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Date
Re: eBay buyer protections are poor
This is excellent packing advice, and this is exactly why stuff like new TVs are also packed this way: engineers have researched the issue and come up with this stuff, since a lot of big things like
By Daniel Wolstenholme · #73738 ·
Re: Why is Mu Metal used?
Mu metal is a shield for magnetic fields. It has extremely high permeability, the ability to conduct magnetic fields the Greek letter Mu u is the symbol for permeability. See:
By Richard Knoppow · #73737 ·
Re: [TekScopes] Re: Why is Mu Metal used?
Ahh ok, now THAT makes sense and tells me a lot + gives me some keywords to follow up on. Thank you very much! <hp_agilent_equipment@...> wrote:
By cheater cheater · #73736 ·
Re: [TekScopes] Re: Why is Mu Metal used?
The skin depth for copper at 60 Hz is large enough that significant field energy can penetrate through material thin enough to be practical, resulting in interference. Mu metal (iron that has been
By Jeff Kruth · #73735 ·
Re: eBay buyer protections are poor
I disagree. I have bought Agilent ESG-DP, 8341B, 8753ES, 4395A, E4440A, Tek CSA8000, R+S misc, and various heavier advantest equipment in the past year or so. The key is to use the 3" semi-hard foam
By twrch@... · #73734 ·
Re: [TekScopes] Re: Why is Mu Metal used?
Another reason, the CRT beam is most?susceptible to magnetic fields as seen in the television deflection yoke scanning the beam. A sufficient magnetic field close to the CRT will deflect or modulate
By Jack Mcmullen <forjack842@...> · #73733 ·
Re: [TekScopes] Re: Why is Mu Metal used?
Hello-- ...And Mew Metal shielding will keep cats out of transmitters....<g>. 73-- Brad AA1IP
By Brad Thompson · #73732 ·
Re: [TekScopes] Re: Why is Mu Metal used?
I know they're different Jack, I'm asking how. Cheers [hp_agilent_equipment] <hp_agilent_equipment@...> wrote:
By cheater cheater · #73731 ·
Re: [TekScopes] Re: Why is Mu Metal used?
You're comparing apples and oranges. 60hz Magnetic fields are what MU-metal are best at filtering out. Copper screen is best for shielding RF electric fields as radiated from antennae. Jack KG6INX
By Jack Mcmullen <forjack842@...> · #73730 ·
Re: [TekScopes] Re: Why is Mu Metal used?
I understand a changing magnetic field would induce a current in the copper foil, and so the magnetic field would effectively be "used up" by the copper foil, though. Why is copper shielding not
By cheater cheater · #73729 ·
Re: Why is Mu Metal used?
Hi, Mu metal is used because the shielding is from magnetic fields not electric fields. Copper is diamagnetic so not a good shield of magnetic fields that would deflect the electron beam.
By Robert G8RPI · #73728 ·
Re: Why is Mu Metal used?
The Mu-Metal exhibits ?a shield against 60hz transformer magnetic fields commonly known to induce beam distortion.
By Jack Mcmullen <forjack842@...> · #73727 ·
Why is Mu Metal used?
Hi guys, Why is Mu Metal used to shield CRTs in scopes, rather than just grounded copper foil? I never understood the precise reason for that. Thanks
By cheater cheater · #73726 ·
Hp 70900B ROMs
Hi everyone, I am posting this here in hopes that someone out there can help me with a MAJOR mistake! I erased the EEPROM to my HP70900B Local Oscillator, this in turns kills using the Spectrum
By amgod@... · #73725 ·
Re: eBay buyer protections are poor
In the past I've very successfully shipped test equipment. Unfortunately, to pack it right takes strong boxes and good packing materials and these aren't always available for free. The extra size and
By Peter Gottlieb · #73724 ·
Re: eBay buyer protections are poor
Sellers frequently give no choice, they ship how they want to ship and you pay the cost. The pricing formulas are different at USPS, UPS and FedEx which means that for any particular package,
By Peter Gottlieb · #73723 ·
Re: eBay buyer protections are poor
So out of a country of 310 million people, you managed to find a few people who have no clue how to pack stuff. Big surprise. That's what you get for buying from people who aren't professional packers
By Daniel Wolstenholme · #73722 ·
Re: eBay buyer protections are poor
You can get 100 resistors for cheaper than that from Digi-Key; why would you buy junky no-name Chinese resistors and wait a month for that price? That's what you get for shipping heavy items via USPS.
By Daniel Wolstenholme · #73721 ·
Re: eBay buyer protections are poor
I think you are being a bit unfair on a lot of Chinese sellers who are pretty honest and safe to deal with. I have bought hundreds of items from China and I would say well over 90 percent of them were
By Peter VK2AN · #73720 ·
Anyone know how to get an HP 83623A 20 GHz sweeper to step in 1 Hz?
The default stepsize of the 83623A 20 GHz sweeper is 1 kHz. HP in their attempt to extract as much money as possible, made the 1 Hz steps a software option (008). Does anyone know to add option 008 to
By Dr. David Kirkby (Kirkby Microwave Ltd) <drkirkby@...> · #73719 ·