interstate at about 70 mph I noticed I had some steering wheel shimmy. I figure the tires/wheels must need balancing. But the shimmy would be there for a bit then go away for a bit - maybe even periodic. I'm trying to figure out why. My guess is that at 70 mph I...
A colleague of mine says an electric motor driving a vehicle has an inherent advantage in accelerating the vehicle. I'm trying to figure out why. I'd think the rotational inertia of the electric motor is comparable to the rotational inertia of the internal combustion motor. If you're going...
We have some aluminum disks that we would like to powder coat - but only one side of the disks. The outside firm we use for painting isn't sure how do to this. I was thinking a silicone rubber block with counter bores that the disks would press into. My question is grounding. Do I need a...
I haven't had to design much mechanical fixturing for awhile. I used to just use the criteria that I wanted my mechanical fixture resonances to be above the fundamental excitation frequency the fixturing would see. Now I need to design a fixture for holding a part in a milling machine...
