Magnetic disturbance

The magnets they use for that are usually the rubber, refrigerator type that are barely magnetic. I can't imagine they will mess up this equipment unless they are pretty close to it. I assume the vault itself has restricted access.

One of my friends used to sell magnets for health. She claimed that she cured people with them and truly believed in them. They cost a lot of bucks too and were pretty worthless magnets. It is amazing how easy it is to fool otherwise intelligent people with a little techno-babble.

Rick

The education and common sense level of those that apply for jobs these days are amazingly low. But we need to have business as usual.

There is generally no problem with those that operate the equipment, it's those that aren't usually in that area, like material handers, brain dead salary, people on tour and the general no nothing grease monkeys and contractors.

The best one's are the truck drivers when they drop a load or back straight into a vault wall. Cracks in the containment walls are not generally a good thing.

Jamie

n the

as

Read up on the placebo effect.

Oh, the irony!

No nothing not never nohow.

Relatively benign quackery, like homeopathy, in that it does nothing at all.

How does a no nothing become a general?

You have to understand how homeopathy works:-

Best regards, Spehro Pefhany

There are many ways to carry out a beam scanning function, so this isn't really a good way to describe the nature of the victim equipment. Is it microwave radar, laser, atomic particle - what type of beam technology is being disturbed?

The different units may be independant, but they will still share power and probably communications. If they are directed at the same target, this is also a common factor. If they run on the same software/firmware revision, in the same time zone, that's also a commonality. The longer-term effects suggest SW that is not particularly error tolerant.

If the 'flux differential array sensors' that went screwy at the same time were indeed multiple and independent of the misbehaving equipment, then it might mean something. If they're just parts of the misbehaving equipment, their output is meaningless.

RL

Do you know why some golfers wore Copper bracelets decades ago?

To make themselves "attractive"?

n the

as

now for the 'non-scientific' answer.

ANY device that constantly reminds the wearer will have a positive effect.

so magent, copper, woven seaweed, doesn't matter what it's made of. Just the fact that the wearer is constantly reminded will produce positive 'anecdotal' information.

IMHO the best diagnostic avenue is a makeshift "magnetic pulse catcher". Could be made with a scope that triggers upon exceeding a prescribed good-bad band. The Instek GDS-series has that, at least my GDS-2204 does. In this case meaning it'll trigger when the normally flat horizontal line wiggles either way. Hang a loop with burden resistor onto it and wait until the next event. There would be a recording afterwards. The shape of the pulse should give some good pointers of what it could be. For example, if you see a brief burst of 60Hz cycles you'd know :-)

Just a thought, in case you guys haven't purged the facility of larger CRT monitors: Those have degaussing coils. Some come on every time their power is cycled, others come on at random. Fridge de-icing loops can also cause some grief because sometimes they consist of a somewhat resistive wire run around its door frame, meaning a loop many feet in diameter.

You enjoy talking in riddles it seems.

Difficult to comment sensibly without knowing what sensor technology you are using and whether or not active shielding is involved.

One possibility is that one of your machines is going haywire and taking the rest down. Or you are being affected by externally sourced radio frequency interference that is wrecking the beam steering.

I presume the application is electron beam lithography but it would make it a lot easier if you clarified this. Synchrotron radiation sources also use electron beams as a means to an end.

Why are you so coy about describing what sort of kit it is?

An academic institution would by now have a simple crude primitive magnetic field disturbance detector knocked up out of fishing line a mirror and a magnet. Laser pointed at the mirror and the whole assembly protected from drafts with a glass tube. Simples.

Sophisticated gear can have complicated modes of failure. At present you have no idea what caused your stuff to go AWOL and the way you are going you will be every bit as mystified the next time it happens too.

If you don't know what an E-Beam is, then I won't bother.

Jamie

Where are you located (part of the world, building occupancy type, etc.)?

Could be geomagnetic, or some guy next door doing some welding.

We have inductive loops attached to the walls, spaced closely to form an array. These loops are all driving via Atmega processors to generate a pulse and fast compactors attached to the inputs.

They daisy chain together and the end unit will connect via serial to the PC.

The program in each does not generate its own ID however, the values for each zone are appended to a packet and the size of the packet and CRC are recalculated. We have an input assigned to the uC indicating it is the first unit via jumper, so it'll start TXing immediately and the others will wait for a packet to arrive and then send it to the next, etc.

The first unit will pause sending for the maximum time it would take all 16 devices to send if they were implemented or if some error resulted in the link some how.

With this kind of configuration, you are able to see moving objects as they pass by the wall.

We don't use a BFO method because it is far to unstable but found that using time constant on L works very well. The mosfet switches are used to energize the coils. THe gate is driven via a bjt from the uC for the on state and for the off state a pull down R is present at the gate to allow for a slow turn off, we did this to avoid the wheeling voltages and not use diodes, so far it seems to work

I use the atmega due to high IO count, so each uC can accumulate many zones which will keep the lag down.

Also to add to that, when sampling in the group of IO's we need to stagger loops, meaning, we can't energize a loop adjacent for obvious reasons.

There are other little details we do with this system but I won't get into that. Jamie

The E-beam processing is far from any form of known electrical disturbance and it's housed in its own building attached to the main structure..

Long before I was there, it was required it had to be built on a cement slab to insure nothing below it was there. In the main building we have transformer vaults but nothing goes under this building for the E-Beam. Also it had something to do with environmental laws.

We are located in the center of CT, Northeast US.. I know Maine just recently had an earth quake but as for as I know, we had no issues with that here. Actually, the only think that happen was my dog getting scared of something at the time it happen and insisted she had to come in. I let her in and I noticed her tail was between her legs, she was afraid of something, I had no idea what it was at the time.

There was reports of ground shakes, I didn't feel anything myself, most likely too wrapped up with other things :0

Jamie

It's not benign when it sucks money out of people's pockets. She loaned me a six inch square pad to try on my back, she *insisted* in fact, and when it didn't work she really wanted it back as it cost $100!

More recently she moved to the Sedona, AZ area and I don't see much of her. She may be a wacko, but I might visit her some day.

Rick