After posting I realized that a ferrite 'bead' is just like a one turn toroid. So it is pretty hard to couple in any field. It might be fun to try and measure. A one loop 'pick-up' coil versus a coil with a ferrite bead on it.
George H.
After posting I realized that a ferrite 'bead' is just like a one turn toroid. So it is pretty hard to couple in any field. It might be fun to try and measure. A one loop 'pick-up' coil versus a coil with a ferrite bead on it.
George H.
Loops in the PCB trace layout will be better magnetic pickups than a ferrite bead.
Thats way too expensive for such an old scope. I strongly doubt you can actually use this scope at 3GHz. It has BNC inputs (where most other equipment uses N or SMB for anything over 500MHz). There several offered on Ebay but they are not getting sold for 5k.
John Larkin a écrit :
And the comments above the wonderful circuit is pretty bad as well...
(a) You can buy four of them for the price of anything comparable new; (b) They work great. (c) Nobody spending his own money buys for what the dealers are asking.
I've got one on my shopping list for 2012--we'll see!
Cheers
Phil Hobbs
BNCs work fine at 3 GHz. But you'd need active probes in a lot of situations, like snooping serial busses, and they can get expensive.
Especially if there are unrelated pieces of ferrite sitting inside the loop, yelling "All you fluxes, come here, here is a well-paved road".
A surface-mount ferrite bead is not much magnetic volume. I don't know how they are constructed, but I don't think they are coils... maybe just serpentines. Beads typically have a few uH of base indictance.
This claims that beads are "closed magnetic circuits" and "inherently shielded."
Yeah, could you please translate that into English for us?
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